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Evaluation of outcomes for cardiac arrest patients treated by Provincial Ambulance Service personnel… Wilson, Lynn E. 1982

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EVALUATION OF OUTCOMES FOR CARDIAC ARREST PATIENTS TREATED BY PROVINCIAL AMBULANCE SERVICE PERSONNEL IN THE LOWER MAINLAND OF BRITISH COLUMBIA by LYNN E. WILSON B.A., Concordia University, 1968 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE FACULTY OF GRADUATE STUDIES DEPARTMENT OF HEALTH CARE £ EPIDEMIOLOGY HEALTH SERVICES PLANNING PROGRAM We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA September 1982 Lynn E. Wilson, 1982 In presenting this thesis in partial fulfilment of the requirements f an advanced degree at the University of British Columbia, I agree tha the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the Head of my Department or by his representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of Health Care & Epidemiology The University of British Columbia 2075 Wesbrook Place Vancouver, Canada V6T 1W5 August 2 8 , 1982 i i ABSTRACT Information was collected in an eight and a half month prospective study about 358 recent cardiac disease-related cardiac arrest cases which were attended by personnel from the Provincial Ambulance Service in the Lower Mainland of British Columbia. When possible, advanced life support personnel (EMA Ills), regular ambulance attendants (EMA Ms) and Fire Department staff are dis-patched to cardiac arrest calls. At the time of this study some areas in the region did not have advanced life support coverage, and some cardiac arrest calls occurred while the EMA Ills were already engaged with another case. Such calls, attended by EMA lis, but not by EMA Ills, served as the comparison group for paramedic performance in this study. Patient outcomes were compared at admis-sion to hospital and at discharge from hospital for the group of patients treated by EMA Ms and the group of patients treated by EMA Ills, or by a combination of EMA Ills and EMA Ms. Strongly significant differences in initial outcome (hospital admis-sion) were found between the two patient groups, with EMA IM patients faring better (p.=0.002). Marginally significant differences in final outcome (discharge alive) between the two patient groups were found, with the EMA III group again doing better (p.=0.10). Whether or not the receiving hospital had a coronary care unit was not as-sociated with a difference in initial (p.=0.45) or final outcome (p.=1.0) for the entire group of patients in the study. Short time in arrest without CPR was associated with better initial outcome (p.=0.00), and with better final outcome (p.=0.01) for all patients i i i in the study, as was short time to definitive care (initial outcome p.=0.001; final outcome p.=0.03). EMA II patients had a better chance of survival when they arrested during attendance by EMA lis than they did when they were found in arrest. This study suggests that significantly more cardiac arrest victims reach hospital alive, and more survive to be discharged alive from hospital, when their prehospital treatment is provided by advanced life support personnel than when it is provided by regular ambulance personnel. TABLE OF CONTENTS PAGE ABSTRACT i i LIST OF TABLES ii LIST OF FIGURES Ix ACKNOWLEDGEMENT . j< CHAPTER I INTRODUCTION 1 PREHOSPITAL CORONARY CARE IN BRITISH COLUMBIA 2 RESEARCH QUESTIONS k DEFINITIONS 5 THE RESEARCH STUDY 6 CHAPTER II LITERATURE REVIEW 7 EVALUATION STUDIES 7 ADVANCES IN CARDIAC CARE CRITICISMS OF PREHOSPITAL CORONARY CARE PROGRAMS EVALUATION STUDIES OF PREHOSPITAL CORONARY CARE STUDIES OF OUTCOMES FOR CARDIAC ARREST VICTIMS TREATED BY PARAMEDICS 22 OTHER LITERATURE 31 CHAPTER III DEVELOPMENT OF THE ADVANCED LIFE SUPPORT PROGRAM IN B.C. 32 CHAPTER IV STUDY METHODOLOGY 39 DISPATCH SYSTEM hk HANDLING OF CARDIAC CALLS STUDENT CLERKSHIP hi INITIATION OF THE PROJECT *»8 V PAGE PROBLEMS WITH DATA COLLECTION 52 VARIABLES INCLUDED IN THE STUDY 5^ IN-HOSPITAL COURSE 55 DATA PREPARATION 56 RELIABILITY AND VALIDITY ISSUES 56 - Reliabili ty 56 - Validity 56 - External Validity, or Generalizabi1ity 59 CRITERIA FOR SIGNIFICANT DIFFERENCE IN STUDY FINDINGS 60 CHAPTER V FINDINGS 62 RESULTS 62 - Cardiopulmonary Resuscitation 66 - Time In Arrest Wi.thput CPR 67 - Receiving Hospital 69 - Time To Definitive Care 70 ^ Length, of Hospita 1 tzatton 71 - Survivors 72 CHAPTER VI DISCUSSION AND CONCLUSIONS 7k RESEARCH QUESTION 1 7k RESEARCH QUESTION 2 78 OTHER VARIABLES EXAMINED 80 - Time In Arrest Without CPR 80 - Time To Definitive Care 81 - Witnessed Arrests 83 - Course While In Hospital For Those Admitted Alive 8k - Length of Hospitalization 85 CONCLUSIONS AND EVALUATION OF THE STUDY 85 DIRECTIONS FOR FUTURE RESEARCH 87 v i PAGE BIBLIOGRAPHY 90 APPENDIX A PART 1: DEFINITION OF ADVANCED LIFE SUPPORT 104 PART 2: ESTIMATED COST IN 198l-1982 DOLLARS OF OPERATING A SINGLE EHS VEHICLE FOR ONE YEAR 104 APPENDIX B CREW REPORT 106 APPENDIX C PART 1: STUDY DATA COLLECTION FORM 107 PART 2: STUDY DATA ANALYSIS FORM 108 APPENDIX D CERTIFICATE OF APPROVAL FOR RESEARCH INVOLVING HUMAN SUBJECTS 109 APPENDIX E ADDITIONAL ANALYSES: TABLES E 1 THROUGH E 12 110 BIOGRAPHICAL FORM 117 V I I LIST OF TABLES PAGE TABLE I TABLE I I NUMBER AND PERCENTAGE DISTRIBUTION OF OUTCOMES FOR STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT 6k NUMBER AND PERCENTAGE DISTRIBUTION OF PATIENTS FOUND IN ARREST AND ARRESTING DURING ATTENDANCE BY TYPE OF RESPONDING ATTENDANT 65 TABLE III NUMBER AND PERCENTAGE DISTRIBUTION OF PATIENTS WHO WERE AND WERE NOT RECEIVING CPR ON ARRIVAL OF EMAs BY TYPE OF RESPONDING ATTENDANT TABLE IV NUMBER AND PERCENTAGE DISTRIBUTION OF FOUND IN ARREST PATIENTS WHO RECEIVED OR DID NOT RECEIVE BYSTANDER CPR BY TYPE OF RESPONDING ATTENDANT TABLE V MEDIAN TIME IN ARREST WITHOUT CPR FOR STUDY PATIENTS BY OUTCOME TABLE VI MEDIAN TIME IN ARREST WITHOUT CPR FOR STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT TABLE VII NUMBER AND PERCENTAGE DISTRIBUTION OF PATIENTS RECEIVED BY HOSPITALS WITH AND WITHOUT CORONARY CARE UNITS BY TYPE OF RESPONDING ATTENDANT TABLE VIII MEDIAN TIME TO DEFINITIVE CARE FOR STUDY PATIENTS BY OUTCOME 66 67 68 69 70 71 APPENDIX E - TABLE I NUMBER AND PERCENTAGE DISTRIBUTION OF AGES OF STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT 110 v i i i APPENDIX E continued PAGE TABLE I I - TABLE I II TABLE IV TABLE V TABLE VI TABLE VI I TABLE VIII TABLE IX TABLE X TABLE XI TABLE Xll NUMBER AND PERCENTAGE DISTRIBUTION OF SEX OF STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT HO NUMBER AND PERCENTAGE DISTRIBUTION BY TIME OF DAY OF INCIDENT FOR STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT 110 NUMBER AND PERCENTAGE DISTRIBUTION OF OUTCOMES FOR STUDY PATIENTS FOUND IN ARREST BY TYPE OF RESPONDING ATTENDANT 111 NUMBER AND PERCENTAGE DISTRIBUTION OF OUTCOMES FOR STUDY PATIENTS ARRESTING DURING ATTENDANCE BY TYPE OF RESPONDING ATTENDANT 112 TIME IN ARREST WITHOUT CPR BY TYPE OF RESPONDING ATTENDANT: MEAN TIME/MEAN TIME FOR LOG-TRANSFORMED DATA AND t-TEST ON LOG-TRANSFORMED DATA MEANS 113 MEAN TIMES AND SKEW FOR TIME IN ARREST WITHOUT CPR BY TYPE OF RESPONDING ATTENDANT FOR ORIGINAL AND LOG-TRANSFORMED DATA 113 NUMBER AND PERCENTAGE DISTRIBUTION OF OUTCOMES FOR STUDY PATIENTS RECEIVED BY HOSPITALS WITH AND WITHOUT CORONARY CARE UNITS 114 MEDIAN TIME TO DEFINITIVE CARE FOR STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT 115 MEDIAN LENGTH OF HOSPITALIZATION FOR STUDY PATIENTS DISCHARGED ALIVE BY TYPE OF RESPONDING ATTENDANT 115 MEDIAN LENGTH OF HOSPITALIZATION FOR STUDY PATIENTS WHO DIED IN HOSPITAL BY TYPE OF RESPONDING ATTENDANT 116 MEDIAN LENGTH OF HOSPITALIZATION FOR STUDY PATIENTS WHO DIED IN HOSPITAL COMPARED TO STUDY PATIENTS WHO WERE DISCHARGED ALIVE 116 ix LIST OF FIGURES PAGE FIGURE I GEOGRAPHICAL AREAS WITH AND WITHOUT ADVANCED LIFE SUPPORT VEHICLE COVERAGE IN THE LOWER MAINLAND OF BRITISH COLUMBIA X ACKNOWLEDGEMENT This study would not haye been possible without the support of many groups and individuals. I am very grateful to Health and Welfare Canada, which provided -me with a student fellowship for two years of my studies, and to the Emergency Health Services Commission of British Columbia, which opened its records to me and made a summer clerkship possible. Thanks are due also to the Royal Columbian/Douglas College Joint Education Venture which provided some funding and clerical support for the project. I want to thank Dr. Les Vertesi, Medical Director of the Advanced Life Support Program, who spent a great deal of time with me discussing the project and designing study data collection forms. He smoothed the way with people both inside and outside the organi-zation whose support was essential to the project. It was invalu-able to have union support for the study, and I am particularly grateful to all the EMA Ms who completed the study form in addition to their regular paperwork. I am sure that it was not always convenient for them to do this. I would like also to express my gratitude to my thesis committee. Dr. Annette Stark, Chairman, was singularly patient as the project proceeded in fits and starts. She encouraged me to carry on when I was discouraged by the problems of doing research in the "real world". Dr. Ned Glick, who acted as statistician, reminded me of how to organize my thoughts and findings for presentation so that they could be more easily understood. Dr. Don Studney was kind x i enough to become a committee member toward the end of the analysis, and his comments from the perspective of an academic physician were most helpful. Anne Wilson proof-read, drew maps, and generally provided moral support while this document was being prepared. Lastly, (but certainly not least), f would like to express my sincerest appreciation to Ronnie Sizto for all his help with in-numerable computer runs to analyze the study data. Were it not for him, I am sure I'd still be at it! 1. CHAPTER I  INTRODUCTION This study was designed to assess the impact of the advanced life support program of the Provincial Ambulance Service in British Columbia on outcomes for patients with cardiac arrests treated by the ambulance service. Much has been written over many years about the magnitude of the problem of heart disease, not only in North America, but in many of the developed countries of the world. In spite of recent advances in treatment and an observed decreasing trend in mortality rates for ischemic heart disease and acute myocardial infarction, over 6 5 0 , 0 0 0 deaths annually are still attributable to coronary heart disease in the United States alone (Bergner, Eisenberg, Hallstrom & Becker, 1 9 8 1 ; Rosenberg & Klebba, 1 9 7 9 ) . In Canada in 1978, the most recent year for which such statistics are available, over 5 5 , 0 0 0 people died from cardiac disease (Statistics Canada, 1 9 8 0 ) . This represents about one-third of deaths from all causes for that year, and indicates that the problem is still an important one. Many of those dying are individuals with many potentially productive years, whose contribution has been interrupted by pre-mature death. The economic cost of these deaths is substantial. One estimate suggests losses are from 38 to 57 billion dollars a year (Bergner et al., I 9 8 I ) . Because of the continued magnitude of the problem of heart disease, a great deal of effort and many research dollars have been 2. spent on studying its prevention and treatment. The result has been a number of advances in cardiac care within hospitals in recent years, from special coronary care units, which became widespread during the 196O1s, to new drugs, to coronary bypass surgery for selected patients. However, because the majority of cardiac deaths occur soon after an attack (as many as two-thirds die within the first k hours of onset of a myocardial infarction, for example), intervention during the initial stages of an acute event is essen-tial. It is generally accepted that without prompt, appropriate, intervention, patients experiencing a cardiac arrest will die. In order to save lives, then, advanced cardiac care must reach these victims in the community, before they are hospitalized. Usually this becomes the responsibility of the group providing emergency medical services for the community. In British Columbia this is the Provincial Ambulance Service of the Emergency Health Services Commi ssion. PREHOSPITAL CORONARY CARE IN BRITISH COLUMBIA Ever since Pantridge and Geddes C1967) reported success with mobile coronary care units in Belfast, programs have proliferated throughout the United States, generally in large metropolitan areas. Currently there are at least three hundred paramedic programs (Eisenberg, Bergner, & Hallstrom, 1980a), one of the most well-publicized and apparently successful of which was established in Seattle (Bergner et al., 1981 ; Hoffer, 1979). 3. In 1974 the Emergency Health Services Act was passed in British Columbia (British Columbia, 1974). It provided for estab-lishment of a provincial ambulance service to serve citizens throughout the province. Ambulance personnel, by the very nature of their activities, came into regular contact with emergency depart-ment staff at local hospitals who encouraged them and helped them to improve their emergency treatment skills. Eventually, emergency physicians working in the hospitals expressed a willingness to train ambulance personnel to undertake advanced life support for cardiac patients in order that these patients would arrive at the emergency department in better condition. This movement was given further momentum by the publication of very encouraging results from the Washington State programs, particularly since Vancouver and the Lower Mainland area generally, were perceived to be very similar to Seattle and its suburbs where the paramedic programs had been established. By the end of 1974 most of the legal hurdles for establishing a paramedic program had been dealt with, and the first team of trained paramedics had been approved. Working out of Royal Columbian Hospital in New Westminster, British Columbia, paramedics began accepting emergency calls in April 1975 (verbal communication: Dr. L. Vertesi, currently Medical Director of the Advanced Life Support Program). This pilot project was strongly supported by the medical com-munity in the area, and in time additional paramedic vehicles were equipped and staffed to work out of other ambulance stations in d i f f e r e n t parts of the Lower Mainland. Service personnel were convinced that the advanced l i f e support vehicles and personnel were a valuable addition to the emergency services of any community, and there was pressure for further expansion of the program, which continues even today. In the face of this pressure, an i n i t i a l evaluation of the impact of the paramedic program was proposed. RESEARCH QUESTIONS This study was designed to evaluate outcomes for recent cardiac arrest victims in the Lower Mainland of B r i t i s h Columbia who were treated by one or more types of Provincial Ambulance Service personnel before they were taken to h o s p i t a l . This rather limited group of patients was chosen for evaluation because outcomes for people with this condition were unambiguous (alive/dead), other s i m i l a r programs were reporting t h e i r success with these cases, and because cardiac care was expected to be a major component of the a c t i v i t i e s of the paramedics: i t was expected that as many as 70 per cent of the c a l l s to which the paramedic vehicles would be sent would be from patients with cardiac problems (verbal communication: L. V e r t e s i ) . The research questions were: 1. Are there s t a t i s t i c a l l y s i g n i f i c a n t differences in the proportion of patients surviving to hospital admission between the group of patients treated by Emergency Medical Assistant M s only (EMA M s — regular ambulance personnel) and those treated by Emergency Medical Assistant I l l s only (EMA I I Is--paramedics/advanced l i f e support personnel) or a combination of EMA I l l s and EMA M s ? 5. 2. Are there statistically significant differences in the proportions of patients discharged alive from hospital between the group treated by EMA Its only and the group treated by EMA Ills only or a combina-tion of Ills and I Is? DEFINITIONS: Cardiac arrest: for purposes of this study, a patient with a cardiac arrest was a patient with an apparently pulseless condition confirmed by ambulance personnel (see p. 63 for information about excluded cardiac arrest cases). EMA I I: an ambulance attendant who has been trained in and has passed examinations for providing advanced level first aid. EMA III: an ambulance attendant trained in and successfully examined for providing advanced life support, as defined by the American Heart Association (for definition refer to Appendix A, Part 1). This type of personnel is also known as paramedics and as advanced life support personnel. Bystander CPR: cardiopulmonary resuscitation undertaken by any individual who is not a member of the ambulance service and is not employed by either the Police or the Fire Department. Time Without CPR: generally this is an estimate in minutes made by the ambulance crew member completing the study form of the interval from when the patient seemed to stop breathing to the time when someone started CPR, based on discussions with people at the scene or on personal observation. Where the collapse was not witnessed, this information is not 6. ' available. Time To Definitive Care: for EMA Tl cases, this was deemed to be the time from receipt of the call at central dispatch until the time when the patient arrived at the hospital. For EMA 111 cases, this was deemed to be the time from receipt of the call at central dispatch, until the time when the EMA III crew arrived at the scene of the incident. THE RESEARCH STUDY This first chapter has provided a very general introduction to the evaluation project. Chapter II presents a review of literature on evaluation, coronary care, mobile coronary care, and the evaluation of mobile coronary care. Chapter III describes how the advanced life support program was established in British Columbia. Chapter IV describes in detail the methodology for the study, discusses reliability and validity issues, and outlines the analytic techniques employed for the analysis of findings. Chapter V presents the findings from the study, which are discussed at length in Chapter VI. Chapter VI also deals with implications for planning and suggestions for further research in the area. CHAPTER I I 7. LITERATURE REVIEW EVALUATION STUDIES Why evaluate? What is the purpose of evaluation projects? Weiss 0972) suggests that the purpose of evaluation is "to measure the effects of a program against the goals it set out to accomplish as a means of contributing to subsequent decision making about the program and improving future programming" (p. h). In the field of health care, evaluations are important. Many authors have discussed the fact that expenditures for health care are very large in absolute terms, and the size of these expenditures, often from the public purse, has grown rapidly (Barstow, 1982; Evans, 1975; Shortell & Richardson, 1978; Thorner, 1979; Winkelstein, 1972). Particularly in difficult economic times such as those we now face, governments want to know that their scarce resources are being used well, and evaluation provides some information on this subject. If a program is falling far short of its goals, governments may want to consider whether or not support for the program should continue. Of course, information provided by a program evaluation project has to be considered in light of other important factors such as whether or not there are alternative ways to achieve the goals, and whether or not the program is cost-effective compared to possible alternatives (Hoffer, 1979; Shortell & Richardson, 1978; Sidel, Acton, & Lown; 1969; Suchman, 1967; Weiss, 1972). Although it is reasonable to 8. evaluate programs, results from evaluation studies are not absolute; that is, they do not often provide decision-makers with information which is so hard and fast that decisions can be made about whether or not the program should continue (Cain £ Hollister, 1972). Results have to be looked at together with other factors which have an impact on the program (Rossi 6 Williams, 1972). Acknowledgment of this is important, because evaluators must depend on the cooperation of those running the program which is to be evaluated. If trust is not es-tablished between the parties participating in such studies, there are many ways in which the project can be sabotaged. It is acknow-ledged that evaluation takes place in a political setting: The interest is in finding positive effects and not negative effects or no effects at all. Those who have proposed programs do so with the conviction that the programs are effective; those who administer the programs have an interest in showing that under their leadership the programs have accomplished something; and evaluators who are connected more or less intimate-ly with the programs are not likely to want to offend by showing that programs do not work. (Rossi & Williams, 1972, p. 22) There are a number of ways to look at evaluation. Schulberg Sheldon and Baker (1969) suggest two basic models - goal achievement and systems. They indicate that the former is a more limited way to approach evaluation, and the latter is more difficult. The systems model contends that organizations always have a variety of objectives, and success in achieving any one goal must be studied in light of the impact that this has on other organizational goals. Evaluation can be designed primarily to provide feedback for 9 . program improvement as the evaluation is carried out, or it can be primarily for assessment of degree of success in achieving speci-fied outcomes. In the first case the evaluation report is directed primarily to service providers and administrators; in the second, to policy makers, either within or outside the organization. The report has to be tailored to the audience for which it is intended (Rossi & Wright, 1 9 7 7 ) . Evaluations which serve as aids to planning are concerned with relating resource inputs to outcomes. Studies which describe pro-grams in terms of their resources are often the simplest studies. Studies looking at the processes which take place within the program as service is provided are somewhat more difficult. The type of study which is generally most difficult and costly to do well is the outcome evaluation study. Outcome, however, is of critical importance. A major problem in conducting such studies is determina tion of valid and useful measures of output or outcome, particularly since outcomes themselves might be quite different, depending on the perspective used (Willemain, 1977)• Successful outcomes for a program may be quite differently defined by patients, clinicians, patients' families, training institutions, consumer advocates, and funding agencies (Attkisson & Hargreaves, 1 9 7 9 ) . An evaluation study, then, ideally starts with a statement indicating the perspective from which it is being undertaken. It proceeds to a statement about the goals, in clear, specific, achievable, measurable terms, which have been agreed to for the 10. program being evaluated. Once goals have been identified, then criteria to be used to measure the success of the program in achiev-ing these goals must be identified and agreed to by all parties participating in the evaluation. Once there is consensus on these issues, then measurements of program performance can be undertaken. Hopefully these measures will permit assessment of the degree of success the program is having in achieving its stated objectives, and determination of whether or not successful outcomes can reason-ably be attributed to program activities (Ibrahim, 1976; Rossi & Williams, 1972; Schulberg et al., I969). ADVANCES IN CARDIAC CARE A number of major developments in the treatment of myocardial infarction patients have occurred since the early 196O1s. Two important advances were introduction of coronary care units in hospitals and coronary bypass surgery for selected cardiac patients. While these developments met with enthusiastic approval when they were first introduced, the initial favorable evaluation has since given way to concern about the benefits to be derived from their widespread use (coronary care units: Colling, Dellipiani, Donaldson, & MacCormack, 1976; Hill, Holdstock, & Hampton, 1977; Lown £ Selzer, 1968; Mather, Morgan, £ Pearson, 1976; Peterson, 1976), (coronary bypass surgery: Aronow £ Stemmer, 1975; Braunwald, 1977; Hutter, Russell, Resnekov, et a., 1977; Murphy, Hultgren, Detre, et al., 1977). 11. Regardless of whether these developments in care help or hinder patients, patients must reach the hospital alive if they are to benefit from them. Numerous studies have indicated that from half to two-thirds of those experiencing heart attacks die before reach-ing hospital care, many within the first hours after the onset of symptoms (Acton, 1973; Mclntyre, 1979; Pantridge & Geddes, 1967; Pyo & Watts, 1970, Sidel et al., 1969; Tweed £ Wilson, 1977)-Canadian statistics for 1978, the most recent year for which data are available, indicate that a total of 55,362 Canadians died of heart disease. The figure for British Columbia is 6,001 (Statistics Canada, 1980). When we consider that the attack rate is several times the death rate (Nagel, Hirschman, Nussenfeld, & Rankin, 1970), we can see that in terms of numbers alone, this is a signifi-cant health problem. In recent years the rates of coronary heart disease mortality have tended to decrease in North America and some other, though not all other, developed countries. A variety of hypotheses have been advanced to explain this observation: changes in lifestyle which have reduced risk, treatment changes such as the development of coronary care units and availability of new drugs (e.g., those to control rhythm disturbances), changes in surgical practice (e.g., coronary bypass surgery), and emergency system changes (e.g., better emergency communication systems, and more people trained in lay CPR techniques) (Cooper, Stamler, Dyer,, £ Garside, 1978; Editorial, The Lancet, 1980; Eisenberg, Bergner, £ Hallstrom, 1980a; c Rosenberg £ Klebba, 1979; Stallones, 1980; Stern, 1981). Probably 12. the observed decline is attributable, at least in part, to each of these factors, although the magnitude of the contribution of certain of the factors is still a matter of debate, as suggested earlier. If further reductions in mortality rates from heart disease are to occur, the attack on this complex of problems will have to con-tinue to be multi-faceted. Although the largest gains will likely be from activities such as screening and prevention, prehospital coronary care will remain important because "Better than half, per-haps better than 65% of those who die suddenly, prematurely, and unexpectedly do so in the kitchens, churches and shopping centres of their communities..." (Mclntyre, 1979 , P- 8 9 ) . Thus, effective prehospital coronary care can contribute to a continued decline (Crampton, Aldrich, StiHerman, et al., 1975b; KM lip, 1979 ; Myerburg, 1979; Nagel , 1979; Sidel et al., 1 9 6 9 ) . Provision of advanced life support via mobile units within the community is a response to the following observations: - Sudden death is frequently due to a disturbance in heart rhythm, generally ventricular fibrillation, which if untreated leads to asystole (Cobb, Baum, Alvarez, & Schaffer, 1975 ; Moss, Wynar, & Goldstein, 1969; Pantridge & Adgey, 1969 ; Sidel et al., 1 9 6 9 ) . - Arrhythmia death is frequently preventable and reversible (Pantridge & Geddes, 1967 ; Sidel et al., 1969 ; Wallace 6 Yu, 1975) provided that the patient receives appropriate treatment soon after onset of the attack. 13-- Because rhythm problems frequently develop or increase during transport, possibly as a result of moving the patient (Crampton, Aldrich, Gascho, Miles S StiHerman, 1975a; Pantridge & Adgey, 1969; Pantridge 5 Geddes, 1967), it is important to stabilize the patient's condition at the scene and to have personnel who are able to deal with problems which might develop en route accompany the patient to the hospital. Advanced life.support units worthy of that designation, in addition to basic life support capability, have special equipment and techniques available: effective emergency communications systems, appropriate drugs, cardiac monitors, defibrillators, equipment for endotracheal intubation and establishing and maintain-ing intravenous infusion lifelines (Standards for Cardiopulmonary Resuscitation, 197*0. The prototype mobile coronary care unit was developed in 1966 in Belfast (Pantridge & Geddes, 1967), and was staffed by physicians. This type of staffing proved impractical in North America, and the mobile prehospital coronary care units which were developed in areas such as Seattle, Miami, and Los Angeles County, were manned by para-medics specially trained to deal with cardiac emergencies (Cobb, Alvarez, & Copass, 1976; Lewis £ Criley, 1977; Liberthson, Nagel, Hirschman, 6 Nussenfeld, 197*0. These advanced life support pro-grams using paramedics served as the models for the development of a paramedic ambulance service in Vancouver (verbal communication: 14. L. Vertesi, 1 9 7 8 ) . In addition to prevention of deaths from heart attacks, a variety of other benefits accrue from the prehospital coronary care provided by community-based emergency services personnel: reduced incidence of cardiac arrests and shock and pump failure, relief of pain, reduction in the number of cardiac invalids, peace of mind for citizens who know the service is available if it is needed for them-selves or for family and friends, greater awareness among the general public of the symptoms of heart attack and of the importance of call-ing for help quickly, more people in the community willing to make the effort to take CPR training, and more opportunities to prevent heart attacks because of increased awareness and receptivity to public information about the disease (Adgey & Geddes, 1977; Crampton et al., 1975b; Steel, Cooper, & Fox, 1969; Urban, Bergner, & Eisenberg, 1981). Even with unsuccessful outcomes there are potential benefits: family members are comforted by the knowledge that everything that could be done under the circumstances was done for the victim, and if the patient is an organ donor, medical personnel can be made aware quickly that donated organs are available (Outcome Measurement Panel, 1975). CRITICISMS OF PREHOSPITAL CORONARY CARE PROGRAMS Reports in the literature about prehospital coronary care programs have not been uniformly positive. Mclntyre (1979), Pyo and Watts (1970), Schwartz (1974), Shu (1971), Steel, Cooper and Fox, 15 . (1969) have all voiced some concern. One reservation is the high cost of having an advanced life support program (Anderson, Knobel, & Fisch, 1971 ; Schwartz, 197*0. This criticism has been addressed by several authors. It was pointed out that in North America the units are generally manned by paramedics, rather than by teams of doctors and nurses, and this use of auxilliary personnel tends to reduce costs (Graf, Pol in, & Paegal , 1973; Luxton, Peter, Harper, £ Hunt, 1 9 7 5 ) . It is possible to use regular ambulances which have been adapted and supplied with portable equipment, rather than expensive, specially-built and equipped vehicles (Binnion, Mandal, £ Makous, 1973 ; Graf et al., 1975 ; Yu, 1 9 7 1 ) . Finally, as Yu has pointed out, the relatively high cost of implementing some of the systems has been the funding of the research projects which have been associated with them. Some have suggested that advanced life support units do not benefit enough people to make them a worthwhile investment of scarce health care resources (Nagel , Liberthson, Hirschman, £ Nussenfeld, 1975 ; O'Rourke £ Michaelides, 1975 ; Yu, 1 9 7 0 - Graf et al. (1973) noted that an intensive publicity compaign about the program in-creased the volume of emergency calls without increasing the pro-portion of inappropriate calls, so efforts to increase public awareness will enable the program to benefit more people. Even when an advanced life support vehicle responds to an inappropriate call, "Some education of the public is accomplished every time the mobile unit picks up a patient....Education is a most necessary step in the 16. treatment of heart attacks..." (.Bi.nni.on et al., 1973, p. 923). Furthermore, surely some benefit is derived from the service when it is determined that no major problem exists, in terms of peace of mind for the patient (Sidel et al., 1969). In British Columbia the problem of small numbers of people benefiting from the service is minimized, since paramedic ambulances respond to a variety of types of emergency calls. Rapid arrival of help in the initial stages of an incident is essential. Five minutes without attention may be too long for cardiac arrest victims (Aronow, 1981; Copley, Mantle, Rogers, Russell, S Rackley, 1977; Eisenberg, Bergner, & Hallstrom, 1979a). If, as has been shown in several studies, the major component in delay to medical treatment is patient or patient/physician delay in asking for assistance (Cretin & Willemain, 1979 ; Hackett & Cassem, 1969; Mogielnicki, Stevenson, & Willemain, 1977 ; Moss et al., 1969; Pyo & Watts, 1970; Simon, Fienlieb, £ Thompson, 1972), then the opportunity for a paramedic program to have an impact on the course of an emergency may be limited. Public education programs are need-ed to address the issue of patient delay in order to take full ad-vantage of the potential of the service. In the case of sudden collapse, however, provided that the incident is witnessed, delay time is often ambulance response time, and if there are people at the scene capable of initiating CPR and maintaining it until the ambulance arrives, the effectiveness of the paramedic program is enhanced (Cobb et al., 1976; Copley et al., 1977; Eisenberg, 17. B e r g n e r , 6 H a l l s t r o m , 1979c; G u z y , P e a r c e , G r e e n f i e l d , B e c k , & M c E l r o y , 1979; L e w i s £ C r i l e y , 1977; M c l n t y r e , 1979). The i s s u e has been r a i s e d o f w h e t h e r o r no t t h o s e s u r v i v i n g c a r d i a c a r r e s t have s u f f e r e d n e u r o l o g i c d e f i c i t t o s u c h an e x t e n t t h a t t h e y have become a bu rden t o t h e i r f am i1 i es and t o s o c i e t y ( W e b s t e r , 1980). Some r e p o r t s i n d i c a t e t h a t t h i s has no t been a m a j o r p r o b l e m ( L e m i r e £ J o h n s o n , 1975; L e w i s , A i l s h i e , & C r i l e y , 1975; L i b e r t h s o n e t a l . , 1974; P a n t r i d g e & A d g e y , 1969; T r e s c h , G r o v e , K e e l a n e t a l . , 1981), t hough j u s t what c o n s t i t u t e s a s u b -s t a n t i a l p r o b l e m has no t been s t a t e d w i t h any a c c u r a c y , w h i l e o t h e r s t a k e a l e s s o p t i m i s t i c v i e w ( C o p l e y e t a l . , 1977; E a r n e s t , Y a r n e l l , M e r r i l l , £ Knapp , 1980; Lund £ S k u l b e r g , 1976; Tweed , B r i s t o w , £ Donen , I98O). The c a r d i a c p r o b l e m w i t h w h i c h m o b i l e c o r o n a r y c a r e u n i t s have had s p e c t a c u l a r s u c c e s s i s p r i m a r y v e n t r i c u l a r f i b r i l l a t i o n , t h a t i s , v e n t r i c u l a r f i b r i l l a t i o n no t a s s o c i a t e d w i t h m y o c a r d i a l i n f a r c -t i o n . I t i s t h e r e f o r e d i s t u r b i n g t o read r e p o r t s (Baum, A l v a r e z , £ Cobb , 1974; Cobb e t a l . , 1975, Nage l e t a l . , 1975; S c h a f f e r £ C o b b , 1975) t h a t s u r v i v o r s o f v e n t r i c u l a r f i b r i l l a t i o n a r e p r o n e t o sudden d e a t h f rom s i m i l a r c a u s e s w i t h i n 24 months o f t h e i r d i s c h a r g e f r om h o s p i t a l f o l l o w i n g t h e i n i t i a l e v e n t . Nage l e t a l . (1975, p. 218) s p e c i f i c a l l y s t a t e t h a t t h i s i s so i n s p i t e o f w h e t h e r o r no t t he p a t i e n t s were p r e s c r i b e d a n t i a r r h y t h m i c m e d i c a t i o n s on d i s -c h a r g e . In a number o f a r e a s t h e n , p a r t i c u l a r l y n e u r o l o g i c d e f i c i t and 18. long-term survival rates for initial survivors of cardiac arrest, a note of caution is sounded. However, even reports of failures are useful: Understanding of the EMA structure and planning of successful intervention would be far better served by a few analytic case histories of failures and an honest appraisal of the underlying reasons than by the present potpourri of unconvincing success stories. (Gibson, 1974a, p. 14) EVALUATION STUDIES OF PREHOSPITAL CORONARY CARE Evaluation of emergency services is challenging, since the system is such that it attracts personalities to whom forceful action is much more attractive than is careful evaluation (Willemain, 1977)- The goal of an emergency service system is "to prevent death, disability, and suffering in persons with injury or acute illness" (ibid., p. 2). Do paramedic programs providing advanced life support outside hospitals actually achieve this? To answer the question we can choose to focus on input measures for the system, process measures, and/or output measures, but defining appropriate measures and developing consensus about their appropriateness is difficult. Examples of input measures are the number of ambulances per 100,000 population, number of trained attendants staffing each ambu-lance, number of runs per ambulance, and patient need (clinical need for services which are provided by ambulances and ambulance crews). The comparative value of such measures is questionable because ideal standards are not well defined and may vary, depending on local c i rcumstances. 19. Examples of ambulance service process measures are the time from receipt of a call to arrival at the scene of the incident, type of aid administered by ambulance personnel to patient request-ing assistance, appropriateness of calls requesting the ambulance (Gibson, 1973, 1974b; Willemain, 1977). While it is useful to have these measurements, they require interpretation. For example, a dispatch system which involves questioning the caller in order to dispatch a suitable vehicle to the site may result in a longer re-sponse time on average than if the dispatcher simply took the call and dispatched a vehicle immediately. A low response time, there-fore, may not reflect an efficient dispatching system (Willemain, 1977). Process measures reflect the actual use of services and the actual care received (Gibson, 1974a). They evaluate the dynamics of providing the service, rather than its outcome. Examples of outcome measures are mortality rates, morbidity and residual disability measures. Willemain (1977) notes that Gibson raised some salient issues around these measures: mortality rates reflect more than just ambulance service performance, and we do not have effective ways of controlling for intervening variables; mortality rates have in the past not correlated well with subjective impressions of quality of service (ibid., p. 8); when mortality rates improve, residual disability measures may register increases. In light of such problems Willemain (1977) pointed out Gibson's observation that: There is little in the literature to disprove the hypo-thesis that the emergency system is treating patients 20. whose survival is s o l e l y a function of the i r condition and that EMS expenditures only influence when and where the death takes place, (p. 8) While we are able to measure how many people become i l l or are injured and die, and from what causes, we do not have a clear picture of the range of intervention strategies which could save l i v e s and avoid or reduce residual d i s a b i l i t y , and the costs associated with alternate intervention strategies (Gibson, 1974a). Nor do we measure the opportunity costs associated with dedication of scarce resources to r e l a t i v e l y i n e f f e c t i v e programs (Willemain, 1977). Surely these are important considerations for decision-makers. Despite these caveats, there are numerous reports in the l i t e r -ature of the impact of prehospital cardiac arrest programs on mortality rates for these patients. Eisenberg et a l . (1980b) reviewed 21 a r t i c l e s reporting on outcomes for programs in 15 locations within the United States. He noted that most studies were d e s c r i p t i v e and few made use of comparison or control groups. Though success rates for admission to hospital varied from 22 per cent to 65 per cent, and for discharges a l i v e from hospital from 3.5 per cent to 31 per cent, i t was d i f f i c u l t to interpret these differences. He described "lack of standard terminology, methodo-log i c a l unevenness, d e f i n i t i o n a l inconsistencies, and a vari e t y of formats used in reporting outcomes" (p. 236), and went on to say, The p r o l i f e r a t i o n of d i f f e r e n t terms, case d e f i n i t i o n s , methodologies, and reporting formats preclude e f f e c t i v e evaluation of paramedic programs. It is impossible to compare one program with another or against a commonly accepted standard, (p. 237) To illustrate the distortions which can result from this situation, he used data from one of his own studies: This study compared outcomes of cardiac arrests treated by paramedics and emergency medical tech-nicians (EMTs). The combined discharge rate for patients treated by both groups was 15 per cent. If cardiac arrests treated only by paramedics are considered, 22 per cent of patients were discharged from the hospital. If only witnessed cardiac arrests are considered, 28 per cent of patients were discharged. If only those cases in ventricular f i -brillation (VF) on arrival of the paramedic unit are considered, 30 per cent were discharged. Finally, if patients in VF are considered where cardio-pulmonary resuscitation (CPR) was initiated within k minutes of collapse and definitive care provided within 8 minutes of collapse, then 60 per cent of patients were discharged. (p. 237) In view of the potential for confusing results, Eisenberg went on to propose a uniform reporting system which would permit more accurate evaluation of the impact of paramedic programs on prehospital cardiac arrests, and ensure comparability of informa-tion coming from different geographic locations. A number of factors discussed in the literature do seem to be associated with likelihood of successful outcomes from cardiac arrest : - cause of arrest (Eisenberg & Bergner, 1979 ; Urban et al., 1981); - whether or not the event was witnessed (since un-witnessed events mean there is generally little chance of early intervention) (Bergner et al., 1981 ; Eisenberg, 1 9 7 9 a , 1 9 8 0 b ) ; - short time to definitive care (generally this is closely associated with availability of paramedics) (Eisenberg et al., 1979a, 1980b; Webster, 1980); and 22. - short time from collapse to initiation of CPR, which often means availability of bystanders will-ing and able to perform cardiopulmonary resuscita-tion until emergency services personnel arrive on the scene (Copley et al., 1977; Eisenberg et al., 1979a; Guzy et al., 1979; Lund £ Skulberg, 1976; Tweed et al. , 1980c). STUDIES OF OUTCOMES FOR CARDIAC ARREST VICTIMS TREATED BY PARAMEDICS In spite of the limitations described by Eisenberg and his colleagues which certainly appear valid, five studies of outcomes for cardiac arrest cases handled by paramedics have been chosen for more complete presentation here: 1. Diamond, Schofferman, and Elliot (1977) reported on paramedic runs in Torrence, California, (Los Angeles County), during a ten and one half month period ending in May 1975. Six paramedic fire rescue squads operate out of a single base hospital, though half of the cases which they attend are taken to other, closer, local hospitals. These paramedics appear to meet the criteria set out by the American Heart Association for advanced life support personnel. Seventeen patients from a total of 2,152 runs were judged to have died before the paramedics reached the scene, and resuscitation was not attempted for them. Fifty-six per cent of all runs were "non-critical", and most of these involved children or young adults. An additional 27 per cent had serious but non-1ifethreatening medical problems. One hundred twenty cardiac arrests from all causes oc-curred (.5.6% of total runs), and these will be discussed here, though the study does report on other types of cases as well. 23. Most of the cardiac arrest calls were to people in the 50-70 age group, and most were men (.98 of 120). One hundred twelve arrests were judged to be of primary cardiac etiology (93%), a n d response time for cardiac arrest calls was under k minutes, 70 per cent of the time. Ventricular f i b r i l l a t i o n (VF) was documented for 50 cases, and asystole for kO more. One hundred eight cases were found in arrest (90%), and 12 arrested during attendance by paramedics. Of the 108 people found in arrest, 30 survived to the emergency department, 2k were admitted to hospital, and 15 (lk% of the 108 cases) were discharged alive. Of the 12 cases arresting during attendance by paramedics, VF occurred in nine cases, five patients were admitted to hospital, and only one survived. Overall, 16 of 120 cardiac arrest patients 03%) handled by paramedics were discharged alive. The report does not mention the types of hospitals receiving cardiac arrest patients and possible differences between them in terms of their a b i l i t y to provide special cardiac care. No mention is made of whether or not incidents were witnessed, nor of the fre-quency with which bystanders provided lay CPR before emergency services personnel arrived. It is not clear what proportion of the cardiac arrests in the study community were attended by paramedic personnel. No comparison group was monitored to permit comparison of outcomes for patients attended by paramedics and patients who were dealt with in some other way. The study concludes, "The concept of intricate, prolonged stabilization in the f i e l d , while 24. suitable for the cardiac arrest victim...needs further study for other medical problems" (p. 4 6 ) . 2. Lauterbach, Spadafora, and Levy (1978) reported on success rates for Cincinnati paramedics with cardiac arrest victims from all causes. Here a cardiac arrest was defined as "oscilloscope diag-nosed ventricular fibrillation or standstill" (p. 356) . The study covered a one-year period, and success was defined as the percentage of patients for whom resuscitation was attempted who survived until discharge alive from hospital. No mention was made of the number or per cent of patients for whom resuscitation was not attempted. Seven mobile intensive care units (MICU) attached to four different fire departments provided coverage within the greater Cincinnati area. MICUs were staffed by paramedics who met the American Heart Association's standard for advanced life support personnel. Basic life support occurred infrequently for patients attended by MICU personnel before the arrival of the unit. Initial resuscita-tion rate (alive on arrival at the hospital emergency department) was 32.7 per cent (48 of 147 cases). Twenty-two patients were dis-charged alive from hospital (15%) and 26 (18% of the total) died in hospital. The age group for which resuscitation was most successful was 50-59 (35%). and men in this group had a success rate pf 40 per cent. Only 35 patients (25%) were women. Over all age groups, the success rate for women was 8.6 per cent, compared to \7 .k per cent for men 2 5 . in the study. A number of important issues were not discussed in this report: average response time for paramedics; proportion of all cardiac arrest cases included in the study; number and types of hospitals receiving victims after resuscitation; and the proportion of cases where the collapse was witnessed. There was no control or compari-son group in this study. 3 . Liberthson, Nagel, Hirschman, and Nussenfeld (.197**) reported on 301 documented ventricular fibrillation cases which occurred over a kl month period in Miami, and which were attended by fire department rescue squad personnel. All causes of ventricular fibrillation were included in this study. Only one-third of the patients in this study were found to have had symptoms which would have permitted intervention before col 1 apse, and the rest collapsed virtually instantaneously. Seventy-five per cent of the patients were men, and the average age of the study group was 6 3 . Eighty per cent of emergency cases were reached within k minutes of the call for assistance. Squad personnel qualify as advanced life support personnel using the American Heart Association's definition. For this study success was defined as admission alive to hospital. The hospital had an intensive care unit and squad personnel had voice contact while at the scene and en route with a doctor in the intensive care unit. Of 301 study patients, 102 (3*t%) could not be resuscitated 26. and 199 (66%) responded initially to defibrillation. Of the 199, 101 (3k% of the whole group) were hospitalized, and 98 died before admission. Of the 101 hospitalized, 59 patients died in hospital and kl ()k% of the whole group) were discharged alive. Sixty per cent of the survivors discharged from hospital returned to their former way of life, and the rest had varying degrees of residual neurologic impairment. Antiarrhythmic drugs were prescribed for 29 of kl patients who were discharged alive after their cardiac arrest. Twenty-two patients were still alive by the time the article was written--a mean survival time of 8.3 months. Of the 20 patients who died after discharge from hospital, 12 did so suddenly, and 10 of the 12 had been discharged on anti-arrhythmic drugs. No mention was made of the frequency with which lay CPR was performed before the arrival of the rescue squad, and the proportion of the arrests which were witnessed is unclear. The report does not contain information about the proportion of cardiac arrest cases attended of all cardiac arrests occurring in the area, and does not discuss unsa1vageable cases. This study had no control or comparison group. k. Closer to British Columbia, Cobb, Baum, Alvarez, and Schaffer (1975) reported on the Medic I program's success with ventricular fibrillation cases in Seattle. Characteristics of the Medic I system are: 2-5 minute (mean 3 minutes), tiered response, public 27. education about heart attack, cardiopulmonary resuscitation, and availability of emergency response personnel, direct coronary care unit admission for appropriate patients, resuscitation from circula-tory arrest, and early intervention with other life-threatening occurrences. Paramedics meet the standards for advanced life support personnel suggested by the American Heart Association. Access to the emergency system is via a 911 telephone number. Over 80,000 citizens in Seattle received CPR training, and in this study nearly 20 per cent of the resuscitations attempted by Seattle paramedics had been preceeded by lay CPR. During the four year period covered by the study, a total of 1,106 cardiac arrest patients with ventricular fibrillation were attended by paramedics. The number of these which were witnessed was not stated. There were 511 patients in the first 2 years of the study, and 595 in the second 2 years. There was a statistical-ly significant improvement in the per cent of patients initially resuscitated and in the per cent of patients discharged alive from hospital when the first period results were compared with second period results. The rate for initial resuscitation increased from 34 per cent to 43 per cent, and the rate for live discharges from hospital increased from 11 per cent to 23 per cent. The authors suggest several reasons for the improvement: average response time was shortened in the second period by sending a fire truck when other emergency vehicles could not reach the scene within 5 minutes; firemen were given more CPR training; increasing numbers of Seattle 2 8 . c i t i z e n s had c o m p l e t e d CPR t r a i n i n g as t he s t u d y p r o g r e s s e d . Two hundred t h i r t y - f o u r p a t i e n t s s u r v i v e d a t o t a l o f 2hS s e p a r a t e o c c u r r e n c e s o f v e n t r i c u l a r f i b r i l l a t i o n (22.5% o f t h e t o t a l ) ou t o f h o s p i t a l , and were d i s c h a r g e d home. Two hundred seven were f ound i n a r r e s t , and 38 a r r e s t e d d u r i n g a t t e n d a n c e by t h e p a r a m e d i c s . One hundred e i g h t y - t h r e e s u r v i v o r s were m a l e , and 51 were f e m a l e . A v e r a g e age o f s u r v i v o r s was 59-8 y e a r s . The o n e -y e a r m o r t a l i t y r a t e f o r p a t i e n t s d i s c h a r g e d a l i v e f r om h o s p i t a l was 30 pe r c e n t , and the t w o - y e a r m o r t a l i t y was 41 pe r c e n t . The s t u d y found t he l o n g - t e r m s u r v i v a l r a t e s f o r p a t i e n t s w i t h p r i m a r y v e n t r i c u l a r f i b r i l l a t i o n t o be p o o r e r t h a n f o r o t h e r p a t i e n t s who had e x p e r i e n c e d v e n t r i c u l a r f i b r i l l a t i o n . T h i s s t u d y d i d not have a c o m p a r i s o n o r c o n t r o l g r o u p . 5. The l a s t s t u d y t o be r e p o r t e d he re i s t h e most e l e g a n t i n d e s i g n . E i s e n b e r g , B e r g n e r , and H a l l s t r o m (1980a) r e p o r t e d ou tcomes f o r p a t i e n t s w i t h o u t - o f - h o s p i t a l c a r d i a c a r r e s t s ( d e f i n e d as p u l s e l e s s c o n d i t i o n c o n f i r m e d by an emergency m e d i c a l t e c h n i c i a n (EMT) o r p a r a m e d i c ) c a u s e d by h e a r t d i s e a s e , o c c u r r i n g i n subu rban a r e a s j u s t o u t s i d e S e a t t l e , W a s h i n g t o n . T h i s g roup r e p r e s e n t s 80 pe r c e n t o f a l l c a r d i a c a r r e s t s a t t e n d e d by emergency s e r v i c e s p e r s o n n e l i n t he a r e a s . The s t u d y c o v e r e d a t h r e e - y e a r p e r i o d w h i c h was d i v i d e d i n t o two p a r t s — t h e f i r s t 17 m o n t h s , and the second 19 months i n l e n g t h . In p e r i o d 1, t h e s t u d y communi ty had EMT s e r v i c e s o n l y . In p e r i o d 2, p a r a m e d i c , s e r v i c e s were a d d e d , and s o t h e s t u d y 29. community then had both EMT and paramedic coverage. Paramedics in this study seem to meet the criteria for advanced life support personnel. Two adjacent communities served as comparison groups for the study. The first had EMT services only (data from this community covers 2k months, since significant changes occurred after that in their emergency response system). The second had both paramedic and EMT services for periods 1 and 2. Study and comparison communi-ties were found to be similar on such variables as sex ratio and proportion of citizens over 65. Most of the population in these communities were Caucasian. In the study community during period 1 with EMT service only, kl of 223 patients (19%) were admitted alive to a coronary care or intensive care unit, compared to 117 of 3^9 in period 2 (3k%) when both EMTs and paramedics treated victims. The corresponding dis-charged alive rates for the two periods were 7 per cent of the total patient group (15 patients) and 17 per cent (60 patients) respective-ly. Both of these improvements were found to be statistically sig-nificant. Time to definitive treatment decreased from a mean of 27.5 minutes in period 1 to a mean of 7-7 minutes in period 2. In the first comparison community which had only EMT services for 2k months, the rate of admission alive in period 1 was 11 per cent, and in the second period for this community was 2k per cent. This difference did not prove to be statistically significant. The discharged alive rates for the same periods were k and 3 per cent of the total patient group. 30. In the second comparison community which had both EUT and paramedic service for both periods, the rates of admission alive were 37 per cent in period 1 and 36 per cent in period 2. The discharged alive rates were 2k per cent of the total patient group (.181 patients) in period 1, and 19 per cent (of 182 patients) in period 2. The study reported that time to initiation of resuscitation, number of witnessed arrests, type of cardiac rhythm, person giving resuscitation, medical practice, and available hospital facilities remained- essentially the same over the length of the study. The major change identified was decreased time to definitive care in the study community after introduction of the paramedics. The authors believe that this likely accounted for the observed improvement in outcomes for cardiac arrest victims in the study community from period 1 to period 2. They found also that most of the patients who survived to discharge were patients for whom ventricular fibril-lation caused the cardiac arrest. The article cautions that these results may apply only for similar services provided in geographically similar communities. Generally speaking, the Lower Mainland area of British Columbia meets these criteria, and it is felt that results achieved by British Columbia's paramedics with cardiac arrest victims whose arrests were caused by heart disease can usefully be compared with the results documented in this study, although the case definitions are somewhat different for the two programs. OTHER LITERATURE Additional mention of existing literature Chapter IV, Study Methodology. 32. CHAPTER I I I DEVELOPMENT OF THE ADVANCED LIFE SUPPORT PROGRAM IN B.C. In 1968 a group of physicians interested in practicing emerg-ency medicine banded together to form the Columbian Emergency Physicians and offered to provide Royal Columbian Hospital with 24-hour-a-day emergency room coverage. Their offer was accepted, and in the course of providing this coverage, the physicians came into contact with ambulance attendants, firemen and others who were providing prehospital emergency care within the local community. A basic tenet of emergency room medicine is that the emergent patient should receive appropriate treatment as early as possible during the course of an incident in order to increase the potential for successful management of the problem. The "stabilize and trans-port" approach had already been shown to be much more successful than the "grab and run" approach with emergent patients. Vancouver had the example of Seattle's successful prehospital care program, and the emergency physicians working at Royal Columbian Hospital felt that a similar program could and should be implemented here. The chief question was, which group currently providing prehospital care should be offered paramedic training and support by emergency physicians. The emergency physicians felt that there were clear differences in the quality of care being provided to emergent patients at that time by the various groups providing emergency services. Ambulance 33. personnel, as part of their own efforts to upgrade themselves and professionalize their occupation, had created and/or taken advantage of educational opportunities which came their way—often on their own time and substantially at their own expense. They had asked to be taught certain specific skills, or joined classes held to train other groups, such as the intensive care unit courses offered at Vancouver General Hospital. This enthusiastic group, providing ambulance coverage as their primary responsibility, seemed the obvious choice for support by the physician group. Metropolitan Ambulance Company, which employed a large number of attendants and ran a major ambulance service, fully supported the idea (verbal communication: H. Parkin, the emergency physician who initiated the advanced life support program). From a large number of applicants for training the physicians chose nine candidates, each of whom had many years of experience as an ambulance attendant. Their experience had given them tremendous skill in assessing medical emergencies, and in addition they already had a substantial base of theoretical knowledge about emergency care because of the various training courses which they had attended. People connected with the Royal Columbian Hospital generally supported the plan to train paramedics at the hospital, and most felt that such a program was overdue in the Vancouver area. A multi-disciplinary committee was struck to discuss the plan for training paramedics and having them work out of the hospital. Members had no philosophical bias against training non-physicians to provide 34. advanced care in the community to emergent patients. Because of their familiarity with the ambulance service and personnel, it was not difficult to obtain the necessary medical staff approval for the paramedic program. One of the members of the Columbian Emergency Physicians group was also a member of the British Columbia Medical Association's Traffic and Safety Committee, which was chaired by a Victoria pedia-trician, P. Ransford. This committee dealt with issues in the area of emergency services within British Columbia. The proposal that a paramedic program be established and approved was put before the com-mittee, and eventually received committee endorsement. After a pre-sentation to the BCMA's Board of Directors, the program received Board support too. The proposal then went to the College of Phy-sicians and Surgeons of British Columbia and, although this group made it clear that it did not want to be the licensing body for paramedics, it gave its approval for establishment of the paramedic program (verbal communication: H. Parkin, 1978). The biggest problem was the legal one. Some paramedic activi-ties such as endotracheal intubation and administration of drugs would not be legal under the Medical Act. Even the training of people to perform these activities would require special approval from the Council and the Minister of Education (British Columbia, 1979). Although it might have been possible to change the Medical Act to overcome these problems, it was felt that this would be met with 3 5 . considerable resistance and would be a cumbersome and very long-term undertaking. However, since the College of Physicians and Surgeons of British Columbia had approved the program and informally agreed not to prosecute people associated with it for either of the two issues of concern, the criminal law problems were felt to be manageable. Obtaining protection from civil law prosecution, however, proved to be more difficult (verbal communication: L. Vertesi, 1 9 7 8 ) . Since paramedics had to be held responsible for the results of their actions in cases of negligence, it was impossible to ob-tain complete protection against the threat of lawsuits resulting from their work. Royal Columbian Hospital was able to obtain in-surance to protect the hospital and the paramedics while they were working within the hospital, but more was needed. Insurance to give additional protection to physicians and paramedics involved in the program was necessary. Once the BCMA and the College of Physicians and Surgeons of British Columbia had approved the program, the physician group ap-proached the Canadian Medica1-Lega 1 Protective Association, asking whether or not the insurance for physicians would protect physicians in the event of a lawsuit arising from involvement with the paramedic program. Although there was no immediate answer from the Association, planning for the paramedic program began. On May 2 3 , 1 9 7 3 , training of the first group of nine paramedics started. Then, part way through the course, the physician group 36. received a letter indicating that its insurance would not cover activities associated with the paramedic program. This left both physicians and paramedics in jeopardy for activities of the para-medics outside the hospital. It was decided that, since it seemed likely that an Emergency Health Services Commission would be estab-lished within a reasonable period of time and that it would be able to help overcome some of the insurance problems, it would be wise to wait for this before attempting to implement the paramedic ambulance service. At the end of their training program the paramedics re-turned to their stations as regular ambulance attendants, unable to use much of what they had learned during paramedic training. The Emergency Health Services Act, passed in May 197**, result-ed from the Foulkes Report (1973), commissioned by the New Democratic Party government after it was elected in 1972. Foulkes had been an administrator at Royal Columbian Hospital, and was familiar with the Columbian Emergency Physicians group and the proposal for paramedics for British Columbia. The Act, and the regulations accompanying it, provided for establishment of a single provincial ambulance service (Metropolitan Ambulance Company was soon taken over by the new provincial service) and officially permitted emergency medical assistants to administer medical care in appropriate circumstances. With this, the Commission was able to obtain the necessary insurance for paramedic activities, and the advanced life support program was reactivated. Since the paramedics had completed training many months earlier and had not been able to practice their special 3 37. skills in the interim, they were given a refresher course and another set of examinations. (n April 1975, British Columbia's first para-medic vehicle, working out of Royal Columbian Hospital, New Westminster, began accepting emergency calls. The first paramedic training program focussed primarily on teaching emergency cardiac care, since it was felt that as much as 70 per cent of calls attended by advanced life support personnel would be for patients with this type of complaint (verbal communica-tion: L. Vertesi). As time passed, however, it was found that they dealt with a much broader spectrum of medical emergencies, so the training course was altered to reflect these other responsibilities. Currently British Columbia's advanced life support personnel receive approximately 1,800 hours of instruction and supervision over an 18-month period. After successful completion of their examina-tions, they are able to administer drugs, start I.V.s, defibrillate patients, interpret arrhythmias and perform endotracheal intubation. Their vehicles have advanced communication systems for dispatch, and while en route they can speak with receiving hospitals through dispatch. Thus they are comparable to the paramedics in and around Seattle, and conform to the American Heart Association's definition of advanced life support personnel (Standards for Cardiopulmonary Resuscitation, 197*0. EMA Ms in British Columbia complete 350 hours of training which includes CPR to the basic cardiac life support standard of the American Heart Association. 38. At the time this evaluation study was undertaken, paramedics, worked out of three ambulance stations in the Lower Mainland, and provision was being made for another class of trainees to begin its studies. Graduates from this class would provide replacements for staff who had left the paramedic service, and would, in addition, provide staff for a fourth vehicle to be located in Vancouver, since call volumes in Vancouver were high. Collection of study data was discontinued June 1, 1980 when this class began its clinical placement on the three well-established vehicles, since it was felt that the performance of class members, at least T nt ial1y, might be different from that of service veterans, and might therefore distort the findings. Twelve general hospitals in the Lower Mainland received cardiac arrest patients from the ambulance service during the course of this study, and the vast majority of patients treated by ambulance personnel went to emergency departments which were open 2k hours a day with physicians in the department or on call for emergencies. 39. CHAPTER IV  STUDY METHODOLOGY The Emergency Health Services: Commission in 1979 had a total of 19 ambulance stations located throughout the Lower Mainland of British Columbia, providing service to 1,268,000 people (Statistics Canada, 1981) living within an area of approximately 10,300 square miles (British Columbia, 1981). The area which is known as the Greater Vancouver Regional District composes 92 per cent of this area, and is urban or suburban in nature. At the time of this study (.September 15, 1979 to June 1, 1980) only three ambulance stations had paramedic vehicles and staff in addition to regular ambulances (figure 1). The remaining 16 stations providing service had regular ambulances only. Each station was associated with at least one hospital in its area which was committed to providing emergency care to the surrounding commun-ity. Generally paramedic vehicles had a sufficiently large volume of appropriate emergency calls that they could not respond to calls out-side the boundaries of their territories. Cardiac arrest calls, therefore, which occurred in areas which did not have paramedic coverage, or in paramedic areas when the paramedic vehicle was occupied with another call, normally would be handled by EMA Ms alone or with the assistance of the Fire Department. These cardiac arrest calls handled by EMA Ms without the assistance of EMA Ills served as a comparison group for paramedic unit performance in this 40. FIGURE I: GEOGRAPHICAL AREAS WITH AND WITHOUT ADVANCED LIFE SUPPORT VEHICLE COVERAGE IN THE LOWER MAINLAND OF BRITISH COLUMBIA With Advanced Life Support Vehicle Coverage ** Without Advanced Life Support Vehicle Coverage ** Note: Boundaries for the advanced life support vehicle serving New Westminster are flexible--they may be sent to Coquitlam, North Delta, North Surrey, and even Port Coquitlam, depending on their distance from the scene, call volumes, and patient need. 41. study of outcomes. It should be noted, however, that there was no independent confirmation by electrocardiogram that the cases judged by EMA Ms to be cardiac arrests were so in fact. It could also be that certain patients in ventricular fibrillation were not recog^ nized by EMA lis as being in urgent need of definitive care as early as EMA Ills would have realized it. Although it is generally accepted that the ideal model for evaluation research is the randomized, controlled trial, use of the model is rare when the research is being carried- out in a health care setting. In the field of health care, when it is generally accepted that one treatment is substantially more effective than another for a given problem, whether or not this has been proved experimentally, it is considered politically and morally unethical to randomly assign patients to one or the other treatment program (Killip, 1979; Rossi & Wright, 1977). Researchers attempt to ensure the closest approximation to the ideal, given the circumstances (.ibid.). The requirements of experimental designs do not neces^ sarily mean that service be withheld from anyone. The main requirement is that the program or project to be evaluated be different from the services made available to the control groups....A control group might be given traditionally available services." (Rossi £ Williams, 1972, pp. 31-32) Although this design does not permit definitive statements about the causes of outcomes which are identified, it does permit statements about associations between study variables and the outcomes which have been observed. kl. The initial proposal was to measure outcomes at two points in time for cardiac arrest patients treated by the ambulance service: (a) survival to arrival at hospital, and (b) survival to discharge alive from hospital. It was deemed accepteble to study only cardiac arrest victims, since some authors have claimed that the only cases for which paramedics clearly have an impact on mortality rates are those wTth cardiac arrests (Eisenberg et al., 1980b ; Urban et al., 1 9 8 1 ) . During the course of the study a substantial problem of mis'-classification was discovered. There was doubt about whether crews from different stations were recording survival to arrival at hospital in the same way. Some would call a patient dead on arrival at hospital when the patient was so pronounced by the emergency department physician, while others would consider a patient who was accepted into the emergency department for examination, even though he appeared to be dead, to have died while in the emergency depart-ment, rather than having been dead on arrival. Emergency depart-ments contributed to the problem since some were so busy that they could not take a pulseless patient and attempt to resuscitate him if there was virtually no chance that he would survive, while other emergency departments would work on the patient for up to half an hour before deciding that he really had been dead on arrival. Because of the possible misciassification by ambulance crews and the differing policies among emergency departments, it was decided to use admission to hospital ward or special unit as the first point at which outcome would be measured. Thus the "died before 43. admission" category includes those dead at the scene, those who died in transit, and those who died in the emergency department. Outcome measures for this study, then, are mortality rates. Some of the problems of using mortality as an outcome have been discussed earlier: residual disability is not measured; the rates are contaminated by other variables which Intervene during the course of treatment, such as quality of emergency department care, the coronary care unit and general hospital care in. the receiving hospital, and severity of the medical problem experienced by study patients (Gibson, 1974a, 1974b; Willemain, 1977). Furthermore, Willemain has pointed out that mortality rates for one tracer disease which is being studied may not correlate well with outcome measures for other conditions with which the same personnel are expected to deal. Mortality measures generally ignore successful outcomes for patients whose conditions are not likely to result in mortality, and make no attempt to measure morbidity differences which may exist. Lastly, it has been pointed out that if an ambulance service is relatively ineffective, patients will die before they arrive at the hospital, but if it is very good, more marginal patients will be transported alive, but will die in the ambulance or at the hospital (Outcome Measurement Panel, 1975). In these cases, the main thing which has been altered is where the patient died, not the likeli-hood of this outcome (Gibson, 1974b). (it should be noted, however, that Cobb (p. 159 in Myerburg, 1979) suggests that this may not kk. always be so. Some patients who have clearly died will be taken directly to the coroner's facility, since paramedics will feel more comfortable making a decision that a death has occurred, and these patients will never reach the hospital.) Since this study was meant to be only an initial evaluation of the paramedic program, and since many other paramedic programs throughout North America were reporting success based on survival measures for patients experiencing cardiac arrests, it was decided in spite of the limitations inherent in using mortality measures, to assess first patient survival to hospital ward or special unit, and second to discharge alive from hospital, as criteria for evaluation of the performance of British Columbia's paramedic ambulance service. That is to say, the independent variable for this study is the availability of paramedic (EMA III) care for cardiac arrest victims, and the dependent variable is survival. DISPATCH SYSTEM All emergency calls to the ambulance service are received at a central dispatch office. The calls can come to any of four telephone numbers: 1. the Emergency Health Service Commission telephone number, though few calls would come on this line, 2 . the general emergency telephone number (911) which has been in use in Greater Vancouver since 1977, 3- the emergency telephone number listed for the ambulance service in the telephone directory, or k. the old Metropolitan Ambulance telephone number. 45. When the 911 telephone number is dialed, an operator based at Police Department headquarters answers and asks, "Fire, Police, or medical emergency?". She then rings the call through if it is for the Fire Department or the Provincial Ambulance Service. Ambulance dispatch has direct telephone lines to Fire Department dispatch offices serving the same areas where ambulance stations are located, and to emergency departments in most of the hospitals which regularly receive emergency patients from the ambulance serv i ce. At the time of this study, dispatchers were required to have spent several years as ambulance attendants before moving into the dispatch office. One dispatcher per shift took all incoming calls, recorded the information, asked questions to clarify the situation so that he could determine the priority of the call and the type of vehicle which should respond if there was a choice, and then passed the information slip to another dispatcher who would actually dis-patch the ambulance crew nearest the location of the incident. Frequently it was extremely difficult to determine the urgency of an incoming emergency call, since much of the information was being provided by an upset family member or bystander. The skill of the dispatchers was in their ability to evaluate these emergency calls for an appropriate response. All calls to the emergency lines of the ambulance service were recorded on tape. The slip which the dispatchers completed contain-ed information about the incident as follows: sex and age of the 46. victim, symptoms, caller, time of receipt of call, time of dispatch of vehicle, type of vehicle sent, level of response (sirens used?), station responding, time the vehicle reached the scene, time the vehicle left the scene, time the vehicle reached the hospital, receiving hospital, time the vehicle was free to respond to another call. When these dispatch slips were matched with the Crew Reports (also known as Form I Is and basic call sheets), all the information which the ambulance service collected about regular ambulance calls was available. HANDLING OF CARDIAC CALLS During this study, any incident suspected of being cardiac-related would be assigned to a paramedic unit if one covered the area. A regular ambulance would be dispatched at the same time to assist, and the Fire Department dispatch office would be informed of the call. Most fire stations had fire and safety units. Per-sonnel on these units had basic industrial first aid training, and carried first aid kits, oxygen therapy units and pulmonators with airways in their vehicles, in addition to the jaws of life and oxygen and masks for fire fighters. Fire Department staff would go to the scene and establish control while waiting for the ambulance crew(s) which they knew would be there as soon as possible. Ideally, then, the response to an urgent cardiac call was as fo11ows: - If the incident happened in an area with paramedic coverage, the regular ambulance and the paramedic 4 7 . vehicle would be dispatched to the scene, and the Fire Department would be notified of the incident. Since there were more Fire Department stations than amhulance stations, and more ordinary ambulances than advanced life support vehicles, generally the rescue and safety unit would arrive first, the EMA II ambulance second, and the advanced life support ambulance third. EMA Ms would take over treatment of the patient from Fire Department staff when they arrived, and would do whatever they could to help. EMA Ills in turn would take over when they arrived, and EMA Ms would remain to assist in any way they were asked. - If the incident occurred in an area without paramedic coverage, or if the paramedic vehicle was not free to respond to the call, then an EMA II vehicle would be dispatched to the scene and the Fire Department noti-fied. If appropriate, the advanced life support vehicle would be sent when it became free, unless the EMA Ms had already left with the patient to go to the hospi tal. This tiered response system was designed to ensure that skilled help would reach the victim as quickly as possible. STUDENT CLERKSHIP In the fall of 1977 an inital evaluation of the cardiac care 48. component of the paramedic ambulance service was proposed. Although it would have been possible to carry out a before/after evaluation study when the advanced life support program was first established, this had not been done. The proposed study, therefore, would be the first formal evaluation of the paramedic service. With an evaluation in mind, a clerkship was arranged with the Emergency Health Services Commission in Vancouver, for a student in the M.Sc, Health Services Planning program at the University of British Columbia. The purpose of the clerkship was to determine whether an evaluation study was feasible using existing ambulance service and other records, or whether a prospective study with special data collection forms would be necessary. For a two-week period, all calls from four ambulance stations in the Lower Mainland were examined. Two of the four stations had both paramedic and regular ambulances. The other two stations had regular ambulances only. These latter two stations were selected by the Chief Dispatcher for their similarity to the two stations which had paramedic crews. All the Crew Reports (see Appendix B) from the ambulance service were examined for the four stations in the study. The types of calls to which the crews from these stations responded were noted, and the call sheets from calls to suspected heart attack patients were kept separate for further analysis. The Medical Director of the Advanced Life Support Program established the criteria for identifying likely heart attack cases, and the Crew Reports from 49-from these runs were matched with the appropriate dispatch, s l i p s . In addition to t h i s , a l l dispatch s l i p s for the study period were examined for the four stations, to determine whether or not heart attack c a l l s could be i d e n t i f i e d which had been missed by examining only the Crew Reports. For a l l i d e n t i f i e d cases, information about f i n a l outcomes was requested and received from Medical Records Deparments at receiving h o s p i t a l . This i n i t i a l examination of ambulance service records, however, showed that in too many cases some essential information which would be needed for the evaluation study was missing. This meant that the study would have to be designed and carried out prospectively, in order that the c a l l record would be complete enough to make analysis pract ica1. For the prospective study Crew Reports, dispatch s l i p s , and the special cardiac arrest forms which EMA I l l s were required to complete for such c a l l s because of the special procedures which they use, were c o l l e c t e d . In addition, a special cardiac arrest study sheet (Appendix C, Part 1) for EMA Ms to complete was designed with Dr. Vertesi's help, so that i t would be possible to capture for EMA II cardiac arrest c a l l s some of the information routinely provided by paramedics. Approval for research involving human subjects was requested from the University of B r i t i s h Columbia in the spring of 1978 , and was received in a l e t t e r dated July 2 4 , 1978 (Appendix D). 50. INITIATION OF THE PROJECT Discussion was held early in the summer of 1979 with the Royal Columbian/Douglas College Joint Education Venture group, which agreed to provide some financial and clerical support to the project. They were interested in the work of the ambulance service since they provided some of the training for ambulance personnel, but their particular interest in the project was in the advantage that by-stander CPR gives to likelihood of successful outcomes in cardiac arrest incidents since they provided instructors for and community education courses on cardiopulmonary resuscitation. The ambulance attendants' union (C.U.P.E., local 873) was approached for its support for the study. This, was essential since EMA Ms were to be asked to complete " special study data sheets for cardiac arrest cases which they attended. The requested support was quickly received, and the union representative offered to mail a letter to all union members in the Lower Mainland describing the purpose of the study and requesting cooperation with it. Further, as requested, the union representative arranged for the researcher to meet with delegates from each of the stations which would be involved in the study, so that the purpose could again be explained, the special data collection form discussed, and arrangements made for the representatives to call the researcher with any questions or problems which arose. These meetings took place in late August and early September 1979, forms were distributed to all stations, and data collection started on September 10, 1979- The first five 51. days were considered a t r i a l period, and information from t h i s period was not included in the f i n a l data set. There were very few questions about use of the forms, and at 12:01 A.M., September 15, 1979, c o l l e c t i o n of data to be used in the study began. EMA Ms were asked to complete a study data sheet in addition to t h e i r Crew Report for a l l cardiac arrest c a l l s which they attend-ed, regardless of whether or not EMA I l l s also attended the patient, provided only that there was reason to believe that the arrest was r e l a t i v e l y recent. Patients who appeared to have been dead for some time were therefore excluded from the study since they were not candidates for salvage. Dispatch s l i p s indicated whether or not there was a double response for each of the c a l l s , and receipt of information from both EMA Ms and I l l s served as a check that a l l cardiac arrest cases attended by ambulance service personnel were being i d e n t i f i e d in the data c o l l e c t i o n system. The EMA II form, however, was discarded when EMA I l l s attended the same case, unless i t was required in order to complete information for the EMA III report. For study purposes cases with double response were a t t r i b u t -ed to EMA I l l s . At the end of November a l l crew reports and dispatch s l i p s for a two-week period in early November were examined to determine whether or not some cardiac arrest c a l l s were being missed. As far as could be determined on the basis of this check, a l l cardiac arrest cases were being reported by either an EMA II special study form or the regular paramedic cardiac arrest report form. 52. PROBLEMS WITH DATA COLLECTION In J a n u a r y i t was o b s e r v e d t h a t few. c a s e s had been r e p o r t e d f rom two o f t he ambu lance s t a t i o n s s t a f f e d by EMA l i s o n l y . T h i s was drawn t o t h e a t t e n t i o n o f t he u n i o n r e p r e s e n t a t i v e who was a s k e d t o t r y t o d e t e r m i n e t h e c a u s e . A f t e r i n v e s t i g a t i o n , he i n d i -c a t e d t h a t s t a f f i n t h e s e two s t a t i o n s were b a s i c a l l y u n w i l l i n g t o p a r t i c i p a t e and t h a t a p p e a l s f o r t h e i r c o o p e r a t i o n by u n i o n o r E . H . S . C . r e p r e s e n t a t i v e s wou ld be u n l i k e l y t o be h e e d e d . The two s t a t i o n s i n q u e s t i o n were l o c a t e d i n a r e a s o f downtown V a n c o u v e r w i t h h i g h c a l l v o l u m e s . One was a S k i d Road a r e a i n t he c e n t r e o f t he c i t y where ambu lance p e r s o n n e l d e a l t w i t h " t o u g h c h a r a c t e r s " , many d e a t h s , and a l a r g e number o f i n a p p r o p r i a t e c a l l s f o r an a m b u l a n c e . Outcomes f o r c a r d i a c a r r e s t s e x p e r i e n c e d by r e s i -d e n t s o f t h e S k i d Road a r e a wou ld no t l i k e l y be r e p r e s e n t a t i v e o f ou tcomes f o r t he g e n e r a l p o p u l a t i o n because o f a v a r i e t y o f c o m p l i -c a t i n g f a c t o r s a s s o c i a t e d w i t h t h e i r l i f e s t y l e s , even i f d a t a had been c o l l e c t e d f o r a l l t he c a s e s i n t h i s a r e a . W h i l e a l l c a s e s w h i c h were h a n d l e d by EMA I l l s were i n c l u d e d i n t he s t u d y , some o f t h o s e h a n d l e d by EMA l i s o n l y were n o t , and t he e x c l u s i o n o f such c a s e s may tend t o o v e r s t a t e t he e f f e c t i v e n e s s o f EMA M s as a g roup i n t h i s s t u d y w i t h c a r d i a c a r r e s t c a s e s . The second a r e a , known l o c a l l y as t he West E n d , c o n t a i n e d a v e r y m ixed p o p u l a t i o n . It had numerous h i g h - r i s e a p a r t m e n t s w h i c h a t t r a c t e d bo th young b u s i n e s s p e o p l e and s u c c e s s f u l r e t i r e d c o u p l e s . A t the same t ime t h e r e were s u b s t a n t i a l numbers o f e l d e r l y p e o p l e 53. of limited means who had dwelt there for many years. It is a l s o an area where many of the -'street-wise" young and not^-so-young p l i e d t h e i r various trades. Generally speaking, i t is an area where one would expect a number of cardiac ar r e s t c a l l s to occur because of the number of seniors in the area, but the study was unable to c o l l e c t data on c a l l s handled by EMA l i s only. An examin-ation of crew reports for the area was c a r r i e d out once the problem was i d e n t i f i e d , but i t was impossible to t e l l from these documents in retrospect which cases might or might not have been appropriate study cases. They often contained b i l l i n g information and the word "co l l a p s e " but l i t t l e other information about the case. Since the only cases of interest were heart disease related cardiac a r r e s t s , i t was not c l e a r whether or not the cases of "collapse" should be included. They were therefore excluded. It can be hypothesized that some of the cardiac arrests occur-ring in the West End would be the result of trauma or overdoses, and these would have been excluded from analysis in any event. However the high c a l l volumes for the downtown and nearby West End areas l i k e l y mean that a number of appropriate EMA II study cases were lost to a n a l y s i s . A second s i g n i f i c a n t problem appeared la t e r in the data c o l l e c t i o n period. Contract renewal was being negotiated for ambulance service personnel, most of whom were unionized, in the spring of 1 980 and negotiations were not going p a r t i c u l a r l y w ell. O v e r a l l , the number of cardiac arrest cases being reported on EMA II. study forms dropped. The uni/on representative, at the request of the researcher, contacted station representatives again to try to rekindle enthusiasm for the study where it might have been flagging, but doubtless the animosity involved in long labor negoti-ations played a role in our having a reduced number of study cases from EMA lis. It has been assumed that in this instance the lost cases did not occur in any systematic way which would bias the results. EMA Ills continued to report in the usual way on their aggressive treatment of the cardiac arrest patients whom they attended. Cases for the study were collected until 12:01 A.M., June 1, 1980. Later that day the newest paramedic trainees commenced work with veterans on the advanced life support vehicles. During the data collection period from September 15, 1979 to June 1, 1980, a total of eight and a half months, hk3 cardiac arrest cases from all causes were identified for which the Provincial Ambulance Service had been caI 1ed. VARIABLES INCLUDED IN THE STUDY The following information was collected for each cardiac arrest cases attended by EMA I Is or EMA Ills or a combination of both: - date - receiving hospital - age of patient - sex of patient - type of ambulance(s) responding - station responding - time call was received - time vehicle reached the scene 55. - time to d e f i n i t i v e treatment for the patient - CPR being done on a r r i v a l of the ambulance? - i f so, CPR done by whom? - estimated time in arrest without CPR - patient found in arrest/arrested during attendance by ambulance personnel - presumed cause of arrest - patient d i s p o s i t i o n on a r r i v a l at hospital - patient d i s p o s i t i o n from emergency department - course a f t e r admission to hospital (died/ discharged a 1 ive) - length of h o s p i t a l i z a t i o n (See Appendix C, Part 2) These variables were chosen because they provided information which would lat e r f a c i l i t a t e comparison of the study and comparison group, or because they were factors which were i d e n t i f i e d in the l i t e r a t u r e as being p a r t i c u l a r l y relevant to outcomes from cardiac a r r e s t s . They were also variables which both groups of ambulance personnel could record regularly and r e l i a b l y , or which Medical Records Departments were w i l l i n g to provide on request. We did attempt to c o l l e c t information on whether or not the collapse was witnessed, but information on th i s was not provided with any reg u l a r i t y by EMA Ms completing the study data sheets, and th i s variable was excluded. IN-HOSPITAL COURSE Information regarding the in-hospital course of the patient was obtained by mailing a form i d e n t i f y i n g the date of the incident and the patient to Medical Records Departments of receiving hospitals. Some of the hospitals were accustomed to providing t h i s information concerning cases handled by EMA M i s , and the rest had previously 56. agreed to provide it if asked. Hospital information was obtained for all the cases for which it was requested. DATA PREPARATION After collection, the information was coded and eventually key-punched in preparation for analysis using the computer. Where the information was not available on a variable, it was coded as "information missing". Obviously in some cases no information was expected, e.g., for course in hospital for a patient who died before admission, and this, too, was specially coded. RELIABILITY AND VALIDITY ISSUES  Reliabi1ity "Reliability refers to the consistency of measurement; that is, the extent to which the measure would remain constant for any par-ticular subject if he were repeatedly tested under identical condi-tions" (Miller, 1975, p. 118). It is believed that most of the data recorded for the study was reliable. Although questions have been raised about the quality of data recorded by professionals and in medical records, little of the data which was collected for this study was open to interpretation: e.g., sex, responding station and times, and major outcomes such as admission to ward/special unit, died in hospital or discharged alive. In instances of double record-ing either by two EMA Ms both ensuring that the case was reported, or by an EMA II and an EMA III form for the same case, no evidence 57. was found of discrepancies in information (though one occasionally was more complete than the other). Validity There are two general types of threats to validity: threats to internal validity, and threats to external validity. The first is "the extent to which [measures] correspond to the 'true' position... on the characteristic being measured" (Selltiz, Wrightsman, & Cook, 1976, .p. 161). A variety of threats to internal validity are possible: (a) Hi story: If history is "any set of events other than the pro-gram, occurring between... two occasions of measurement" (Houston, 1972, p. 59), then history was not likely a threat to validity for this study. That is, there were no independent changes in manage-ment of or occurrence of cardiac arrests during the course of this study as far as could be determined. (b) Maturat ion: It is believed that this threat was controlled for by the fact that data collection did not continue into the period when newly-trained paramedics started providing care to patients in their community. All study EMA Ills were experienced advanced life support personnel. (c) Selection: It is at least conceivable that dispatchers might tend to send paramedics to cases where the chance for resuscitation appeared to be good, and EMA Ms to cases where the chance appeared poor. Dispatching in this fashion, however, was grounds for 58. dismissal, and during the time which the researcher spent in the dispatch o f f i c e no evidence of this sort of bias was found. It was f e l t that most recent out-of-hospita1 cardiac a r r e s t s were brought to the attention of one of the emergency services, and d i r e c t l y or through that service to the ambulance service, as Bergner et al . (1981) suggested. This type of selecti o n bias was not thought to be a problem for this study, except as described in section (d) following. (d) Experimental mortality: "The absence of data on some £cases^], may create observed differences between the experimental and the comparison groups" (Houston, 1972, p. 6 l ) . This may constitute a threat to v a l i d i t y for th i s study, since i t is impossible to know with certainty what e f f e c t exclusion of some of the data from the Skid Road and West End areas of the c i t y might have had on study findings. S i m i l a r l y the e f f e c t of the loss of cases because of d i f f i c u l t labor negotiations cannot be determined. (e) Demographic di f f e r e n c e s : Sherman (1979) has suggested that high-risk patients may choose to move into an area with paramedic services. There is no way to assess the lik e l i h o o d of such an occurrence having compromised our study. Furthermore, although i t is known that the f i r s t two paramedic units were based in areas where t h e i r acceptance by community hospitals and physicians was greatest (verbal communication: L. V e r t e s i ) , the t h i r d , in down-town Vancouver, was located there on the basis of greatest need, and this difference in population served was not controlled for during the course of t h i s study. 5 9 . (J) Instrumentation: The Information which EMAs were asked to record for the study was generally very straight-forward, and the recording of t h i s type of information would not l i k e l y change over time. Although i t would be possible to make an error in assessing an item such as presumed cause of a r r e s t , i t would frequently have been obvious i f the cause were a severe, but not heart-related, medical problem, and there would l i k e l y have been someone at the scene to provide information about the medical s i t u a t i o n for patients who had been i l l f or a while. S i m i l a r l y , i t should have been reason-ably c l e a r i f the cardiac arrest were due to overdose, drowning, or trauma. If, however, there was a question about t h i s or information about any other study variable,.and no one was a v a i l a b l e who could provide reasonably r e l i a b l e information so that the EMAs could com-plete the study sheet, the space for the information on the var i a b l e in question was l e f t blank. (g) Community awareness: Changes in community awareness of the paramedic ambulance service could constitute another threat to internal v a l i d i t y . No changes in community awareness of the ambu-lance service in general, or the paramedic service in p a r t i c u l a r , appeared to have occurred during the study period. External V a l i d i t y , Or Generalizab?1ity There are also threats to v a l i d i t y which l i m i t external v a l i d i t y , or g e n e r a l i z a b i 1 i t y . The most problematic f o r t h i s study was contam-ination by intervening v a r i a b l e s which have an e f f e c t dn outcome. 60. Such v a r i a b l e s as c l i n i c a l s e v e r i t y , c o m p l i c a t i n g f a c t o r s , o r c e r t a i n p a t i e n t c h a r a c t e r i s t i c d i f f e r e n c e s between t h e s t u d y and c o m p a r i s o n groups were not c o n t r o l l e d f o r , a l l o f w h i c h m i g h t have had an impact on outcomes. Such v a r i a b l e s as s o c i o e c o n o m i c s t a t u s , smoking h a b i t s , and o b e s i t y would be d i f f i c u l t f o r ambulance p e r s o n -nel t o r e c o r d w i t h any degree o f c o n s i s t e n c y . W ithout d e t a i l e d i n t e r v i e w s w i t h f a m i l y members o r e x a m i n a t i o n o f h o s p i t a l r e c o r d s , p r i o r m e d i c a l h i s t o r y and s e v e r i t y o f c l i n i c a l c o n d i t i o n c o u l d not be measured, and t h i s s t u d y d i d not have t h e r e s o u r c e s t o a s s e s s t h e s e v a r i a b l e s f o r p a t i e n t s i n t h e s t u d y . T h e r e f o r e i t has been assumed t h a t t h e s e v a r i a b l e s were d i s t r i b u t e d comparably t h r o u g h -out s t u d y and comparison g r o u p s . CRITERIA FOR SIGNIFICANT DIFFERENCE IN STUDY FINDINGS There a r e two g e n e r a l t y p e s o f s i g n i f i c a n c e t h a t one can d i s c u s s i n r e l a t i o n t o s t u d y f i n d i n g s . The f i r s t i s s t a t i s t i c a l s i g n i f i c a n c e , and the p r o b a b i l i t y v a l u e s a s s o c i a t e d w i t h s t a t i s t i c a l t e s t s used f o r a n a l y s i s o f s t u d y d a t a g i v e one i n f o r m a t i o n r e g a r d -ing t h e l i k e l y s t a t i s t i c a l s i g n i f i c a n c e o f d i f f e r e n c e s f ound. The second t y p e o f s i g n i f i c a n c e i s p r a c t i c a l s i g n i f i c a n c e from the p o i n t o f v i e w o f s e r v i c e i a d m i n i s t r a t o r s and p r o v i d e r s , and i s a d d i t i o n a l e v i d e n c e o f the v a l u e o f the program, o v e r and above s t a t i s t i c a l s i g n i f i c a n c e . A f t e r d i s c u s s i o n w i t h the M e d i c a l D i r e c t o r o f the Advanced L i f e Support program, i t was d e c i d e d , b e f o r e any d a t a was c o l l e c t e d , t h a t a 10 per cent d i f f e r e n c e i n 61 suryiyal outcomes between the EMA II patient group and the EMA II patient group would constitute a significant difference in practi terms. 62. CHAPTER V  FINDINGS This study was carried out to determine whether or not para-medics in British Columbia have a significant impact on survival following cardiac arrest, when compared to success rates for similar cases handled by regular ambulance personnel. The traditional justification of advanced life support pro-grams has been more patients admitted alive to hospital. However, from a health care system point of view, it is also important to know whether or not more paramedic-treated patients also survive to be discharged alive from hospital. If the good work done by advanced life support personnel in getting a higher proportion of those seriously ill patients to hospital alive does not result (for whatever reason) in significantly more such patients being discharged alive, then, as Gibson (1974b) has said, a great deal of money and effort has been spent altering where the death from the incident takes place, not the fact of the death itself. As will be described, differences were observed in survival rates between EMA II and EMA III patients. A number of supplementary analyses were undertaken with a view to ruling out some of the rival explanations which might account for the findings. RESULTS A total of 443 recent cardiac arrest cases attended by staff of the Provincial Ambulance Service were identified for the period 6 3 . from September 15, 1979 to June 1, 1980. For 7 cases (.1.6%) the type of response could not be determined with certainty, and these cases were excluded from analysis. For another 17 cases (3.8%) the cause of arrest was not reported and these cases, too, were excluded. Of the remaining 419 cases, presumed cause of arrest was trauma for 14 (3.3%), overdose for 7 (J•7%), and other causes for 40 cases (9.6%), e.g., electrocution, drowning, SIDS, etc. The remaining 358 cases were believed to be cardiac arrests related to cardiac disease. After discussion with the Medical Director of the Advanced Life Support Program it was decided to exclude cases with a "time in arrest without CPR" greater than 15 minutes, or a "time to definitive care" greater than 35 minutes, since such cases were judged to be unsalvageable. Using these criteria another 34 cases (.9-5% of the 358 cases) were excluded from analysis. The remaining 324 cases form the basis of the following analysis. Initial examination of the patient groups treated by EMA lis and EMA Ills showed no statistically significant differences between the two groups on the basis of age, sex, time of day of incident (Appendix E, Tables I, II, and III). Accordingly, the course of illness for the two patient groups as they existed was determined (Table l). Initial outcome, course while in hospital for patients who were admitted alive, and final outcome were determined for the two patient groups. There were very clearly significant positive differences between proportions of EMA II and EMA Ml patients 64. admitted alive to hospital (p. = 0 . 0 0 2 ) . The findings about differences in proportions; discharged alive from hospital, though in the expected direction, are less clear (p. = 0 . 1 0 ) . Extraneous factors which might have influenced this finding are discussed in Chapter M1. The proportions of patients dying after admission to hospital were not significantly different for the two groups. TABLE I: NUMBER AND PERCENTAGE DISTRIBUTION OF OUTCOMES FOR STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT OUTCOMES - Initial Outcome Admi tted Alive to Ward/ Special Unit Died Before Admi ss ion EMA I I PATIENTS N (%) EMA I I I PATIENTS STATISTICAL TEST 10 (11 .1 ) 65 ( 2 8 . 3 ) 80 ( 8 8 . 9 ) 165 ( 7 1 . 7 ) Corrected X = 9 -7 p.= 0 . 0 0 2 Course in Hospital for Patients Admitted Alive Died in Hospital Di scharged Alive - Final Outcome (Total Patient Group) Died At Any Time D i scharged Alive 85 ( 9 4 . 4 ) 199 ( 8 7 . 3 ) 5 ( 5 . 6 ) 29 ( 1 2 . 7 ) Corrected X = 0 . 0 0 p.= 1.0 Corrected X = 2 . 8 p.= 0 . 1 0 Next, one of the other factors which might account for the observed differences in outcomes was examined. It was found that there were differences in proportions of patients found in arrest vs. arresting during attendance in the two patient groups (Table I 65. but the direction of the difference tends to favor EMA Ms, since patients who arrest during attendance by the ambulance crew haye potential for intervention earlier in the course of the incident, which should have a favorable impact on the chance for success. TABLE II: NUMBER AND PERCENTAGE DISTRIBUTION OF PATIENTS FOUND IN ARREST AND ARRESTING DURING ATTENDANCE BY TYPE OF RESPONDING ATTENDANT PATIENT CATEGORY Found in Arrest Arrested During Attendance Total EMA I EMA It I N N 76 (8.3.5) 212 (91.0) 15 0 6 . 5 1 21 (. 9.0) 9.1 233 Corrected 32= 2.98 TOTAL 288 36 324 p.= 0.08 0 The course of illness was examined separately for found in arrest and arresting during attendance patients by type of respond-ing attendant (Appendix E, Tables IV and V). Since the found in ar-rest group is such a large proportion (88.9%) of the total patient group, they contribute substantially to the findings for the whole group, and it is not surprising, therefore, to find that for the found in arrest group, there are statistically significant differ-ences favoring the EMA Ills, in proportions of cases surviving to admission and to discharge alive ((p.= 0.001) and (p.= 0.03), respect iyely). 66. Similar differences were not found for the group of patients who arrested during attendance by ambulance personnel. As might be expected, the arrested during attendance group treated by EMA lis fared better than the found in arrest group they treated. It appears- that for the arrested during attendance patient group, rapid transport to definitive care at the hospital was useful. Cardiopulmonary Resuscitation A difference favoring EMA Ills (p.= 0.00) was found in the proportion of patients who were receiving CPR on arrival of the ambulance crew (Table III). This was to be expected, since the EMA Ms would generally be able to reach the scene ahead of the EMA Ills, and firemen or EMA Ms would have started CPR while waiting for the advanced life support crew to arrive. TABLE III: NUMBER AND PERCENTAGE DISTRIBUTION OF PATIENTS WHO WERE AND WERE NOT RECEIVING CPR ON ARRIVAL OF EMAs BY TYPE OF RESPONDING ATTENDANT** CPR ON ARRIVAL OF EMAs? CPR Being Done CPR Not Being Done Total EMA I I PAT IENTS EMA II I PAT IENTS N (*) 46 (.60.5) 30 (39.5) 187 (88.6) 24 (11.4) 76 211 2 Corrected X = 27-1 p.= 0.00 TOTAL 233 54 287 ** Note: CPR/Bystander CPR only applies to cases where the patient was found in arrest, and not to cases where the patient arrested during attendance of ambulance personnel. 6 7 . The number of patients in each of the two groups who received bystander CPR before arrival of the ambulance crew was also examined (Table IV). TABLE IV: NUMBER AND PERCENTAGE DISTRIBUTION OF FOUND IN  ARREST PATIENTS WHO RECEIVED OR DID NOT RECEIVE BYSTANDER CPR BY TYPE OF RESPONDING ATTENDANT BYSTANDER CPR DONE? Received Bystander CPR Did Not Receive Bystander CPR Total EMA I I PATIENTS EMA III PATIENTS a (%) N tl) 16 (21.1) 26 02.3) 60 ( 7 8 . 9 ) 186 ( 8 7 . 7 ) 76 212 .2 TOTAL kl lk6 288 Corrected X^ = 2.80 p.= 0.09 Relatively few instances (14.6%) of bystander CPR (defined in Chapter I) were observed during this study. Generally CPR, if it was done, was performed by emergency services personnel. The pro-portions of EMA II and EMA III cases receiving bystander CPR in this study were not significantly different (p.= 0.09), though the direc-tion of the findings tends to favor survival for EMA II patients. Time In Arrest Without CPR Reports in the literature have indicated that time in arrest without CPR is extremely important for cardiac arrest victims. The present study confirms this finding (Table V). 68. TABLE V: MEDIAN TIME IN ARREST WITHOUT CPR FOR STUDY PATIENTS BY OUTCOME * OUTCOME - Initial Outcome MEDIAN (Mins.) Admitted Alive to Ward/Special Unit Died Before Admission STATISTICAL TEST Mood Median X2= 15-2 p.= 0.00 Course in Hospital for Patients Admitted Alive Died in Hospital D i scharged Alive - Final Outcome (Total Patient Group) Died At Any Time Discharged Alive Mood Median X = 2.1 p.= 0.15 Mood Median X = 6.2 p.= 0.01 Patients who were admitted alive had significantly shorter times in arrest without CPR when compared to those who died before admission (p.- 0.00), and patients who were discharged alive from hospital had shorter times in arrest without CPR than did patients who died while in the study (p.= 0.01). There was no difference in time in arrest without CPR for study patients (p.= 0.43) depending on which group of ambulance personnel ultimately provided their treatment (Table VI). Note: For analysis of observed differences in variables measured in units of time, where information on the variable was missing the case was excluded from analysis of the time^ related variable (n - 41). There appeared to be substan-tial skew in the mean times calculated, even when the data were log-transformed (Appendix E, Tables VI, VII). There-fore the conservative Mood median test, rather than a t-test was used to test for significant differences between all time variables analyzed. 69. TABLE VI: MEDIAN TIME IN ARREST WITHOUT CPR FOR STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT TYPE OF RESPONDING ATTENDANT MEDIAN TIME fN MINUTES STATISTICAL TEST EMA I I Patients EMA II I Patients 4.8 4.9 Wood Median X = 0.61 p.= 0.43 Again, this is not surprising in view of the fact that often Fire Department personnel reached Both groups of patients ahead of ambulance service personnel and began CPR, and when EMA lis were dispatched simultaneously with EMA Ills, they would generally reach the scene and take over performance of CPR for the patient while waiting for EMA Ills to arrive. Since no difference was found in proportions of EMA II and EMA III cases where bystanders initiated CPR before any ambulance arrived, then it is reasonable to find that there were no differences in time in arrest without CPR for the two patient groups. Receiving Hospital Three hundred nine patients were transported to hospital. Of the 12 hospitals receiving cardiac arrest victims from the ambulance service during the study, six had coronary care units and emergency departments which were open 24 hours a day with a physician in the department or on call within the hospital. This group of six hospitals receive 85 per cent of the patients going to hospital. Hospitals without coronary care units received the rest. Analysis of this information by type of responding attendant 70. (Table VII) shows that a significantly higher proportion of EMA III patients were taken to hospitals with coronary care units (CCUs), whatever that might mean in terms of commitment to coronary care or in terms of skills of hospital staff generally. TABLE VII: NUMBER AND PERCENTAGE DISTRIBUTION OF PATIENTS  RECEIVED BY HOSPITALS WITH AND WITHOUT CORONARY CARE UNITS BY TYPE OF RESPONDING ATTENDANT HOSPITAL HAS CCU? EMA II PAT 1ENTS EMA 111 PAT 1ENTS TOTAL N (.%) N tl) H CD Received by Hospital With CCU 45 (50.0) 217 (99.1) 262 (84.8) Received by Hospital Without CCU 45 C50.0) 2 ( 0.9) 47 (15.2) Total 90 219 309 Corrected X2= 115.4 p.= 0.00 Outcomes for patients taken to the two types of hospitals were then analyzed (Appendix E, Table VIII). No significant differences were found in proportions of patients admitted, dying in hospital, or discharged alive. That is, whether or not the receiving hospital had a coronary care unit did not appear to have had an impact on the course of illness for cardiac arrest patients delivered to these hospitals by the ambulance service. Time To Definitive Care By definition (see Chapter I) time to definitive care is generally substantially shorter for EMA il l patients than for 71 EMA II patients. This was, indeed, found to be so for patients in this study (Appendix E, Table IX\. Outcomes were then related to median time to definitive care for study patients (Table VI 1 1 ) . TABLE VIII: MEDIAN TIME TO DEFINITIVE CARE FOR STUDY PATIENTS BY OUTCOME OUTCOME - Initial Outcome Admitted Alive to Ward/Special Unit Died Before Admission MEDIAN (Mins.) STATISTICAL TEST Mood Median X = 1 0 . 3 p.= 0 .001 Course in Hospital for Patients Admitted Alive Died in Hospital Discharged Alive - Final Outcome (Total Patient Group) Died At Any Time Discharged Alive Mood Median X = 0.81 p.= 0 . 3 7 Mood Median X = 4 . 6 p.= 0 . 0 3 Time to definitive care proved to be significant for patients who were admited alive compared to those who died before admission (p.= 0 .001 ) and for those who were eventually discharged alive compared to those who died at any time (p.= 0 . 0 3 ) . Length of Hospitalization One of the arguments against having paramedics is that this may lead to a large number of people who will certainly die while 7 2 . in hospital being admitted alive and using vast quantities of scarce resources before their eventual demise. One measure of resource utilization is the number of days spent in hospital. Analysis was done for patients in this study who were discharged alive, or who died while in hospital, to see if there were significant differences in lengths of hospitalization for those who had been treated by paramedics compared to those who were treated by EMA Ms (Appendix E, Tables X and XI). A longer median length of hospitalization was observed for EMA III patients discharged alive than for EMA II patients discharged alive, but this did not proved to be statistically significant (p.= 0 . 5 9 ) . EMA III patients who died in hospital had a longer median length of hospitalization than did EMA II patients who died in hospital, but the difference was not significant (p.= 0 . 1 1 ) . Because EMA III patients dying in hospital had a longer median length of hospitalization than did the similar EMA II group, length of hospitalization was examined for all those in the group of patients who died while in hospital. The median length of stay for this group proved to be 2.1 days. Therefore, even if the observed difference between EMA M and EMA III patients had proved to be statistically significant, the difference in total number of days in hospital would not have been significant in practical terms since the length of stay was so short. Surv ivors The patients who survived their cardiac arrest and were 73-eventually discharged alive from hospital were examined as a group. As was expected, a higher proportion of patients under 50 years of age survived, and a smaller proportion of those 70 or older survived. The mean age of survivors was 61.6. Seventy-nine per cent of survivors were found in arrest, a smaller percentage than the 88.9 per cent for the study group as a whole. The greater potential for successful outcomes for patients arresting during attendance of ambulance personnel has been noted earlier in the chapter. Seventy-four per cent of survivors were male, and 65 per cent had the ambulance called for them during the day, rather than at night. Neither of these findings is particularly different from the findings for the study group as a whole. 74. CHAPTER VI  DISCUSSION AND CONCLUStONS RESEARCH QUESTION 1 Are there significant differences in the proportions of patients surviving to hospital admission between the group of patients treated by EMA lis only, and that treated by EMA Ills only, or a combination of EMA Ills and EMA I Is? Data from this study indicate that there are, indeed, survival differences between patients treated by EMA Ms and those treated by EMA Ills or a combination of types of personnel, on this initial outcome measure (p.= 0.002). Furthermore, these differences are significant in practical terms when the standard is a ten per cent difference in survival rates between the two patient groups as established before data collection began. The initial outcome survival rate for EMA II patients was 11.1 per cent, compared to 28.3 per cent for paramedic patients; i.e., the rate for EMA III patients was more than double that for EMA I I pat ients. In the review of studies dealing with outcomes for cardiac arrest patients, only the study by Eisenberg et. al. (1979c) seemed to deal with a similar patient group (Eisenberg et al., 1980b). There the initial outcome rate for patients treated by non-paramedic technicians was 17-0 per cent, and for those treated by paramedics, 39-0 per cent. Other studies in that review dealt with a subset of the population studied here (e.g., 75. patients with ventricular f ibri l lation, o r patients with myocardia1 infarctions). They report initial survival rates for paramedic patients o f from 34 per cent Cventricular fibrillation patients) t o 65 per cent Cacute myocardial infarction patients). I t i s important, however, when evaluating the relevance o f such findings, t o remember the warning about differences i n outcome rates which may be related t o unreported differences i n key variables associated with t h e particular population being studied. Such things a s whether o r not the arrest was witnessed, more rapid r e -sponse time than elsewhere, more rapid initiation o f CPR, etc., a l l have important implications for initial resuscitation rates. Many studies do not address these variables i n their reports, and thus i t i s difficult t o know w h e t h e r o r not B r i t i s h C o l u m b i a ' s advanced life support personnel should be evaluated against standards based on such findings i n t h e literature. S i n c e , however, the traditional justification for having paramedic programs i s higher initial survival rates for seriously i l l patients, this study indicates that when cardiac arrest victims are studied, B . C . ' s paramedic program appears t o be justified both i n statistically and i n practically significant terms. In S e a t t l e , C o b b , B a u , A l v a r e z , and S c h a f f e r 0975) documented an improved survival rate for paramedic patients o f from 34 per cent t o 43 per cent, and a survival t o discharge improvement from 11 per cent t o 23 per cent during a second time period compared t o an initial time period. I t would be interesting t o examine results for Provincial Ambulance Service personnel in British Columbia now that they have still greater experience in dealing with cardiac arrest victims, and, as well, many more people in the community have received training in cardiopulmonary resusciation. The patient groups treated by EMA Ms and EMA Ills appeared to be similar with respect to age, sex, and time of day of call. There were differences with respect to percentage of patients found in arrest and arresting during attendance of ambulance personnel (p.= 0.08), and incidence of bystander CPR (p.= 0.09), though the direction of these last two differences tends to favor better outcomes for EMA II patients. This adds weight to study findings of significantly better initial outcomes for paramedic patients. Two differences between the patient groups were as would be expected: more EMA III patients had CPR before arrival of the paramedics since other emergency services personnel were dispatched at virtually the same time and could generally reach the scene faster to begin CPR; and more EMA III patients were taken to hospital which had CCUs (these were the hospitals near the ambulance stations at which the paramedics were based, and often had been involved in providing training to or refresher courses for paramedics). When, because of such findings, time in arrest without CPR for EMA II patients was compared to time in arrest without CPR for EMA III patients, the differences were not statistically significant. When outcomes were examined for the 77. patient groups delivered to hospitals with and without CCDs, no statistically significant differences were found. Thus,, these differences would not likely explain the observed differences for EMA II and EMA III patients on the initial survival measure. Analysis was done separately for the found in arrest group of patients by type of responding attendant, and for the patient group arresting during attendance by type of responding attendant. When initial outcome was examined for the found in arrest group, a statistically significant difference was observed in initial outcome (p.= 0.001), with paramedic patients doing better (26.3 per cent surviving to admission, vs. 7.9 per cent for the EMA II patient group). This also meets the criterion for significant difference in practical terms. This difference on the initial survival outcome did not appear for the group of patients who arrested during attendance by ambulance personnel, indicating that for this patient group at least, EMA Ms who can transport patients rapidly to definitive care at local hospitals may provide a useful service. Since, however, there can be no service control over the likelihood of the patients' arresting during attendance of ambulance staff, rather than arresting before they arrive, this finding has few service planning implications. Mention should perhaps be made of the fact that a widespread public education campaign which was aimed at informing people of the signs and symptoms of heart attacks, of whom to call for help when such an incident occurs, and of the need for lay people to be trained to provide CPR, 78. might result in ambulances being called earlier for heart attack victims which would tend to gtve patients greater chances of successful outcomes from such incidents. It may well, however, also result in more inappropriate calls tying up ambulances which would better be sent to other emergencies! Significant differences were found between EMA II and EMA III patient groups on the basis of time to definitive care, but as was pointed out in Chapter V, this is so almost by definition. RESEARCH QUESTION 2 Are there significant differences in the proportions of patients discharged alive from hospital between the group treated by EMA Ms only and the group treated by EMA Ills only or a combination of Mis and Ms? Data from this study indicate that there are only marginally significant differences between EMA II patients and EMA Ml patients on this final outcome measure (p.= 0.10). Though the observed differences (5-6 per cent of total EMA II treated group discharged alive and 12.7 per cent of total EMA III treated group discharged alive) do not meet the criterion of a 10 per cent difference in outcome for practical significance, twice as many paramedic patients were discharged alive from hospital as EMA II patients. Paramedic performance in this study was similar to that observed in three of the five studies critiqued in some detail in Chapter II in terms of percentage of total paramedic patient group discharged alive from hospital: Diamond, Schofferman, and Elliot (.1977) —13 per cent; Lauterbach, Spadafora, and Levy 79. (J 978) — 1 5 pe r c e n t ; L i b e r t h s o n , N a g e l , H i r s c h m a n , and N u s s e n f e l d (J974)--l4 p e r c e n t . I t i s a l s o s i m i l a r t o r e s u l t s f r om t h e f i r s t two y e a r s o f t he s t u d y by C o b b , Baum, A l v a r e z , and S c h a f f e r (1975)— 11 pe r c e n t , though lower t h a n t h e i r 23 pe r c e n t s u c c e s s r a t e f o r t he second t w o - y e a r p e r i o d , and lower t han t h e (17%/24%/l3%) r a t e s f rom t h e s t u d y by E i s e n b e r g , B e r g n e r , and H a l l s t r o m (1980a). When f i n a l outcome was d e t e r m i n e d f o r f ound i n a r r e s t and a r r e s t i n g d u r i n g a t t e n d a n c e p a t i e n t s by t y p e o f r e s p o n d i n g a t t e n d a n t (Append i x E , T a b l e s IV and V ) , s i g n i f i c a n t d i f f e r e n c e s in f i n a l outcome f a v o r i n g t he EMA II I g roup were found f o r t h o s e found i n a r r e s t (p.= 0.03), but not f o r t h o s e a r r e s t i n g d u r i n g a t t e n d a n c e '(p.= 1.0). The number o f p a t i e n t s i n t h i s s t u d y who were d i s c h a r g e d a l i v e i s s m a l l , and r e s u l t s may have been c o l o r e d by such t h i n g s as EMA II e r r o r i n not r e c o g n i z i n g s e r i o u s rhythm d i s t u r b a n c e s i n p a t i e n t s who s u b s e q u e n t l y a r r e s t , and o t h e r i m p o r t a n t d i f f e r e n c e s w h i c h were not a d d r e s s e d i n t h i s s t u d y ; f o r e x a m p l e , m o r b i d i t y d i f f e r e n c e s r e s u l t i n g f rom a g g r e s s i v e i n t e r v e n t i o n by emergency r e s p o n s e p e r s o n n e l : damage done w h i l e a d m i n i s t e r i n g CPR, a d m i n i s t r a -t i o n o f oxygen t o p a t i e n t s i n s u c h a f a s h i o n t h a t f u r t h e r p r o b l e m s d e v e l o p , e t c . (Agdal & J o r g e n s e n , 1973 ; A t c h e s o n £ F r e d , 1975; C a r o l i n e , 1975; Jeong £ Caccamo, 1975; M c l n t y r e , P a r i s i , B e n f a r i , e t a l . , 1977; P a t t e r s o n , B u r n s , £ J a n n o t t a , 1973; S t e w a r t , 1977). No measurement was made o f whe the r o r no t a more s e r i o u s l y i l l g roup o f p a t i e n t s was d e l i v e r e d a l i v e t o t he h o s p i t a l by EMA I l l s . 8 0 . No assessment of hospital differences beyond availability of a coronary care unit and an emergency department which was open 2k hours a day was undertaken, and, clearly, other hospital differences could well have an impact on final outcomes for cardiac arrest patients. It is obvious that a number of intervening variables which might have a role to play in how likely it is that a giyen patient will be discharged alive from hospital after a cardiac arrest have little or nothing to do with how well the ambulance personnel complete their treatment of cardiac arrest victims, but do have an impact on final outcome -measures. If the question is, "Do EMA Ills save a higher proportion of the cardiac arrest victims whom they treat than do EMA Ms?", then the answer appears to be "yes", particularly for those patients (the vast majority) who are found in arrest. OTHER VARIABLES EXAMINED Time in Arrest Without CPR Although no significant differences were found in median time in arrest without CPR for EMA II and EMA III patients, this time in arrest without CPR did prove to be very significantly different between those who lived and those who died, both initially at admission to hospital (p.= 0 . 0 0 ) and at discharge alive (p.= 0 . 0 1 ) . Given this finding, there are a number of ways to attack the problem of reducing time in arrest without CPR. One is to reduce the time it takes emergency response personnel from whichever service, Fire Department, Police Department, or Provincial Ambulance Service, to 81. reach the scene and to begin CPR. A far less costly alternative might be to teach more lay people how to perform CPR and how import-ant it is that this be started quickly when a cardiac arrest occurs. Cobb et al. (1976) reported that the cost of such education courses at that time was a total of $1.25 (U.S.) for each student, though courses in CPR offered in Vancouver to the general public in recent years have charged from $15 to $20 per student. If this is, indeed, an accurate estimate of the real costs of teaching citizen CPR, then perhaps such courses would be better targeted at relatives of those at high risk for heart attacks. Cost, however, in this case need not be a matter of prime concern for planners except insofar as cost reduces the numbers of people willing to take training, since fees are paid by those enrolling in the course, rather than from the public purse. Another issue arises when the importance of availability of bystander CPR is discussed. Pantridge and Adgey as early as 1969 noted that without regular practice,' ability to perform effective CPR deteriorates rapidly after the completion of training. Some, however, believe that the critical thing is early initiation of CPR by bystanders before arrival of emergency response personnel, regardless of how well or how poorly it is performed (verbal communication: L. Vertesi, 1982). Time To Definitive Care Time to definitive care was, by definition, different for paramedic and non-paramedic patient groups. However it is only 82. when impact of time to definitive care on outcomes is examined that the substantial difference quite small amounts of time make becomes apparent. From Table VIII in Chapter V it can be seen that the difference in median times between those who were admits ted alive and those who died before admission was 2.4 minutes. A difference of 2.6 minutes was observed for those dying at any time compared to those discharged alive from hospital. A shortcoming of this particular study is that the time variable is taken from when the call is received by the dispatch office, rather than from when the incident occurs, and what is important for the patient is the time lapse between when the in-cident occurs and the time he receives definitive care for the problem. For other evaluations of the Provincial Ambulance Service it will be important to devise a method for more accurate determina-tion of time from onset of symptoms to time at which the intervention of interest takes place. If a more accurate measure of time from onset to various key interventions can be achieved, then more use-ful findings can be generated and analyzed: The lack of discriminating time measurement could par-tially explain the wide variation in reported discharge rates: 6% to 24%....Presenting a summary discharge rate obscures the importance of times. By stratifying time and measuring outcome, the critical relationship between time and outcome emerges. (Eisenberg et al., 1979a, p. 1907) Although it appears that a short time to initiation of CPR does buy time for the patient, it has to be coupled with a relatively short time to definitive care if the patient is to survive. Neither factor alone is sufficient. 8 3 . A few options exist for reducing time to d e f i n i t i v e care for patients. Increasing the number of ambulances a v a i l a b l e to rush cardiac arrest victims to the hospital would tend to reduce the time to d e f i n i t i v e care for EMA M patients, but at a high cost to the taxpayer. The option of increasing the number of paramedic vehicles so that paramedics can provide d e f i n i t i v e care to a higher proportion of the cardiac arrest victims who need i t is a s t i l l more costly one. Furthermore, t h i s l a t t e r action would tend to reduce the number of such c a l l s handled by each paramedic, and i t has been suggested that t h i s would result in d e t e r i o r a t i o n of the s k i l l s necessary to intervene successfully in cardiac arrest events (Bergner et a l . , 1 9 8 1 ) . Where local conditions do not permit establishment of a para-medic service, improved outcomes for cardiac arrest patients might be achieved by having regular ambulance personnel trained to recognize the circumstances under which d e f i b r i l l a t i o n is appropriate and in such circumstances, administer i t (Eisenberg, Copass, Hallstrom, Blake, et a l . , 1 9 8 0 c ) . For this to be a v i a b l e a l t e r n a -t i v e , however, a r e l a t i v e l y short time from patient collapse to a r r i v a l of the d e f i b r i 1-lator-trained ambulance personnel is essent i a l . Witnessed Arrests In order to shorten c r i t i c a l time periods, i t is important to *** Refer to Appendix A, Part 2 for an estimate of the cost of running a single EMA II and a single EMA III vehic l e in the Lower Mainland of B r i t i s h Columbia for one year. i 8k. have the collapse either witnessed or heard. In this study, although an attempt was made to collect information about whether or not a collapse had been witnessed, the information was not recorded with any regularity. Any further research on this subject should involve stressing to participants that this is a particularly useful variable for interpreting results, and should be recorded regularly and accurately. Course While in Hospital for Those Admitted Alive It is interesting to find that the course while in hospital never proved to be significantly different, whatever the two groups compared. For each pairing of groups, roughly the same proportion of patients died in hospital and were discharged alive. Since this study did not attempt to assess variables such as severity of illness of patients, or prior medical history, it is impossible to know whether or not the paramedic patients admitted to hospital were generally more seriously i l l than EMA II patients admitted alive. However it seems reasonable to assume either that the two groups were equally i l l , or that the paramedics were able to deliver a more seriously i l l group of patients alive to the hospital. If the two patient groups were equally i l l , then the finding of similar courses of illness while in hospital is as expected. If, however, the EMA III patients were more seriously i l l , then it appears that in spite of this, once they were admitted to a ward or special unit they had about the same chance of being discharged alive as did patients from a less i l l group. 8 5 . Length of Hospitalization Although the median length of hospitalization for EMA III patients discharged alive from hospital was approximately five days longer than for EMA II patients discharged alive, this difference did not prove to be significant (p.= 0 . 5 9 ) . Paramedic patients who eventually died in hospital did live longer than similar EMA II patients, but the differences were small, as discussed earlier. In this study paramedics did not transport patients to hospital who lived long enough to use substantia11y more resources before they died than did EMA II patients who died in hospital. For the study group as a whole, patients who were discharged alive spent significantly longer in hospital (p.= 0 . 0 0 ) than did those who died in hospital (Appendix E, Table Xll), but this is as expected. The median length of hospitalization for patients eventually discharged alive from hospital after an out-of-hospital cardiac arrest was 1 6 . 0 days. CONCLUSIONS AND EVALUATION OF THE STUDY This study found significant differences, statistically and practically, in outcomes on admission to and discharge from hospital for EMA III patients who suffered an out-of-hospita1 cardiac arrest, compared to outcomes for a similar group of patients treated by EMA Ms, with a larger proportion of paramedic patients surviving. This documentation of success with a limited section of the patient population served by the advanced life support program in 86. British Columbia is only the first of a series of steps which should be taken if the program as a whole is to be evaluated. For this reason, the study provides only a limited amount of the informa-tion which is needed by program planners and administrators. Some of the shortcomings of this study have been mentioned during discussion of specific findings, but others which have not been identified are relevant: It has been impossible to assess what impact the EMA I I cases which were lost because of lack of participation by two stations and because of difficult labor negotiations would have had on study findings. Important variables such as differences in socioeconomic status and age distribution of the populations in the study and comparison areas were not measured. - Time from onset of patient symptoms until arrival of ambulance service personnel, or until definitive care was received, was not ava ilable. No assessment of level of function for patients who were discharged alive from hospital was undertaken. - While the group of paramedics participating in the study were experienced and no new paramedics joined crews during the course of the study, no measure was taken of the experience levels of the EMA Ms working in the Lower Mainland during the study. - While it is believed that virtually all cases involving potentially salvageable cardiac arrest victims which occurred in 8 7 . the Lower Mainland would be handled by personnel from the Provincial Ambulance Service, no independent assessment of the v a l i d i t y of t h i s assumption was undertaken. - The many intangible benefits discussed in the l i t e r a t u r e review section have not been measured and/or at t r i b u t e d to the paramedic program. - Only a gross estimate of the cost of operating a paramedic vehicle compared to operating an EMA II ve h i c l e has been included (.see Appendix A, Part 2).. No measurement of indirect cost has been undertaken, and no attempt has been made to apportion a ce r t a i n amount of the i d e n t i f i e d costs to provision of services to cardiac arrest victims. Both d i r e c t and ind i r e c t costs (including Opportun-i s t i t y costs associated with having an advanced l i f e support program), and d i r e c t and ind i r e c t benefits should be measured, so that compari-son of results and costs can be made. - The focus of the advanced 1ife support program has changed over time in recognition of the fact that paramedics must deal with a much broader range of lif e - t h r e a t e n i n g conditions than was f i r s t envisioned, but th i s study deals with only a small subset of the cardiac care which i t was e a r l i e r f e l t would comprise much of thei r caseload. This is an evaluation of a single small component of paramedic work today, and results must be considered in l i g h t of this f a c t . DIRECTIONS FOR FUTURE RESEARCH In order to more appropriately evaluate the paramedic program 88. in British Columbia so that the necessary information for planners and administrators is generated, a much broader, and therefore much more difficult, research project would have to be conducted. In such an evaluation project the main areas of activity for advanced life support personnel today would be identified, and an assessment made of performance in each of them. Two areas which would likely be identified for study are treat-ment of all cardiac patients, and treatment of trauma victims. Within each of these areas, patients treated could be grouped, for example, into "mild", "moderate", and "seriously i l l " categories, before comparison with similar groups of patients treated only by regular ambulance attendants was undertaken. Expected outcomes for each of the patient groups would be identified, and criteria for significant differences in outcome measures, both in statistical and in practical terms, would be established. Skill levels, or at least training and years of experience, would be measured for EMA Ms and EMA Ills participating in the study. Patients treated by EMA Ms and EMA Ills would be compared on such variables as age, sex, socio-economic status, and prior medical condition. Hospital differences should be identified so that these differences can be considered in relation to any outcome differences found for patients. Time variables which are measured should be related to the time of onset of patient symptoms, rather than to the time at which the call was received at dispatch. Measurement of level of functioning for patients leaving the hospital should be undertaken. Costs, both direct and indirect, of running both the advanced life support and 8 9 . regular ambulance programs should be Identified, so that outcomes can be assessed in relation to costs of providing a specific type of service. Clearly such a research project goes far beyond what was accomplished in this study. However, it is very encouraging that program administrators and service providers were willing to have an outsider examine the highly visible Provincial Ambulance Service for purposes of evaluation. For it is only with information from such real-life research that planners and administrators can make informed decisions about existing programs and new directions in the provision of health care services. 90. BIBLIOGRAPHY Acton, J. P. Evaluating public programs to save lives: the case  of heart attacks. Santa Monica: Rand, 1973-Adgey, A. A. J., S Geddes, J. S. Cardiac ambulance service. (Letter). Lancet, 1977, 1, 951. Agdal , N., & Jorgensen, T. G. Penetrating laceration of the peri-cardium and myocardium and myocardial rupture following closed chest cardiac massage. Acta-fledica Scandinavica, 1973, 194, 477-479. Alvarez III, H., £ Cobb, L.A. Experiences with CPR training of the general public. Proceedings of the national conference  on standards for cardiopulmonary resuscitation and emergency  cardiac care, May 1973. American Heart Association, 1975. Alvarez III, H., Miller, R. H., £ Cobb, L. A. Medic I: the Seattle advanced paramedic training program. Proceedings  of the national conference on standards for cardiopulmonary  resuscitation and emergency cardiac care, May 1973. American Heart Association, 1975. Anderson, G. L., Knobel, S. B., £ Fisch, C. Continuous pre-hospital monitoring of cardiac rhythm. American Heart  Journal, 1971, 8 2 , 642-646. Anderson, L., £ El rod, J. Rate of pick-up/response time mortality study. In H. Z. McLaughlin (Ed.), Proceedings from the  national conference on emergency medical outcome measurement  research. Atlantic Beach, 1975. Aronow, D. B. Evaluating prehospital emergency cardiac care. Letter to the editor. Annals of Emergency Medicine, 1981, J_0, 120-121. Aronow, W. S., £ Stemmer, E. A. Two year follow-up of angina pectoris: medical or surgical therapy. Annals of Internal  Medicine, 1975, 82, 208-212. Atcheson, S. G., £ Fred, H. L. Complications of cardiac resuscita-tion. Letter to the Editor. American Heart Journal, 1975, 89, 263-265. Attkisson, C. C, £ Hargreaves, W. A. A conceptual model for program evaluation in health organizations. In H. C. SchuN berg £ F. Baker (Eds.), Program evaluation in the health fields. New York: Human Sciences Press, 1979. 91. Barber, J. M., Boyle, D. M., Walsh, M. F., et al. Delay times in acute ischaemic heart disease. British Heart Journal, 1973. 35, 861-862. Barstow, J. A second look at cost control. Dimensions, 1982, 59, 15-16. Baum, R. S., Alvarez III, H., Cobb, L. A. Survival after resuscita-tion from out-of-hospita1 ventricular fibrillation. Circulation, 1974, 50, 1231-1235. Bergner, L., Eisenberg, M., Hallstrom, A., Becker, L. Eva 1uation  of paramedic services for cardiac arrest (DHHS Publication No. (PHS) 82-3310). U.S. Department of Health and Human Serv i ces, 1981. Binn ion, P. F. , Makous, N., £ Keller, W. W. Cost of a mobile coronary care unit. (Letter). American Heart Journal, 1972, 83, 723-724. Binnion P. F. , Mandal, S., & Makous, N. The mobile coronary care unit. (Letter). Journal of the American Medical Association, 1973, 223, 923. Braunwald, E. Letter to the Editor. New England Journal of  Medicine, 1977, 297, 1469-1470. Briggs, R. S., Brown, P. M., Crabb, M. E., et al. The Brighton resuscitation ambulances: a continuing experiment in prehospital care by ambulance staff. British Medical Journal, 1976, 2, 1161-1165. British Columbia. Emergency Health Services Act. S.B.C. 1974, c. 30. British Columbia. Medical Practitioners Act. R.S.B.C. 1979, c. 254, Sec. 93(2). British Columbia. Ministry of Municipal Affairs. Stat i sties  relating to regional and municipal governments in British  Columbia, June 1981. Victoria: Queen's Printer, 1981. Cain, G. G.,& Hollister, R. G. The methodology of evaluating social action programs. In P. H. Rossi & W. Walter (Eds.), Eva 1uat i ng  social programs. Theory, practice, and politics. New York: Seminar Press, 1972. Caroline, N. L. Emergency care in the streets. Boston: Little, Brown and Company, 1979-92. Cobb, L. A., Alvarez, H., £ Copass, M. K. A rapid response system for out-of-hospital cardiac emergencies. Medical Clinics of  North America, 1976, 60, 283-290. Cobb, L.A., Baum, R. S., Alvarez, H., £ Schaffer, W. A. Resuscita-tion from out-of-hospital ventricular fibrillation: 4 years follow-up. Circulation (Supp. II I), 1975, 51 £ 52, 223-228. Cobb, L. A., Werner, J. A., £ Trobaugh, G. B. Sudden cardiac death I. A decade's experience with out-of-hospital resuscitation. Modern Concepts of Cardiovascular Disease, 1980, 49, 31 -36. Colling, A., Dellipiani, A. W., Donaldson, R. J., £ MacCormack, P. Teeside coronary survey: an epidemiological study of acute attacks of myocardial infarction. British Medical Journal, 1976, 2, 1169-1172. Cooper, J. K. , Steel, K. , £ Christoudoulou, J. P. Mobile coronary care--a controversial innovation. New England Journal of  Medicine, 1 969, 28]_, 906-907. Cooper, R. , Stamler, J., Dyer, A., £ Garside, D. The decline in mortality from coronary heart disease, USA 1968-1975. Journa1  of Chronic Diseases, 1978, 3J_, 709-720. Copley, D. P., Mantle, J. A., Rogers, W. J., et al. Improved out-come for prehospital cardiopulmonary collapse with resuscita-tion by bystanders. Ci rculation, 1977, 56, 901-905-Crampton, R. S. , Aldrich, R. F., £ Gascho, J. A. Treatment of acute myocardial infarction. (.Letter). Lancet, 1974, J_, 1106. Crampton, R. S., Aldrich, R. F., Gascho, J. A., Miles, J. R., £ StiHerman, R. Reduction of prehospital ambulance and community coronary death rates by the community-wide emergency cardiac care system. American Journal of Medicine, 1975, 5_8., 151-165. Crampton, R. S., Aldrich, R. F., Stillerman, R., et al. Reduction of community mortality from coronary artery disease after initiation of prehospital cardiopulmonary resuscitation and emergency cardiac care. National conference on standards for  cardiopulmonary resuscitation and emergency cardiac care, Dallas, 1975. Crampton, R. S., Michaelson, S. P., Aldrich, R. F., £ Gascho, J. A. Mobile coronary care. (.Letter). Lancet, 1974, 2_, 101. Crampton, R. S., Miles, J. R., Jr., Gascho, J. A., et al. Amelioration of prehospital and ambulance death fates from coronary artery disease by prehospital emergency cardiac care. Journal of the American College of Emergency Physicians, 1975, 4, 19-23. 9 3 . C r e t i n , S . M o d e l l i n g t he impact o f t r e a t m e n t s t r a t e g i e s on d e a t h f rom m y o c a r d i a l i n f a r c t i o n . In T . R. W i l l e m a i n & R. C . L a r s o n ( E d s . } , Emergency m e d i c a1 s y s t e m s a n a l y s i s . P a p e r s on t h e  p l a n n i n g and e v a l u a t i o n o f s e r v i c e s . V o l . IV. Urban p u B l i c  s a f e t y s y s t e m s . T o r o n t o : L e x i n g t o n B o o k s , 1977. C r e t i n , S . , & W i l l e m a i n , T . R. A model o f p r e h o s p i t a l d e a t h f r om v e n t r i c u l a r f i b r i l l a t i o n f o l l o w i n g m y o c a r d i a l i n f a r c t i o n . H e a l t h S e r v i c e s R e s e a r c h , 1 9 7 9 , L 4 , 2 2 1 - 2 3 4 . D a l e n , J . E. P r e - h o s p i t a l c o r o n a r y c a r e . E d i t o r i a l . A m e r l e a n  J o u r n a l o f P u b l i c H e a l t h , 1 9 7 7 , 6 7 , 5 1 2 - 5 1 4 . Del 1 I p i a n ? , A . W . , C o l l i n g , W. A . , D o n a l d s o n , R. J . , 6 McCormack , P . T e e s i d e c o r o n a r y s u r v e y — f a t a 1 i t y and c o m p a r a t i v e s e v e r i t y o f p a t i e n t s t r e a t e d a t home, i n t he h o s p i t a l w a r d , and i n t he c o r o n a r y c a r e u n i t a f t e r m y o c a r d i a l i n f a r c t i o n . B r i t i s h Hea r t  J o u r n a l , 1 9 7 7 , 3 9 , 1 1 7 2 - 1 1 7 8 . Dewar , H. A . , M c C o l l u m , J . P . K. , £ F l o y d , M. A y e a r ' s e x p e r i e n c e w i t h a m o b i l e c o r o n a r y r e s u s c i t a t i o n u n i t . B r i t i s h M e d i c a l  J o u r n a l , 1969 , k_, 2 2 6 . D iamond , N. J . , S c h o f f e r m a n , J . , S E l i o t t , J . W. F a c t o r s i n s u c c e s s f u l r e s u s c i t a t i o n by p a r a m e d i c s . J o u r n a l o f t h e  A m e r i c a n C o l l e g e o f Emergency P h y s i c i a n s , 1 9 7 7 , 6, 4 2 - 4 6 . D o n a b e d i a n , A . E v a l u a t i n g t h e q u a l i t y o f m e d i c a l c a r e . M i l b a n k Memor i a l Fund Q u a r t e r l y , 1 9 6 6 , P a r t 2, 166-203-E a r n e s t , M. P . , Y a r n e l 1 , P . P . , M e r r i l l , S . L . , & Knapp , G. L . Long te rm s u r v i v a l and n e u r o l o g i c s t a t u s a f t e r r e s u s c i t a t i o n f rom o u t - o f - h o s p i t a 1 c a r d i a c a r r e s t . N e u r o l o g y , 1 9 8 0 , 3 0 , 1 2 9 8 - 1 3 0 9 . E d i t o r i a l . Why t h e a m e r i c a n d e c l i n e i n c o r o n a r y h e a r t - d i s e a s e ? L a n c e t , 1 9 8 0 , J_ , 1 8 3 - 1 8 4 . E i s e n b e r g , M. A . , 6 B e r g n e r , L. P a r a m e d i c p rograms and c a r d i a c m o r t a l i t y : d e s c r i p t i o n o f a c o n t r o l l e d e x p e r i m e n t . P u b l i c  H e a l t h R e p o r t s , 1 9 7 9 , 9_4, 8 0 - 8 4 . E i s e n b e r g , M. S . , B e r g n e r , L . , & H a l l s t r o m , A . C a r d i a c r e s u s c i t a t i o n i n t h e commun i t y . Impor tance o f r a p i d p r o v i s i o n and i m p l i c a t i o n s f o r p rog ram p l a n n i n g . J o u r n a l o f t h e A m e r i c a n M e d i c a l A s s o c i a -t i o n , 1 9 7 9 , 24j_, 1 9 0 5 - 1 9 0 7 . (a). ~ E i s e n b e r g , M . S . , B e r g n e r , L . , H a l l s t r o m , A . E p i d e m i o l o g y o f c a r d i a c a r r e s t and r e s u s c i t a t i o n i n a s u r u r b a n commun i t y . J o u r n a l o f  t h e A m e r i c a n C o l l e g e o f Emergency P h y s i c i a n s , 1979 , 8_, 2 - 5 - Cb) 94. Eisenberg, M. S., Bergner, L., & Hallstrom, A. Out-of-hospital cardiac arrest: improved survival with paramedic services. Lancet, 1980, J_, 812-815. Ca) Eisenberg, M. S., Bergner, L., & Hallstrom, A. Paramedic programs and out-of-hospital cardiac arrest: I. factors associated with successful resuscitation. American Journal of Public  Health, 1979, 69, 30-38. Cc) Eisenberg, M. S., Bergner, L., £ Hallstrom, A. Paramedic programs and out-of-hospital cardiac arrest: II. Impact on community mortality. American Journal of Public Health, 1979, 69, 39-42. (d) Eisenberg, M. S., Bergner, L. , Hallstrom, A., £ Pierce, J. Evaluation of paramedic programs using outcomes of prehospital resuscitation for cardiac arrest. Journal of the American  College of" Emergency Physicians, 1979, 8_, 458-461 . fe] Eisenberg, M. S., Bergner, L., £ Hearne, T. Out-of-hospital cardiac arrest: a review of maj'or studies and a proposed uniform reporting system. American Journal of Public Health, 1980, 70, 236-240. (b) Eisenberg, M. S., Copass, M. K., Hallstrom, A. P., Blake, B. et al. Treatment of out-of-hospital cardiac arrests with rapid defibrillation by emergency medical technicians. New England  Journal of Medicine, 198O, 302, 1379-1383. Cc) Eisenberg, M. S., Copass, M. K. , Hallstrom, A., Cobb, L. A., Bergner, L. Management of out-of-hospital cardiac arrest. Failure of basic emergency medica1 technician services. Journa1  of the American Medical Association, 1980, 243, 1049-1051. Cd) Evans, R. G. Beyond the medical marketplace: expenditure, utiliza-tion and pricing of insured health care in Canada. In, S. Andreopoulos (Ed.), National health insurance: can we learn  from Canada? New York: John Wiley £ Sons, 1975. Foulkes, R. G. Health security for British Columbians. The Report of Richard G. Foulkes to the Ministry of Health, Province of British Columbia. December 1973-Geddes, J. S., Adgey, A. A. J., Webb, S. W. Mobile coronary care unit. (Letter). British Medical Journal, 1972, j_, 507. Gibson, G. Emergency medical services: the research gaps. Health  Services Research, 1974, 3, 6-21. (a) 95. G i b s o n , G. E v a l u a t i v e c r i t e r i a f o r emergency ambu lance s y s t e m s . S o c i a l S c i e n c e £ M e d i c i n e , 1973, 7, 425*454. G i b s o n , G. G u i d e l i n e s f o r r e s e a r c h and e v a l u a t i o n o f emergency m e d i c a l s e r v i c e s . H e a l t h S e r v i c e s R e p o r t s , 197**, 89, 99-111. (b) G r a c e , W. J . The m o b i l e c o r o n a r y c a r e u n i t and t h e i n t e r m e d i a t e c o r o n a r y c a r e u n i t i n t h e t o t a l s ys tems a p p r o a c h t o c o r o n a r y c a r e . C h e s t , 1970, 58, 363-368. G r a c e , W. J . , & C h a d b o u r n , J . A . The f i r s t hour i n a c u t e m y o c a r d i a l i n f a r c t i o n . H e a r t L u n g , 1971*, 3, 736-7** 1. G r a c e , W. J . , & C h a d b o u r n , J . A . M o b i l e c o r o n a r y c a r e u n i t . N a t i o n a l c o n f e r e n c e on s t a n d a r d s f o r c a r d i o p u l m o n a r y r e s u s c i t a - t i o n and emergency c a r d i a c c a r e . D a l l a s , 1975. G r a f , W. S . , P o l i n , S . S . , £ P a e g a l , B. L. A communi ty p rog ram f o r emergency c a r d i a c c a r e . A t h r e e - y e a r c o r o n a r y a m b u l a n c e / p a r a m e d i c e v a l u a t i o n . J o u r n a l o f t he A m e r i c a n M e d i c a l  A s s o c i a t i o n , 1973, 226, 156-160 G r a f , W. S . , P o l i n , S . S . , & P a e g a l , B. L. Emergency c a r d i a c c a r e i n Los A n g e l e s . N a t i o n a l c o n f e r e n c e on s t a n d a r d s f o r c a r d i o - pu lmonary r e s u s c i t a t i o n and emergency c a r d i a c c a r e . D a l l a s , 1975 . G u t t e n t a g , M. , 5 S t r u e n i n g , E . L . , E d i t o r s . Handbook o f e v a l u a t i o n  r e s e a r c h . V o l . 2. B e v e r l y H i l l s : Sage P u b l i c a t i o n s , 1975. G u z y , P . M. , P e a r c e , M. L . , G r e e n f i e l d , S . e t a l . C i t i z e n c a r d i o p u l m o n a r y r e s u s c i t a t i o n d u r i n g o u t - o f - h o s p i t a l e m e r g e n -c i e s i n m e t r o p o l i t a n Los A n g e l e s . C l i n i c a 1 R e s e a r c h , 1979, 27, 79A. H a c k e t t , T . P . , & Cassem N. H. F a c t o r s c o n t r i b u t i n g t o d e l a y i n r e s p o n d i n g t o t h e s i g n s and symptoms o f a c u t e m y o c a r d i a l i n f a r c t i o n . A m e r i c a n J o u r n a l o f C a r d i o l o g y , 1969, 24, 651-658. Hampton, J . R. Impor tance o f p a t i e n t s e l e c t i o n i n e v a l u a t i n g a c a r d i a c ambu lance s e r v i c e . B r i t i s h M e d i c a l J o u r n a l , 1976, J_, 201-203. Hampton, J . R . , D o w l i n g , M . , & N i c h o l a s , C . C o m p a r i s o n o f r e s u l t s f rom a c a r d i a c ambu lance manned by m e d i c a l o r n o n - m e d i c a l p e r s o n n e l . L a n c e t , 1977, J_, 526-529-Hampton, J . T . , & N i c h o l a s , C . Randomized t r i a l o f a m o b i l e c o r o n a r y c a r e u n i t f o r emergency c a l l s . B r i t i s h M e d i c a l J o u r n a l , 1978, ]_, 1118-1121. 96. Harrison, E. E., Straub, E. J., 6 Amey, B. D. Sudden cardiac death. (Letter). British Heart Journal, 1976, 3 8 , 997~998. Hill, J. 0., Holdstock, G., S Hampton, J. R. Comparison of mortal-ity of patients with heart attacks admitted to a coronary care unit and an ordinary medical ward. British Medical Journal, 1977, 2, 8 I - 8 3 . Hoffer, E. P. Prehospital advanced life support: what color are the emperor's new clothes? Journal of the American College of  Emergency Physicians, 1979, 434-436. Houston, T. R., Jr. The behavioral sciences impact-effectiveness model. In P.H. Rossi & W. Eilliams (Eds.), Evaluating social programs; theory, practice & politics. New York: Seminar Press, 1972. Hutter, A. M., Russell, R. 0., Resnekov, L., et al. Unstable angina pectoris--nationa1 randomized study of surgical vs. medical therapy: results in 1, 2, and 3 vessel disease. C i rculat ion, 1977, 55-56, Suppl. Ill, 111-60. Ibrahim, M. A. Epidemiology—application of health services. In K. W. Peterson (Ed.), Resource book, health and behavioral  sciences. Ann Arbor, Mich.: Health Administration Press, TsW. Jeong, Y.-G., 6 Caccamo. L. P. Cardiac resuscitation and vertebral fracture. Letter to the Editor. American Medical Association  Journal , 1975, 23_4, 1223. Killip, T. Impact of coronary care on mortal ity from ischemic heart disease. In, R. J. Havlik, & M. Feinlieb, (Eds.), Proceed i ngs  of the conference on the decline in coronary heart disease  mortality. DHEW/HIH, Bethesda, 1979. Lauterbach, S. A., Spadafora, M., & Levy, R. Evaluation of cardiac arrests managed by paramedics. Journal of the American College  of Emergency Physicians, 1978, 7_, 355 _357-LeClair, M. The Canadian health care system. In, S. Andreopoulos, (Ed.) , National health insurance: can we learn from Canada? New York: John Wiley & Sons, 1975. LeMire, J. Emergency cardiac care in Canada. Editorial. Canadian Medical Association Journal, 1977, 117, 136"!. LeMire, J., & Johnson, A. L. Is cardiac resuscitation worthwhile? National conference on standards for cardiopulmonary  resuscitation and emergency cardiac care. Dallas: American Heart Association, 1975. 97. Lewis, A. J., Ailshie, G. E., & Criley, J. M. Long-term survival following prehospital resuscitation from ventricular fibril-lation. In, National confererice on standards for cardio- pulmonary resuscitation and emergency cardiac care. Dallas: American Heart Association, 1975. Lewis, A. J., S Criley, J. M. Prehospital management of acute myocardial infarction. In, R. S. Eliot, (.Ed.), Cardiac  emergencies. Mt. Kisco, N.Y.: Futura Publishing, 1977. Lewis, J. P. Effectiveness of advanced paramedics in a mobile coronary care system. Journal of the American Medical  Association, 1979, 241, 1902-1904. Liberthson, R. R. , Nagel, E. L. , Hirschman, J. C, & Nussenfeld, S., Prehospital ventricular fibrillation. Prognosis and follow-up course. New England Journal of Medicine, 1974, 291, 317-321. Lown, B. Are mobile coronary care units the answer? Editorial. Hospital Practice, 1969, k_, 256. Lown, B., & Ruberman, W. The concept of precoronary care. Modern  Concepts of Cardiovascular Disease, 1970, 3_9, 97-102. Lown, B., S Selzer, A. Controversies in cardiology. The coronary care unit. American Journal of Cardiology, 1968, 22, 597-602. Lund, I., £ Skulberg, A. Cardiopulmonary resuscitation by lay people. Lancet, 1976, 2, 702-704. Luxton, M., Peter, T. , Harper, R. , Hunt, D., & Sloman, G. Establishment of the Melbourne mobile intensive care service. Medical Journal of Australia, 1975, j_, 612-615. Mather, H. G., Morgan, D. C, & Pearson, N. G. Myocardial infarc-tion: a comparison between home and hospital care for patients. British Medical Journal, 1976, J_, 925~929-Mclntyre, K. M. Prehospital cardiac arrest and resuscitation: evaluation and alternative strategies. Journal of the  American College of Emergency Physicians" 1979, 8_, 89 _90. Mclntyre, K. M. , Parisi, A. F., Benfari, R., Goldberg, A. H. , & Dalen, J. E. Pathophysiologic syndromes of cardiac resuscita-tion. Archives of Internal Medicine, 1978, _J3_8, 1130-1133-McLaughlin, H. Z., Editor. EMS research conference. Conference  proceedings from the national conference on emergency medical  outcome measurement research. Atlantic Beach, Fla.: Jacksonville Experimental Health Delivery Systems, Inc., 1975-98. McSwain, G. R., Garrison, W. B. , £ Artz, C. P. Evaluation of resuscitation from cardiopulmonary arrest by paramedics. Annals of Emergency Medicine, 1980, 9_, 341-345. Miller, S. Experimental design and statistics. London; Methuen, 1975. Minuck, M., & Perkins, R. Long-term study of patients successfully resuscitated following cardiac arrest. Canadian Medical  Association Journal, 1969, 100, 1 126-112lT Mogielnicki, R. P., Stevenson, K. A., £ Wi1lemain, T.R. Patient and bystander response to medical emergencies. In, T. R. Willemain, £ R. C. Larson (Eds.), Emergency medical systems analysis. Papers on the planning and evaluation of services. Vol. IV. Urban public safety systems. Toronto: Lexington Books, 1977. Moss, A. J., Wynar, B., £ Goldstein, S. Delay in hospitalization during the acute coronary period. American Journal of  Cardiology, 1969, 24, 659-665. Murphy, M. L. , Hultgren, H. N., Detre, K. , et al. Treatment of chronic stable angina: a preliminary report of survival data of the randomized Veterans Administration cooperative study. New England Journal of Medicine, 1977, 297, 620-627. Myerburg, R. J. Observations and trends in survival from prehospital cardiac arrest. In, R. J. Havlik, £ M. Feinleib, (Eds.), Proceedings of the conference on the decline in coronary heart  disease mortality. DHEW/NIH, Bethesda, 1979-Nagel , E. L. Prehospital care as a cause for coronary heart disease mortality decline. In, R. J. Havlik, £ M. Feinleib, (Eds.) Proceedings of the conference on the decline in coronary heart  disease mortality. DHEW/NIH, Bethesda, 1979. Nagel, E. L. , Hirschman, J. C, Nussenfeld, S. R. , £ Rankin, D. Telemetry-medical command in coronary and other mobile emergency care systems. Journal of the American Medical  Association, 1970, 214, 332-338. Nagel, E. L., Liberthson, R. R. , Hirschman, J. C, £ Nussenfeld, S.R., Emergency care. C i rculat ion, 1975, 52 Suppl. Ill, 216-219. Orchard, T. J. Mobile coronary care. (Letter). Lancet, 1974, J_, 263-264. (a) Orchard, T. J. Mobile coronary care. (Letter). Lancet, 1974, _2, 780-781. (b) 99. O'Rourke, M. F., & Michael ides, J. Pre-hospital coronary care: review of a system in its fifth year. Medical Journal of  Australia, 1975, 1, 615-617. Outcome Measurement Panel Discussion. tn, H. Z. McLaughlin, (.Ed.), EMS research conference. Proceedings from the national  conference on emergency medical outcome measurement research. Atlantic Beach, Fla.: Jacksonville Experimental Health Delivery Systems, Inc., 1975. Pantridge, J. F. Prehospital coronary care. Editorial. British  Heart Journal , 1974, 36, 233-237. Pantridge, J. F., & Adgey, A. A. J. Pre-hospital coronary care. The mobile coronary care unit. American Journal of Cardiology, 1969, 24, 666-673. Pantridge, J. F., & Geddes, J. S. A mobile intensive-care unit in the management of myocardial infarction. Lancet, 1967, 2_, 271-273. Parkin, H. Verbal communication, summer 1978, with the physician instrumental in planning for and training the first advanced life support personnel in BrTti'sh. Columbia. Patterson, R. H., Burns, W. A., £ Jannotta, F. S. Rupture of the thoracic aorta: complications of resuscitation. Journal of the American Medical Association, 1973, 226, 197~ Pedoe, L. T. Decline in mortality from coronary heart disease in America. (Letter). Lancet, 1980, J_, 83I . Peterson, 0. L. Evaluating medical technology. Editorial. Anna 1s  of Internal Medicine, 1976, 8_5, 819-821. Pozen, M. W. On pre-hospital coronary care. American Journal of  Public Health, 1977, 67, 1107. Pozen, M. W. Pre-hospital coronary care: the current case for a paramedic strategy. (Letter). American Journal of Public  Health, 1979, 69, 13-14. Pozen, M. W., Fried, D. D. , Smith, S., et al. Studies of pre-hospital patients with ischemic heart disease. I. The outcome of pre hospital life-threatening arrhythmias in patients receiving electrocardiographic telemetry and thera-peutic interventions. American Journal of Public Hea1th, 1977, 67, 527-531• 100. Pyo, Y. H., & Wa t t s , R. W. A m o b i l e c o r o n a r y c a r e u n i t : an e v a l u a t i o n f o r i t s need.' 'AnnaIs'of I n t e r n a l M e d i c i n e , 1970, 73, 61-65. R i c h u p a n , S. The e f f e c t o f an EMS system on the p r o b a b i l i t y o f s u r v i v a l o f AMI p a t i e n t s — a mul t i v a r i a t e p r o b i t a n a l y s i s . I n , C o n f e r e n c e p r o c e e d i n g s from t h e n a t i o n a l c o n f e r e n c e on  emergency m e d i c a l s e r v i c e s outcome measurement r e s e a r c h . A t l a n t i c Beach, F l a . : J a c k s o n v i l l e E x p e r i m e n t a l H e a l t h D e l i v e r y Systems, I n c . , 1975. R i c h u p a n , S. , & An d e r s o n , L. A c u t e m y o c a r d i a l i n f a r c t i o n (AMI) m o r t a l i t y s t u d y . I n , Co n f e r e n c e p r o c e e d i n g s from the n a t i o n a l  c o n f e r e n c e on emergency m e d i c a l s e r v i c e s outcome measurement  r e s e a r c h . A t l a n t i c Beach, F l a . : J a c k s o n v i l l e E x p e r i m e n t a l H e a l t h S e l i v e r y Systems, I n c . , 1975. Rockswold, G., Sharma, B., R u i z , E., e t a l . F o l l o w - u p o f 514 c o n s e c u t i v e p a t i e n t s w i t h c a r d i o p u l m o n a r y a r r e s t o u t s i d e the h o s p i t a l . J o u r n a l o f the American C o l l e g e o f Emergency  P h y s i c i a n s , 1979, 8, 216-220. Rose, L. B., S P r e s s , E. C a r d i a c d e f i b r i l l a t i o n by ambulance a t t e n d a n t s . J o u r n a l o f t h e American M e d i c a l A s s o c i a t i o n , 1972, 219, 63. Rosenberg, H. M., & K l e b b a , A. J . Trends i n c a r d i o v a s c u l a r m o r t a l i t y w i t h a f o c u s on i s c h e m i c h e a r t d i s e a s e : U n i t e d S t a t e s , 1950-1976. I n , R. D. H a v l i k , ( E d . ) , P r o c e e d i n g s o f  t h e c o n f e r e n c e on t h e d e c l i n e i n c o r o n a r y h e a r t d i s e a s e  m o r t a l i t y . DHEW/NIH, Be t h e s d a , 1979-R o s s i , P. H., & W i l l i a m s , W. ( E d s . ) . E v a l u a t i n g s o c i a l programs. Theory, p r a c t i c e and p o l i t i c s . New York: Seminar P r e s s , 1972. R o s s i , P. H. , £ W r i g h t , S. R. E v a l u a t i o n r e s e a r c h — a n assessment o f t h e o r y , p r a c t i c e & p o l i t i c s . E v a l u a t i o n Q u a r t e r l y , 1977, I , 5-51. Rutman, L. ( E d . ) . E v a l u a t i o n r e s e a r c h methods: a b a s i c g u i d e . London: Sage P u b l i c a t i o n s , 1977. S a n d l e r , G. M o b i l e c o r o n a r y c a r e . Royal S o c i e t y o f H e a l t h J o u r n a l , 1973, 93> 89-91. S c a l a n , L. Rushing r o u l e t t e : t h e s t a t e o f Canada's ambulance s e r y i c e s . Canadian F a m i l y P h y s i c i a n , 1976, 22_, 61-77 S c h a f f e r , W. A., & Cobb, L. A. R e c u r r e n t v e n t r i c u l a r f i b r i l l a t i o n and modes o f d e a t h i n s u r v i v o r s o f o u t - o f - h o s p i t a l v e n t r i c u l a r f i b r i l l a t i o n . New England J o u r n a l o f M e d i c i n e , 1975, 293, 260-262. 101. Schulberg, H. C, Sheldon, A., £ Baker, F. Program evaluation in  the health fields. New York: Behavioral Publications, 1969. Schwartz, fl. L. Emergency coronary outside the hospital. Postgraduate Tfedicine, 1974, 56, 119-120. Selltiz, C., Wrightsman, L. S., £ Cook, S. W. Research methods in  social relations. 3rd Edition. New York: Holt, Rinehart and Winston, 1976. Sherman, M. A. Mobile intensive care units. An evaluation of effectiveness. Journal of the American Medical Association, 1979, 241, 1899-1901. Shortell, S. M., & Richardson, W. C. Health program evaluation. Saint Louis: C.V. Mosby Company, 1978. Shu, C. Y. Mobile CCU's. Hospitals, 1971, 45, 14. Sidel, V. W., Acton, J., £ Lown, B. Models for the evaluation of pre-hospital coronary care. American Journal of Cardiology, 1969, 24, 674-688. Simon, A. B., Feinleib, M., £ Thompson, H. K., Jr. Components of delay in the pre-hospital phase of acute myocardial infarction. American Journal of Cardiology, 1972, 30, 476-482. Smith, Carson. Verbal communication, 1982 with the Executive Director of the Emergency Health Services Commission in British Columbia. Stallones, R. A. The rise and fall of ischaemic heart disease. Scientific American, 1980, 243, 53"59. Standards for cardiopulmonary resuscitation (CPR) and emergency cardiac care (ECC). Journal of the American Medical Association, 1974, 227, Suppl., 833-868. Statistics Canada. Causes of death—1978. Provinces by sex and  Canada by sex and age. Ottawa: Statistics Canada, Health Division, Vital Statistics and Disease Registries Section, 1980. Statistics Canada. Population and dwellings, Canada, census figures 1981. Ottawa: Unpublished Working Document, p. 100, W T Steel, K. , Cooper, J., Fox III, S. M. Mobile coronary services. Editorial. Circulation, 1969, 39, 279-281. Stern, M. P. Ischemic heart disease: an epidemic on the wane? American Journal of Surgery, 1981, 141, 646-650. 102. Stewart, R. D. Today's cure—tomorrow's poison. Journal of the American College of Emergency Physicians, 1977, 6, 571• Suchman, E. A. Evaluative research. Principles and practice in  public service & social action programs. New York: Russel Sage Foundation, 1967. Thompson, H. K. , Jackson, P. M. , Mattox, K. L. , £ Mcintosh, H. D. Impact of ambulance life support on outcomes of cardio-vascular emergencies. Heart £ Lung, 1979, 8_, 486-494. Thorner, R. M. Health program evaluation in relation to health programming. In, Schulberg, H. C, £ Baker, F. (Eds.), Program evaluation in the health fields. Vol. II. New York: Human Sciences Press, 1979. Tresch, D. D., Grove, J. R., Keelan, M. H., Jr., et al. Long-term follow-up of survivors of prehospital sudden coronary death. Circulation, 1981» 64(2 Pt. 2), 1-6. Tweed, W. A., Briston, G., £ Donen, N. Evaluation of hospital-based cardiac resuscitation 1973-77. Canadian Medical  Association Journal, I98O, 122, 301-304. (a) Tweed, W. A., Bristow, G., £ Donen, N. Letter to the Editor. Canadian Medical Association Journal, 1980, 123, 122-123. (b) Tweed, W. A., Bristow, G., £ Donen, N. Resuscitation from cardiac arrest: assessment of a system providing only basic life support outside of hospital. Canadian Medical Association  Journal, I98O, 122, 297~304. (cl Tweed, W. A., £ Wilson, E. Heart-alert: emergency resuscitation training in the community. Canadian Medical Association  Journal , 1977, JJ_7, 1399-1403. U.S. Department of Health, Education £ Welfare. Proceedings of the  conference on the decline in coronary heart disease mortality. NIH Publ. No. 79-1610. Bethesda, 1979-U.S. Department of Health and Human Services. Health United States, 1980. Section I: the illness burden that prevention could  reduce. PHS 81-1232. Hyattsvi11er, Md.: Office of Health Research Statistics £ Technology, 1980. Urban, N., Bergner, L. , £ Eisenberg, M. S. The costs of a sub-urban paramedic program in reducing deaths due to cardiac arrest. Medical Care, 19.81 , j_9, 379-39.2. 103. Vaistrub," S. The race against time. Journal of the American Medical Association, 1971, 216, 3W. Vertesi, Les. Verbal communication 1977-1982 with the current Medical Director of the Advanced Life Support Program, Emergency Health Services Commission of British Columbia. Vetter, N. J., Pocock, S., & Jul Tan, D. G. Measuring the effect of a mobile coronary care unit upon the community. Br i t i sh  Heart Journal , 1979, 4]_, 418-425. Wallace, W. A., & Yu, P. N. Sudden death and the pre-hospital phase of acute myocardial infarction. Annual Review of  Medicine. Selected Topics in the Clinical Sciences, 1975, 26, 1-7. " Webb, S. W. Mobile coronary care. (Letter). Lancet, 1974, J_, 559~560. Webster, A. C. Out-of-hospital resuscitation from cardiac arrest. Letter to the Editor. Canadian Medical Association Journal, 1980, T23_, 174-176. Weiss, C. H. Evaluation research. Englewood Cliffs, N. J.: Prentice-Hall, Inc., 1972. White, N. M. , Parker, W. S., Binning, R. A., et al. Mobile coronary care provided by ambulance personnel. British Medical Journal, 1973, 3, 618-622. Willemain, T. R. The status of performance measures for emergency medical services. In, Emergency medical systems analysis.  Papers on the planning and evaluation of services. Vol. IV. Urban public safety systems. Toronto: Lexington Books, 1977. Willemain, T. R., & Larson, R. C. (Eds.) Emergency medical systems  analysis. Papers on the planning and evaluation of services. Vol. IV. Urban public safety systems. Toronto: Lexington Books, 1977. Winkelstein, W., Jr. Epidemiological considerations underlying the allocation of health and disease care resources. International  Journal of Epidemiology, 1972, J_, 69-74. World Health Organization. Mobile coronary care units. WHO  Chronicle, 1971, 25, 79 - 82 . Yu, P. N. A stratified system of coronary care. Circulation, 1971, 44, 979-981. Zipes, D. P., Heger, J. J., & Prystowsky, E. N. Sudden cardiac death. Editorial. American Journal of Medicine, 1981, 7_0, 1151-1154. 104. APPENDIX A Part 1 Advanced Life Support is basic life support plus use of adjunctive equipment, intravenous fluid lifeline (infusion), drug administration, defibrillation, stabilization of the victim by cardiac monitoring, control of arrhythmias, and postresuscitation care. Also it includes establishing necessary communication to ensure continuing care, and maintaining monitoring and life support until the victim has been transported and admitted to a continuing care facility. Advanced life support requires the general supervision and direction of a physician who assumes responsibility for the unit. It must have adequate communications on a 24-hour-per-day basis. This may necessitate appropriate legislation or standing orders for implementation (Standards for Cardiopulmonary Resuscitation, 1974 , pp. 8 3 8 - 8 3 9 ) . Part 2 The Emergency Health Services Commission has determined that ten people are required to staff a single EHS vehicle providing service 168 hours a week, considering sick time, holidays and education days. An EMA III vehicle required support by an EMA II vehicle, and therefore takes a portion of the EMA II vehicle out of service from the point of view of the ambulance service as a whole. It is therefore deemed appropriate to add to the cost of operating the EMA III vehicle a portion of the cost of operating the EMA II vehicle which supports it. See page 2 for these calculations. 105. APPEND\X A, Page 2 ESTIMATED COST IN 1981-1982 DOLLARS OF OPERATING A SINGLE EHS VEHICLE FOR 1 YEAR ** EMA I I I EMA I I COSTS VEHICLE VEHICLE Personnel: $ 410,000 $ 330,000 - 10 people per vehicle, plus employee benefits Vehicle Operation & Support: 75,000 60,000 - administrative and dispatch services; maintenance; gas; drugs; depreciation, etc. Continuing Education: - 10 staff, overtime payment 6,000 3,200 - direct continuing education costs 6,250 1,000 Monitoring Physician and ^ gg^  Emergency Medical Council: ' Miscellaneous Costs: 12,500 12,500 Total: $ 520,630 $ 406,700 To the cost of operating the EMA III vehicle, however, is added eighty-five per cent of the cost of operating the EMA II vehicle which provides support to it. TOTAL COST OF OPERATING AN EMA III VEHICLE FOR 1 YEAR: (ESTIMATE) EMA III Vehicle Cost $ 520,630 + .85 EMA II Vehicle Cost 345,695 TOTAL: ==§11=225 TOTAL COST OF OPERATING AN EMA II VEHICLE FOR 1 YEAR: (ESTIMATE) TOTAL: ======22°= Based on personal communication: Mr. Carson Smith, Executive Director, Emergency Health Services Commission, 1982. UJ VANCOUVER USE ONLY U PATIENT'S SURNAME PROvince O F B R I T I S H c o L u m B i a emeRGencY HeatTH seRvices commission APPENDIX B CREW REPORT fcj DATE OF SERVICE DAY MO. I I I I I OPERATOR No. J a _ P J S T A T I O N / C R E W D E S . J I I . I RESPONSE No. -I 1 L 1 I L. PROV. DISPATCH No. -I 1 L_ I I I WARNING SYSTEM USED FROM SCENE ORIG. 2 3 U FIRST OR GIVEN NAME U STREET ADDRESS C H G . 2 3 INIT. „ U CITY"OR TOWN Li PROVINCE l S ? o , ? . £ S ^ B I L L I N G NAME OR NAME OF EMPLOYER • ABOVE 1 • . t i l STREET ADDRESS IO POSTAL CODE -1 1 1 I L ORIG. 2 3 C H G . 2 3 UJ SOCIAL INSURANCE No. I- I I I I | til TELEPHONE No. W SPECIAL CODES 1 1 1 1 1 1 J L 1 1 L J _ i l l BIRTHDATE DAY MO I I I J -i y AGE pa S E X KU CITY OR TOWN LJ PROVINCE £1 UNIT RESPONDED TO iii PATIENT CARRIED TO El POSTAL CODE PATIENT FOUND IN pr POSITION FOUND IN W MEDICAL CONDITION m 1 1 1 1 1 i H ATTENDING PHYSICIAN till CAR NO. J l_ J L 1 1 1 1 I I I I E3 M.V. LICENCE NO. LU IDENTIF ICATION^ " IDENTIFICATION NO. til INVESTIGATING AGENCY ta INVESTIGATING OFFICER OFFICE USE ONLY Ul ESCORT/TRAINEE/OBSERVER NAME TRAUMA TYPE OR CAUSE OF INJURY pr TRAUMA LOCATION ON BODY pr SYMPTOMS pr p r START P SCENE o DESTINATION pr BASE ill DRIVER NAME kl ATTENDANT NAME KM READINGS J 1 1 L J I I l_ J 1 I -I J 1 I L iii DRIVER NO. J 1 I L VITAL S I G N S PRESENT ABSENT • • TREATMENT PATIENT CARRIED ON/IN EjU ATTENDANT NO J I I L " TREATMENT OTHER TREATMENTS P> PATIENT DISPOSITION 20 NO PATIENT 21 PERSONAL RESIDENCE 22 HOTEL/MOTEL ROOM 23 PLACE OF EMPLOYMENT 24 PUBLIC BUILDING 25 PUBLIC STREET/ROAD 26 OTHER AMBULANCE 27 AIRCRAFT ' 28 OTHER TRANS P0RTATI0N 29 CLINIC. DR'S. OFFICE 30 ACUTE CARE HOSPITAL 31 N HOME CHRONIC C 32 OTHER 40 STANDING 41 SITTING 42 SEMI-RECLINING 43 SUPINE 44 SEMI-PRONE 45 PRONE 46 HANGING 47 ENMESHED 48 OTHER 50 INFECTIOUS 51 METABOLIC DISORDER 52 NEOPLASM 5^3 CARDIAC ' * * ~ / CIRCULATION 54 PERIPHERAL CIRCULATORY 55 NEUROLOGIC 56 SKELETAL 57 PREGNANCY 58 REPRODUCT. OTHER -60 RENAL 61 DIGESTIVE- ' C3E SESIfRATOKT 83 HEPATIC LIVER 70 BLAST 71 BURNS . CHEMICAL BURNS THERMAL 64 DERMAL/ S K I N 65 PSYCHIATRIC 66 OTHER " B U R N S ELECTRICAL 74 INGESTED CHEMICALS TOXIC 75 INJECTED CHEMICALS TOXIC 76 COUfSION 77 FALL 78 PENETRATE. 79 CRUSHING DROWNING 8J EXPOSURE 82 ELECTRO-CUTION 83 ABRASIONS/ LACERATIONS 84 FRACTURES 85 DISLOCATION 90 INTER-PERSONAL VIOLENT 91 SELF INFLICTED 92 MOTOR VEH. 93 OTHER CONVEYANCE 94 MECHANICAL EQUIPMENT 95 FIRE/ EXPLOSION ELECTRICAL CONTACT 96 97 RADIATION 98 TOXIC CHEMICALS 99 FIREARMS 100 OTHER 2^0 SKULL U I F A C E 122EVE(S) 123EAR(SJ 124 NECK 125 BACK 126 CHEST 127 ABDOMEN 128 PELVIS 129 UPPER L£G(S> 130 KNEE(S) 131 LOWER L E G S ) 132FOOT/ ANKLETS) 133 UPPER ARMTS)/ SHOULDR(S) 134 FOREARM(S) / E L B O W S ) 135HAN0(S)/ WRIST(S) 136 OTHER 150 PAIN AT REST 151 PAIN ON MOVEMENT 152 PAIN ON SWALLOWING 153 PAIN ON BREATHING 154 PAIN ON. EXCRETION I K FEELS COLD 156 FEELS HOT 157 FEELS WEAK 158 NAUSEOUS 159 DIZZINESS IK) LOSS OF SENSATION PARTIAL 161 LOSS OF SENSATION COMPLETE 162 VISION IMPAIRED 163 VISION ABSENT ' 164 AGITATION AND HYPERACTIVE I K OTHER. 170 EXTERNAL BLEEDING 171 BLEEDING FROM BOD' ORIFICE 172 SKIN PALE 173 SKIN FLUSHED 174 SKIN BRUISED 175 EXCESSIVE PERSP. 176 VOMITING 177 DIARRHEA 178 SHIVERING 179 TREMORS 180 CONVULS'N 181 ODOR ON BREATH 182 ABNORMAL BEHAVIOR LEVEL OF CONSC. P SI U ? Fl SIZE L L REACT LI] COMMENTS VES NO • • 183 DEFORM I 184 SWELLIN EDEMA 185 OTHER B.P. 3)0 MAIN COT 201 AUXILIARY ' STRETCHER 202 FULL SPINEB0ARD 203 FRAME 204 14 SPINE-BOARD . 205 SITTING 206 IN ARMS 207 OTHER 230AIR PASSAGE CLEARED 231 AIRWAY PLACED 232 INTUBATED 233 SUCTIONING 234 0 , ADMINIS-TRATED 235 VENTILATION ASSISTED 236 CARDIAC COMPRESS 260 PERSONAL r RESIDENCE 261 OTHER AMBULANCE 262 AIRCRAFT 263 OTHER TRANSPORT 264 CLINIC DR. OFFICE 265 PATIENT POSITIONED 228 SITTING 221 SEMI-SITTING 222 SUPINE 223 SEMI-PRONE 224 PRONE 225OTHER 237 MONITORED 238 DEflBRILLA TION 9 CARDIAC OR OTHER MEDICATION 240 i.v. STARTED 241 DRESSINGS APPLIED 242uMB(S) SPLINT OR IMMOBILIZE 243TRUNK IMMOBILIZE 244CERVICAL COLLAR 245SANDBAGS 246 RESTRAINTS 247 OTHER ACUTE CARE HOSPITAL m— *™ DURING TRANSPORTATION AND CARE PATIENT'S CONDITION IMPROVED DETERIORATED REMAINED SAME 1 266 NURSING HOME 267 CHRONIC CARE 268 MORGUE 269 OTHER 270 ANU 271 PATIENT REFUSED ABOVE ITEMS REC'D BY LU BILLING STATUS IF HOLD, NO CHARGE, OR BILLED 13 AGENCY OFFICE HI 1 1 HOURS a El BILL TYPE OFFICE USE ONLY BASIC AMOUNT = 1 1 1 J. 1 * 1 DISTANCE CHARGE = 1 1 1 1 1 * 1 TIME CHARGE = m 1 i 1 a SUB-TOTAL = i i 1 A 1 13 —ADJUSTMENTS = i i 1 4 1 FINAL AMOUNT = LJ 1 1_. 1 i 1 C O M M I S S I O N - DATA ENTRY 107. DATE: S t a t i on: D i s p a t c h No. GIVEN NAME: C a r d i a c A r r e s t Case: CHIEF COMPLAINT ( c h e c k only one) • Chest P a i n • S.O.E. Q P a l p i t at i o n s -Q C o l l a p s e • Other: [ipeciitj] SEX • M D F Day D.O.B. Mo. OTHER SYMPTOMS HISTORY RELEVANT TO THIS ILLNESS PAST MEDICAL HISTORY MEDICATIONS • ~Yc • No Yr . INITIAL VITAL SIGNS: BP Heart Rate R e s p i r a t i o n Rate LEVEL OF CONSC. [j F u l l y a l e r t • S e m i - a l e r t r j U n c o n s c i o u s , but r e s p . t o p a i n U n c o n s c i o u s - no r e s p o n s e t o p a i n SKIN COLOR n Normal Q F l u s h e d • P a l e [ ] Cyanosed • PULSE • S t r o n g p u l s e Q E a s i l y p a l p a b l e , b> weak • B a r e l y p a l p a b l e Q N o n e p a l p a b l e PROVISIONAL DIAGNOSIS D S u s p e e t e d a c u t e Ml • S u s p e c t e d pulmonary edema • S u s p e c t e d c a r d i a c a r r h y t h m i a • C a r d i a c a r r e s t . • O t h e r Up£CAj$!/) PROCEDURES PERFORMED • 0., by mask • Ambubag v e n t i l a t i o n Q C P R Q O t h e r {ipe.ci.iij) NAME OF ARRIVAL HOSPITAL P r i o r N o t i f i c a t i o n Made: • Yes-Q No -4 I f " y e s " , s p e c i f y method: CONDITION ON ARRIVAL AT HOSPITAL: BP Heart Rate R e s p i r a t i o n R a t e : DISPOSITION: LEVEL OF,CONSC. D F u l l y a l e r t • S e m i - a l e r t Q U n c o n s c i o u s , but r e s p . t o p a i n r j U n c o n s c i o u s - no r e s p o n s e t o p a i n • A d m i t t e d t o Emergency • D i r e c t H o s p i t a l A d m i s s i o n • D.O.A. SKIN COLOR Q Normal • F l u s h e d Q P a l e Q C y a n o s e d PULSE • S t r o n g p u l s e • E a s i l y p a l p a b l e , b u t weak Q B a r e l y p a l p a b l e Q N o n e p a l p a b l e IN-HOSPITAL COURSE U|$ known) CPR b e i n g done on a d m i s s i o n ? • Yes C J N O FOR CARDIAC ARREST CASES ONLY • CPR done b e f o r e QIA II a r r i v a l : Ic/iecfe p>;e Q.\ mold vi thua) • by l a y p e r s o n Q b y F i r e Dept. • by h e a l t h p r o f e s s i o n a l EFFECTIVE CPR • • N o CPR b e i n g done b e f o r e EMA II a r r i v a l E s t i m a t e d t i m e i n a r r e s t b e f o r e EMA II a r r i v a l E s t i m a t e d time i n a r r e s t p r i o r t o any CPR A s p i r a t e d ? T h i s p a t i e n t was: • f o u n d i n a r r e s t - Was t h e a r r e s t o b s e r v e d by anyone? Q Yes • a r r e s t e d d u r i n g a t t e n d a n c e • No PRESUMED. CAUSE OF ARREST: ED C a r d i a c M O r h . - r i M - C C < • T r n u m n t i c EMA I I A t t e n d a n t (n'flnrrf) l i . ' io i i i:.".r\ APPENDIX C - PART 2  CARDIAC ARREST DATA SHEET 108. INFORMATION Case No. Date : H o s p i t a l : Name: Age : Sex: (M=l, F=2) EMA I I . : EMA I I I : D o u b l e : S e c o n d a r y : (2) (3) (4) (5) U n k . (9) S t a t i o n No.: . D i s p a t c h No.: Time R e c e i v e d : 1007 (@) Time f r o m c a l l t o d e f i n i t i v e t r e a t m e n t : M i n s . No CPR b e i n g done on a r r i v a l ? (Y = l , N=2, Unk=9 i n f o . Not A p p l i c a b l e = 8) By whom? ( l a y p e r s o n = l , F i r e Dept.' =2, h e a l t h p r o f n l . = 3 o t h e r = 4 , Unk.=9, Not A p p l i c a b l e = 8 ) E f f e c t i v e CPR? (Y = l , N=2, No i n f o . = 9 , Not appl.=8) E s t i m a t e d t i m e i n a r r e s t b e f o r e EMA a r r i v a l : M i n s . (No i n f o . = 9 9 9 , Not a p p - l i c a b l e = 888) E s t i m a t e d t i m e i n a r r e s t b e f o r e any CPR: M i n s . (No i n f o . = 9 9 9 , Not a p p 1 i c a b l e = 8 8 8 ) A s p i r a t e d ? : (Y = l , N=2 , No. i n f o . = 9 ) P a t i e n t was: ( f o u n d i n a r r e s t = l , a r r e s t e d d u r g a t t e n d = 2 ) A r r e s t w i t n e s s e d ? (Y = l , N=2 , No i n f o . = 9 , Unk.=9) Presumed c a u s e o f a r r e s t : ( C a r d i a c = l , T r a u m a t i c = 2 , 0 v e r d o s e = 3 , 0 t h e r = 4 , Unk.=9) P a t i e n t d i s p o s i t i o n : (D0A=1, A d m i t t e d Emerg.=2, D i r e c t H o s p i t a l Admissn=3, Unk.=9) HOSPITAL INFORMATION ER D i a g n o s i s : ( C a r d i a c = l , O t h e r = 2 , Unk.=9) ER D i s p o s i t i o n : ( D i e d i n ER=1, A d m i t t e d ICU/CCU=2, 0 t h e r = 3 , Unk.=9) I n - H o s p i t a l C o u r s e : D i e d i n H o s p i t a l = l D a t e : D i s c h a r g e d A l i v e = 2 D a t e : L e n g t h o f H o s p i t a l i z a t i o n i n d a y s : APPENDIX E 110. TABLE I: NUMBER AND PERCENTAGE DISTRIBUTION OF AGES OF STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT AGE EMA 11 EMA 1 1 1 TOTAL H (%) U Cl) N (1) 50 6 ( 6.7) 21 ( 9.3) 27 C 8.5) 50-69 44 (48.9) 105 (46.5) 149 C47.2) 70 4o (44.4) 100 (44.2) 140 (44.3) Total 90 226 316 X = 0.60 p. = 0.74 TABLE I I: NUMBER AND PERCENTAGE DISTRIBUTION BY SEX OF STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT SEX EMA 1 1 EMA 1 1 1 TOTAL H tl) H Cl) N (1) Male 66 (73.3) 162 (69.5) 228 (70.6) Fetna 1 e 24 (.26.7) 71 (30.5) 95 C29.4) Total 90 233 323 Corrected X = 0.29 p. = 0.59 TABLE III: NUMBER AND PERCENTAGE DISTRIBUTION BY TIME OF DAY OF INCIDENT FOR STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT TIME OF DAY EMA 1 1 EMA 111 TOTAL N (1) N (%) N (1) Day (0800 - 1800) 48 (52.7) 144 (61.8) 192 (59-3) Night (1801 - 0759) Total 43 e»7.3) 89 C38.2) 132 (40.7) 91 233 324 Corrected X = 1.86 111. APPENDIX E TABLE IV: NUMBER AND PERCENTAGE DISTRIBUTION OF OUTCOMES  FOR STUDY PATIENTS FOUND IN ARREST BY TYPE OF RESPONDING ATTENDANT OUTCOMES - Initial Outcome Admi tted Alive to Ward/ Special Unit Died Before Admi ss ion EMA I I PAT IENTS N (%) EMA III PATIENTS N (%) STATISTICAL TEST 6 ( 7.9) 70 (92.1) 55 (26.3) 154 (.73.7) Corrected X = 10.2 p.= 0.001 Course in Hospital for Patients Admitted Alive Died in Hospital Discharged Alive 4 (66.7) 2 (33.3) 31 (55.4) 25 (44.6) Fisher's Exact p.= 0.69 (2-tailed) - Final Outcome (Total Patient Group) Died At Any Time Di scharged Alive 74 (97.4) 183 (88.0) 2 ( 2.6) 25 (.12.0) Corrected X = 4.7 p.= 0.03 112. APPENDIX E TABLE V: NUMBER AND PERCENTAGE DISTRIBUTION OF OUTCOMES  FOR STUDY PATIENTS ARRESTING DURING ATTENDANCE BY TYPE OF RESPONDING ATTENDANT OUTCOMES Initial Outcome Admitted Alive to Ward/ Special Unit Died Before Admi ss ion EMA H PAT IENTS N {%) EMA 1 I I PATIENTS N (%) STATISTICAL TEST 4 (28.6) 10 (47.6) 10 (71.4) 11 (52.4) Corrected X = 0.6 p.= 0.44 - Course in Hospital for Patients Admitted Alive Died in Hosp i ta1 1 (25.0) 5 (55.6) Fisher's Exact p.= 0 Di scharged Al ive 3 (75.0) 4 (44.4) (two-ta iled) - Final Outcome (Total Patient Group) Died At Any Time 1 1 (78.6) 16 (80.0) Fisher's Exact p.= 1 Di scharged Al ive 3 (21.4) 4 (20.0) (two-ta i1ed) 113 . APPENDIX E TABLE VI: TIME IN ARREST WITHOUT CPR BY TYPE OF RESPONDING ATTENDANT: MEAN TIME/MEAN TIME FOR LOG-TRANSFORMED DATA AND t-TEST ON LOG-TRANSFORMED DATA MEANS MEAN LOG-TRANSFORMED DATA MEAN STATISTICAL TEST EMA I I EMA I I 5.7 5.5 1.8 1.7 Separate variance estimates used: t = 0.75; P. = 0.45 TABLE VII: MEAN TIMES AND SKEW FOR TIME tN ARREST WITHOUT CPR  BY TYPE OF RESPONDING ATTENDANT FOR ORIGINAL AND LOG-TRANSFORMED DATA EMA I I Mean: 5-7 Skew: 0.7 EMA II Mean on log-transformed data 1.8 Skew: -0.6 EMA III Mean: EMA III Mean on log-transformed data: 5.5 1.7 Skew: Skew: 0.7 -0.7 114. APPENDIX E TABLE VIII; NUMBER AND PERCENTAGE DISTRIBUTION OF OUTCOMES  FOR STUDY PATIENTS RECEIVED BY HOSPITALS WITH AND WITHOUT CORONARY CARE UNITS OUTCOME HOSPITAL WITH CCU HOSPITAL WITHOUT CCU STATISTICAL TEST Initial Outcome N (%) Admi tted Alive to Ward/ Special Unit Died Before Admi ss ion 66 (25.6) 192 (.74.4) N (%) 9 0 9 . 1 ) 38 (.80.9) Corrected X = 0.57 p.= 0.45 - Course in Hospital for Patients Admitted Alive Died in Hospi tal 37 (56.1) 4 (44.4) Fisher's Exact p.= 0.72 Di scharged Al ive 29 (43.9) 5 (55.6) (two-ta ?led) - Final Outcome (Total Patient Group) Died At Any Time 227 (88.7) 42 (89.4) 2 Corrected X = 0.0 Di scharged Alive 29 (11.3) 5 (10.6) p.= 1.0 APPENDIX E TABLE IX: MEDIAN TIME TO DEFINITIVE CARE FOR STUDY PATIENTS BY TYPE OF RESPONDING ATTENDANT MEDIAN IN MINUTES EMA I I Patients EMA III Patients STATISTICAL TEST Mood Median X = 129-9 p.= 0 . 0 0 TABLE X: MEDIAN LENGTH OF HOSPITALIZATION FOR STUDY  PATIENTS DISCHARGED ALIVE BY TYPE OF RESPONDING ATTENDANT MEDIAN IN DAYS EMA I I Pat ients EMA III Patients STATISTICAL TEST Mood Median X = 0 . 2 9 P-= 0 . 5 9 APPENDIX E TABLE X\: MEDIAN LENGTH OF HOSPITALIZATION FOR STUDY  PATIENTS WHO DIED IN HOSPITAL BY TYPE OF RESPONDING ATTENDANT MEDIAN IN DAYS STAT I ST ICAL TEST EMA I I Patients EMA I I I Patients Mood Median X = 2.63 p.= 0.11 TABLE XII: MEDIAN LENGTH OF HOSPITALIZATION FOR STUDY  PATIENTS WHO DIED IN HOSPITAL COMPARED TO STUDY PATIENTS WHO WERE DISCHARGED ALIVE MEDIAN IN DAYS STAT I ST ICAL TEST Patients Who Died in Hospital Patients Discharged Al ive Mood Median X = 26.2 p. = 0.00 

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