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Head injuries in the rural setting : what is the role of the Canadian CT head guidelines 2006

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HEAD INJURIES IN THE RURAL SETTING: WHAT IS THE ROLE OF THE CANADIAN CT HEAD GUIDELINES? by FERN V O N DER PORTEN B . S c , The University of Victoria, 1997 M.D. , The University of British Columbia, 2001 C C F P , The University of Brit ish Columbia, 2003 C C F P - E M , McMaster University, 2004 C A S M & Fellowship Sports Medicine, The University of Brit ish Columbia, 2006 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE F A C U L T Y OF GRADUATE STUDIES (Human Kinetics) THE UNIVERSITY OF BRITISH COLUMBIA December 2006 © Fern von der Porten, 2006 ABSTRACT The Canadian C T head rule is a valuable tool in the clinical assessment of head injuries. It risk stratifies head injured patients, identifying the ones that wi l l require neurological intervention and the ones having clinically important brain injuries (sensitivities 100% and 98.6%, respectively). This standardized approach to head injuries may challenge the rural practitioner without access to C T scan. The Whistler Health Care Center ( W H C C ) is a Diagnostic and Treatment Centre seeing approximately 23,000 patients annually, many of them trauma patients with a high acuity level. There is no C T scanner on site. This provides a unique setting to study head injuries: a large number of head-injured patients with limited diagnostic tools, like many other rural facilities in Canada. It was hypothesized that fol lowing the Canadian C T Head Guidelines at the Whistler Health Care Center would have increased the number of scans performed. This study is a retrospective chart review of all patients triaged with head injury, or trauma, to the W H C C in 2004. Canadian C T head guidelines were applied to all charts, and were risk stratified according to the guidelines. 516 charts were reviewed, 305 of which were excluded (5 GCS<13, 1 pregnant, 5 seizures prior to assessment, 56 no amnesia, L O C or disorientation, 38 follow-ups, 174 age < 16 yrs, 22 not seen by M D , 1 acute neurological deficit, 1 unstable vitals, 1 depressed skull fracture, 1 anticoagulant use), and 211 were included. O f the 211 included charts, 51 had C T indicated, and only 4 of these were transferred to a health care facility with C T scan available. A further 9 patients, without meeting the C T criteria were also transferred. The W H C C has a high number o f head injuries annually. When the Canadian C T head guidelines are applied, a greater number of scans are indicated. Some scans, however, in the minor risk group, could have been avoided. When the C T head guidelines are applied to the rural setting without diagnostic C T , patients with high-risk criteria should all be transferred. A prospective study in a similar setting is recommended to determine the management of moderate risk patients. i n TABLE OF CONTENTS Abstract ii Table of Contents iv List of Tables v List of Figures vi Acknowledgements vi i I N T R O D U C T I O N 1 L I T E R A T U R E R E V I E W 2 O B J E C T I V E S A N D H Y P O T H E S E S 11 M E T H O D S 12 R E S U L T S 15 D I S C U S S I O N : '. 23 Bibliography •• 37 Appendix I Data Collection Form 41 Appendix II Ethics Certificate of Approval 42 i v LIST OF TABLES Canadian C T Head Rule 6 Cases Having Exclusion Criteria 16 Cases Not Meeting Inclusion Criteria • 17 Charts Not Meeting Criteria 17 Included Chart 18 Result Summary 20 Disposition Summary 20 Acuity Levels 21 Injury from Sport • '• 21 v LIST OF FIGURES Alaska Trauma Head Guidelines 9 Patient Disposition. 21 Comparison of Outcomes 28 Rural Canadian CT Head Guidelines 36 - vi ACKNOWLEDGEMENTS Special thanks to Dr. Jack Taunton Dr. Bruce Forster Dr. Rob Lloyd-Smith Dr. Navin Prasad Dr. Annie Gareau Dr. Stephan Gryzbowski Dr. Jonathan Berkowitz Dr. Bruce Mohr Nancy McLaren WHCC office staff Whistler Health Care Foundation BC Sports Medicine Research Foundation University of British Columbia Department of Family Practice Sports Medicine Clinical Investigator Program Enhanced Skills Program INTRODUCTION Head injury is a very common presentation to the Emergency Department (26). Some conditions, if undiagnosed, can have serious consequences (28, 23). Until recently there was no consensus about the use of imaging in the diagnosis and subsequent management of minor head injury (25, 27, 28) The Canadian CT head rule is a valuable tool in the clinical assessment of head injuries. It risk stratifies head injured patients, and identifies patients requiring neurological intervention and those having clinically important brain injuries, with sensitivities of 100% and 98.6%, respectively. This standardization in approach to head injuries highlights the challenge to the team physician or rural practitioner, who must make clinical decisions without the benefit of a CT scan. The Whistler Health Care Center is a Diagnostic and Treatment Facility that has an annual patient census of approximately 23,000, with a high number of trauma patients. The average Canadian Triage Acuity Scale (CTAS) score for head injury patients in Whistler is 2 (emergent). The amount of trauma and sport-related injuries seen in the clinic is out of proportion to what would normally be expected in a rural setting. There is no CT scanner on site. This situation poses a unique opportunity, in that there are a higher number of patients with head injuries at the WHCC, yet there are the limited diagnostic tools like most rural settings in BC. 1 LITERATURE REVIEW Many head injuries seen in the emergency department occur during sport (20,22). It is estimated that there are 300, 000 sport related concussions per year in the US (25). Head injury is the most serious type of sport related injury, with a 9% hospital admission rate, compared to 4% from other types of sport related injuries (26). Most head injuries are mild, and the athlete makes full recovery with return to sport (21). Other head injuries, however, have serious consequences, with acute neurological deterioration or acquired brain injury (23,26). There is controversy about the use of C T scanning in concussion and sport head injury (21, 24, 28). The Vienna group advises against the use of C T unless a structural lesion is expected, there is a progressively worsening headache, or there is a decline in mental status (27). Others have found that no clinical variables are predictive of abnormal C T (29), and that neuroimaging does not account for signs and symptoms following head injury in athletes. (24) Head injuries are one of the most common types of trauma seen in Emergency Departments in North America (16). Injury is the leading cause of death in the under 45- age group; 50% of which are caused by head trauma (18). The majority of head trauma, however, is minor, with an estimated 1 million emergency visits per year in the United States (7). Mi ld head injuries are generally defined by a loss of consciousness, amnesia, 2 f or disorientation in a patient who is conscious and talking (Glasgow Coma Scale 13-15). (16) Glasgow Coma Score is a widely used scoring system used to rate level of consciousness. It is made up of three components: eye opening, and eye and motor response (19). The scoring ranges from 3-15, depending on best response according to these criteria: Best Eye Response /4 (1. No eye opening, 2. Eye opening to pain. 3. Eye opening to verbal command. 4. Eyes open spontaneously), Best Verbal Response 15 (1. N o verbal response 2. Incomprehensible sounds. 3. Inappropriate words. 4. Confused 5. Orientated) and Best Motor Response /6 (1. N o motor response. 2. Extension to pain. 3. Flexion to pain. 4. Withdrawal from pain. 5. Local izing pain. 6. Obeys Commands). Head injuries have a wide range in outcomes, ranging from asymptomatic to death. The challenge to the practitioner is to identify patients requiring surgery or medical management. The brain can receive different types of injury depending on the direction and force that impacts the head. Primary brain injury occurs immediately upon impact, whereas secondary injury occurs after the event from neurophysiologic and anatomic changes at the cellular level. Types of traumatic brain injury include concussion, skull fractures and intracranial hematomas (2). There are several forms of intracranial hematoma. Bleeding between the skull and dura, typically arising from the middle meningeal artery, causes an epidural hematoma. Subdural hematomas form between the dura and brain, and intracerebral hematomas are contusions to the brain. Diffuse axonal injury (DAI) is the disruption of axonal fibers in the brain cased by shearing forces on the neurons in sudden deceleration. C T scan of D A I is often normal (19). In centers with C T scanners, this more accurate and useful imaging modality has replaced plain skull radiographs. Computed tomography (CT) is the diagnostic procedure o f choice for acute head injury, while magnetic resonance imaging (MRI) has great value for evaluation in the sub-acute and long-term (4). Early scanning of moderate and severe head injuries is common practice (8), yet in mild/ minor head injury, diagnostic approaches vary widely between centers (13,14). Unti l recently, no guidelines have been able to reliably predict C T abnormalities based on clinical findings (2,5,8,11,14). The Canadian C T Head Rule was developed to guide the use of C T scanning in adults with minor head injuries. Stiell et al. (17) carried out a prospective cohort study in the emergency departments of ten large Canadian hospitals, to study patients presenting with minor head injuries (17). The goal was to develop a highly sensitive and clinically sensible decision rule, similar to the Ottawa Ankle and Knee Rules. Some data indicate that low-dose radiation (such as that in CT) may have a significant risk of cancer, especially in young children, therefore, it is important to limit C T radiation (30). This increased risk is presumed to be part of the reason why the under 16-year age group was excluded from this study. Further research in this area is ongoing, with a multi-center study currently underway. 4 The Canadian C T Head Rule defines populations at high risk for neurological intervention and medium risk for brain injury on CT . The high risk patients are those with a G C S score <15 at 2 hours after injury, suspected open or depressed skull fracture, any sign of basal skull fracture, vomiting >2 episodes or age >65 years (17). The medium risk patients are those with either amnesia before impact >30 minutes, or a dangerous mechanism (pedestrian struck by a motor vehicle, occupant ejected from a motor vehicle, or a fall from >3 feet or 5 stairs). The clinical decision rule identifies patients requiring neurological intervention and those having clinically important brain injuries, with sensitivities of 100% and 98.6%, respectively (17). In the development of the C T head rule, 24 predictor variables were correlated with outcomes. Logistic regression and recursive partitioning were used to determine the seven criteria used in the Canadian C T Head Rule (17). 5 Table 1. Canadian CT Head Rule C T head scan is only required for patients with minor head injury with any one of these findings: High-risk (for neurologic intervention) 1. G C S score at 2 hours after injury 2. Suspected open or depressed skull fracture 3. Any sign of basal skull fracture (hemotympanum, "raccoon" eyes, C S F otorrhea/rhinorrhea, Battle's sign) 4. Vomit ing > 2 episodes 5. Age > 65 years Medium-risk (for brain injury on CT scan) 6. Amnesia before impact > 30 minutes 7. Dangerous mechanism (pedestrian struck by motor vehicle, occupant ejected from motor vehicle, fall from elevation > ft or 5 stairs) "Minor head injury" is defined as witnessed loss of consciousness, definite amnesia, or witnessed disorientation in a patient with a G C S score of 13 to 15. The Canadian C T Head Rule is a methodologically sound, clinically useful, and highly sensitive prediction rule for detecting clinically important brain injuries. It is more specific than any previous tools, but could increase scan utilization in some centers (1). A larger validation study is currently underway to ensure the results are reproducible. The C T Head Rule is being increasingly used through Europe and North America, with independent evaluations being conducted at various hospitals (1,9,10,13,14). The Canadian C T Head Rule has recently been compared to the N e w Orleans Criteria (NOC) for patients with minor head injury and G C S score of 15. The C T Head Rule and the New Orleans Criteria have equivalent high sensitivities for need for neurosurgical intervention and clinically important brain injury, but the head rule has higher specificity 6 for important clinical outcomes than does the N O C , and its use may result in reduced imaging rates (31). The rural setting poses a challenge in the application of the Canadian C T Head Rule, as management of head injuries in this setting is complicated by several factors (15). Most rural towns do not have C T scanners, and therefore transfer is required to apply the C T Guidelines. Transfer is expensive, and can be dangerous from some remote locations, or in inclement weather. There is also added distress to the patient, who wi l l be transferred from his or her community and support network. Stiell (17) suggests that physicians working in smaller hospitals without C T scanners use the high-risk criteria to select cases requiring a mandatory C T scan; those with medium-risk criteria may be observed or sent for urgent C T (17). This suggestion has not been validated. In 2003, a head trauma guideline task force was formed to devise a reasonable approach to head injured patents in the rural and remote regions of Alaska (15). This guide was developed through a literature review and the experiences of 18 rural physicians from around the state. The guidelines are a consensus of the committee, and have not been validated with a clinical trial (15). The guidelines for the management o f minimal head injuries (GCS>14) in remote and rural Alaska are as follows (see Figure 1). With minimal head injury, patients over two years of age with a G C S of 15 and no history of loss of consciousness can be discharged without imaging to a competent observer. Head injury instructions should be provided. 7 The incidence of a surgical lesion in this group is reported to approach 0.8%. In mild head trauma in patients over 5 years of age with a G C S of 14, and no risk factors or in patients with a G C S of 15, a documented loss of consciousness and no other risk factors, there are a number of approaches. When a C T scan is available and the G C S is 14 a C T scan is appropriate. Patients with a G C S of 15 can be managed appropriately in several ways including C T scanning, observation under medical supervision or discharge with a competent observer. The decision needs to factor in the patient's social situation as well as local resources. When a C T scan is not available skull x-rays may be helpful in identifying a subset of patients with mild injuries who have a higher risk of deteriorating. Cl inical deterioration in patients with a G C S of 14-15 but no skull fracture has been reported in 0.2-0.7% of patients. In patients that do have a fracture present the deterioration rate is 3.2-10%) 9. Skul l x-rays may facilitate the identification of a subgroup of asymptomatic patients who have a small but real risk of clinical deterioration. If skull x-rays are done and a fracture is noted, the patient should have a C T scan. If there is no fracture identifiable or a skull x-ray is not obtained, the patients need to be observed. Patients with a G C S of 14 without a C T scan or skull x-ray need to be actively observed in a medical setting. Patients with a G C S of 15 can be observed in a medical setting or by a competent observer as an outpatient (15). Patient outcomes and transports have not yet been studied, nor have these guidelines been validated. 8 Figure 1. Alaska Trauma Head Guidelines Alaska Trauma Systems Guidelines Minor Head Trauma age > 2 years G C S 15 no history of LOC discharge without imaging to a competent observer wtih head injury instructions surgical lesion incidence 0.8% age > 5 years no risk factors consider skull xrays if skull fracture, CT; clinical deterioration 0.2-0.7& in patients with no skull fracture; 3.2-10% if skull fracture present G C S 14 CT, if available observe in a medical setting G C S 15 documented LOC CT, if available observe or discharge to a competent observer 9 The Whistler Diagnostic and Treatment Center provides a unique area to conduct head injury research. It is a rural town, with limited resources, yet deals with 23,000 patient visits annually. The trauma and acuity levels are higher than any other Diagnostic and Treatment Center in Brit ish Columbia, and are also higher than in many hospitals (12). A n intake review of the W H C C in 2003 (12) revealed that approximately 500 head injuries were treated. A s a C T scanner was not a diagnostic option, patients were transferred, observed or discharged. Outcomes of head injuries diagnosed at this facility have not been formally studied. With the limited resources, and high acuity and volume, Whistler provides an excellent opportunity to examine a large number of head injuries in a rural setting: 10 OBJECTIVES AND HYPOTHESES This study is a review of all the disposition of all head injuries seen at the Whistler Health Care Center in 2004. How many were transported to a center with a C T scanner? O f those who were not, who should have been according to the C T Head Guidelines? How many patients were transferred, without meeting C T head guideline criteria? With this project, we were able to examine whether the C T Head guidelines in the rural setting would increase or decrease the number of transfers. This review could be used to examine the practicality of the C T Head Guidelines in the rural setting. A t the W H C C in 2004, were the C T Head Guidelines applied? Would application of the guidelines increase or decrease the number of transfers required? Would it change the patients chosen for transfer? How many of the patients had medium risk criteria? How many had high risk? Results from this study could be applied to the design of a prospective cohort study, and a Rural Canadian C T Head Rule. This rule would benefit physicians with limited C T scan access to guide transfers to medical facilities that can provide C T scanning. It was hypothesized that retrospectively applying the Canadian C T Head Guidelines to the 2004 head injury patients at the Whistler Health Care Center would have increased the number of scans performed. 11 METHODS A retrospective chart review of head injury patients seen at the Whistler Health Care Diagnostic and Treatment Center in 2 0 0 4 was conducted. The Canadian C T Head Guidelines were applied to all cases. See Appendix 1 for data collection format. Population Patients presenting to the Whistler Health Care Center with the triage diagnosis of: head injury, loss of consciousness, trauma, concussion, neck injury or memory loss/ amnesia. Those patients' cl inic charts had inclusion and exclusion criteria applied. Inclusion criteria > blunt trauma to the head resulting in definite amnesia, witnessed loss o f consciousness or disorientation; > initial E D Glasgow Coma Score of > 13; and > injury within the past 2 4 hours Exclusion criteria r N > age <16 years > no history of trauma as the primary event > obvious penetrating skull injury or depressed fracture > acute focal neurological deficit > acute trauma with unstable vital signs 12 > seizure prior to E D assessment > bleeding disorder, or anticoagulant use > a return to the E D for reassessment of the same head injury > pregnancy Patients included in the study were stratified into medium and high-risk groups, as defined by the C T Head guidelines. Disposition of these patients was recorded. The investigation process reviewed charts selected for the study, patient demographics, included and excluded charts, mechanism of injury, patients with medium or high risk criteria, patients who met criteria who were then transferred, and other patients who were transferred. Statistics Calculation of sample population estimates in each group was performed, with a 95% confidence interval. Plus Four Confidence Intervals were used in populations close to 1 or 0. Two reviewers evaluated ten percent of charts, and K coefficient was used to correlate recorder agreement (proportion of potential agreement beyond chance). This calculation was done to determine i f this study would be repeatable by another reviewer. The W H C C study population demographics were compared with the Stiel l 's original study (17), using a T-test to compare means, and X 2 to compare proportions. A total of 516 charts, from 554 patient encounters (38 follow-ups), were reviewed from the 2004 year. 13 Limitations There are several limitations to the design of this study. In conducting a record review, it is expected that some cases wi l l be missed due to data coding inconsistencies (for case finding), as well as inability to locate some medical records. Other head injured patients that did not seek medical attention, would also have been missed; For the cases that are reviewed, patient consent had not been obtained for , follow-up; therefore outcome is limited as to whether or not a patient is transferred. In reviewing the chart, the recorder may have a different impression of the patient than the attending physician. Final ly, this data may not be detailed enough to apply the Canadian C T Head rule. Medical record review studies are retrospective data set studies using patient data where the research question is posed after the data has been collected, and therefore inherently flawed (6,19). In retrospective studies, a causal relationship cannot be determined. There are no universally accepted standards for conducting or reporting retrospective data, however, work is currently being donein this area (3). This study is a retrospective chart review. The privacy act and U B C ethics do not allow for patient follow-up unless consent has been obtained prior to patient contact. Since the charts and patients reviewed in this study did not sign prior consent, follow-up was not an approved component of the ethics application. 14 RESULTS Charts reviewed A list of all 2004 visits to the W H C C , with the admitting category of trauma or neurological was produced. This list was reviewed to identify all cases with the diagnosis of head injury, concussions, trauma, or another synonym. r Five hundred and sixteen charts (554 patient encounters) were identified. A l l charts were pulled from fi l ing by reception staff at the W H C C for subsequent review. Thirty-eight of the charts were follow-ups; therefore 554 patient encounters yielded 516 patient charts (see Table 2). Exclusion criteria (as defined above) were applied to all charts. There were 174 patients who were under the age of 16, all of whom had a history of trauma, one with a depressed skull fracture, one with an acute neurological deficit, one with unstable vital signs, 5 with a seizure prior to assessment, one on anticoagulants, and one pregnant. 15 Table 2. Cases Hav ing Exc lus ion Cr i te r ia Reason for exclusion Cases Transfers Pregnant 1 0 Seizure prior to assessment 5 1 L G H Return to clinic (38) 0 Age<16yrs 174 0 Not seen by M D 22 0 Acute neurological deficit 1 1 L G H Acute trauma/unstable vitals 1 0 Obvious penetrating skull injury/depressed fracture 1 l . L G H Bleeding disorder or anticoagulant use 1 0 Total 206 3 Upon completion of application of exclusion criteria, 310 charts remained. Next, inclusion criteria were applied. Inclusion criteria: 1) blunt trauma to the head resulting in definite amnesia, witnessed loss of consciousness or disorientation; 2) initial E D Glasgow Coma Score of > 13; and 3) injury within the past 24 hours 16 There were 99 charts that did not meet the inclusion criteria. Fifty-six patients did not have a history of amnesia, loss of consciousness, or disorientation; 5 patients had a Glasgow Coma Score of less than 13, and 38 had not had a head injury within the last 24 hours (see Table 3). Table 3. Cases Not Meeting Inclusion Criteria Reason Number Transfers No amnesia, L O C or disorientation 56 Patient with GCS<13 5 1 V G H , 2 L G H No head injury within 24 hrs 38 Total 99 3 After application of inclusion and exclusion criteria, 211 (40.8%) charts remained for review. (See tables 4 and 5) -> Table 4. Charts Not Meeting Criteria Not meeting inclusion criteria Having an exclusion criteria Total Number of Cases 99 206 305 17 Table 5. Included Char ts Excluded Included Total Number of cases 305 211 516 The Canadian C T Head Guidelines were then applied for medium and high-risk criteria. High-risk (for neurologic intervention): 1) G C S score <15 at 2 hours after injury 2) Suspected open or depressed skull fracture 3) Any sign of basal skull fracture a. Hemotympanum b. "Raccoon" eyes c. C S F otorrhea/rhinorrhea d. Battle's sign 4) Vomit ing >2 episodes 5) Age >65 years Medium-risk (for brain injury on C T scan): 6) Amnesia before impact >30 minutes 7) Dangerous mechanism a. Pedestrian struck by a motor vehicle 18 b. Occupant ejected from a motor vehicle c. Fal l from elevation >3 feet or 5 stairs O f the 211 charts without exclusion criteria, and meeting inclusion criteria, there were 9 patients with high risk, and 42 with medium risk. O f the 9 patients meeting high risk criteria for neurosurgical intervention, there were 2 patients with a GCS<15 at 2 hours, 3 with greater than 2 episodes of vomiting, and 4 over the age of 65. O f the 42 patients meeting medium risk for brain injury on C T scan, 10 had amnesia greater than 30 minutes prior to the incident and 32 had a dangerous mechanism. O f the 32, 30 fell from a height greater than 3 feet, and 2 were ejected from a motor vehicle. The patients meeting medium or high-risk criteria have a C T indicated, according to the Canadian C T Head Rule. O f the 51 who had a C T indicated in this review, 4 were transferred to a center with a C T scanner. Two of these patients had high-risk criteria, and 2 of them had medium risk criteria. O f the remaining 160, 9 were transferred to a center with a C T scanner, and 2 were sent to a community hospital for observation (see tables 6 and 7, and figure 2). 19 Table 6. Result Summary 516 charts 305 excluded 206 with exclusion criteria 99 without inclusion criteria 211 included 42 with medium risk* 40 discharged home 2 sent to a center with C T 9 with high risk* 7 discharged home 2 sent to a center with C T 160 no C T indicated 149 discharged home 2 sent to a center for observation 9 sent to a center with C T *medium and high-risk patients have C T indicated Table 7. Disposition Summary Total Patients Excluded Included Transferred 516 305 211 Total transferred: 13 4 with C T indicated 9 without C T indicated 20 Figure 2. Patient Disposit ion • Discharge • Observation • Center with CT HIGH MEDIUM LOW Table 8. Acui ty Levels Risk Level Lancet WHCC Difference (p<0.01) High 1% 4% 100% confidence Medium 8% 20% 100% confidence Table 9. Injury f rom Sport Lancet WHCC Difference ( pO .O l ) Percentage of Injury from Sport 16% 78% 100 % confidence 21 Patient Demographics and Recorder Agreement The mean patient age was 27.5 years (11), the age range was 16-71 years (note 174 cases under the age o f 16 excluded), and the proportion o f male patients was 73%. In the original study, the mean age was 38.7 years (18), the age range was 16-99, and 69% of the patients were men. With a T value of 14.16 (0.79), the ages between the 2 study groups were statistically significant. X 2 was used to compare proportions of male gender between the two groups. With a standard error of 2 (95% confidence interval), there was no statistically significant difference between genders in the two studies. As demonstrated in Tables 8 and 9, the W H C C had a statistically significant higher acuity level (100% C.I., p<0.01), as well as a greater number of injuries from sport (100%o C.I., p<0.01). Two different recorders reviewed ten percent of charts in order to correlate the proportion of potential agreement beyond chance. This correlation was found to be K=0.89. 22 DISCUSSION The application of the Canadian C T Head Guidelines in the setting without a C T scanner poses a challenge to the practitioner in that arranging a C T scan and transporting the patient to the appropriate facility can be complicated. In the rural setting, patients are often observed and discharged, whereas in a center with a scanner, a C T head is frequently performed. From the rural setting, the patient must leave his or her community and face the risks and costs of travel in order to carry out the prescribed Canadian guidelines, which have been developed in a tertiary-care setting. The Canadian C T Head Guidelines were designed to decrease the number of scans being done, reduce the number of cl inically important missed cases, and standardize care across the country (17). It was hypothesized that in the rural setting, application of the guidelines would increase the number of recommended scans. The Canadian C T Head rules were published in 2001, and most of the W H C C physicians were aware of these. The guidelines were not posted in the E D , nor determined to be the standard of care in that setting. Use of the guidelines varied with individual physicians. With the exception of one, all Whistler E R doctors are solely in Emergency Medicine Practice, half of whom hold a C C F P - E M certification, and the others whom have enough experience to be eligible to challenge the E M certification. When compared to other rural settings it is l ikely the Whistler physicians have more emergency medicine training and experience. The goal of this study was to see i f the guidelines, when retrospectively applied to a set of charts in the rural setting, changed the disposition of patients with minor head injury. This study was conducted on head injury charts at the Whistler Health Care Center because of an unusually large number of high acuity cases arising in a rural setting. A certificate of ethics approval was obtained from the University of Brit ish Columbia Clinical Research Ethics Board prior to collecting any patient information (Appendix 2). O f the 516 charts that were reviewed, 211 remained after application of inclusion and exclusion criteria. O f the 9 patients with high-risk criteria, 2 were sent to a center with a C T scanner, and 7 were discharged home. O f the 42 patients with medium risk criteria, 2 were referred to a center with a scanner, and 40 were sent home. In the 160 patients with minor head injury, which did not meet the " C T indicated" criteria, 9 were sent to a center with a scanner, 2 were sent for observation, and 149 were discharged home. Fifty-one patients would have been sent for a scan i f the guidelines had been followed, whereas only 13 were referred. There would have been 9 fewer scans in the "not indicated" group, and 47 more in the "indicated" group. It is not clear why, some patients with low risk were referred a center with a scanner. These results exemplify the need for standardization of head injury management in that some clinically important cases may have been missed, and some transfers for C T scans could have been avoided. O f note, there were 174 children under the age of sixteen identified in this study. Although the Canadian C T Head Guidelines do not make recommendations for this age group, another study is currently underway. The ' C A T C H ' study has been designed to 24 form the Canadian Pediatric C T Head Rule. Phase one of this study is underway, with 3014 head injured patients reviewed so far. Approval for the second phase of this study is pending. Current recommendations for the Pediatric C T Head Rule are that C T is only required for minor head injury in patients with any medium or high-risk findings. High risk findings in the pediatric group are an initial G C S score <15, suspected skull penetration or depressed skull fracture, lethargy on exam and irritability on exam. Medium risk criteria are any sign of a basal skull fracture, a large, boggy scalp hematoma, a fall from a height of greater or equal to 3 feet or greater or equal to 5 stairs and a decreased level of consciousness after assessment (32). The N E X U S II study is a multi-center, prospective, observational study of all blunt head trauma victims who had a C T as part of their E D evaluation. Cl inical ly important intracranial injuries were identified by seven N E X U S II risk criteria: (1) evidence of significant skull fracture; (2) altered level of alertness; (3) neurologic deficit; (4) persistent vomiting; (5) presence of scalp hematoma; (6) abnormal behavior; and (7) coagulopathy (43). A prospective cohort study in the rural setting, which includes ages under sixteen, should also be developed. Exclusion criteria in the C T head rule could limit the exclusions to a younger age group as current evidence suggests that the increased concern and risk for the development of solid tumors is predominantly in younger children (43). In a one year old, the radiation exposure is a magnitude higher than adults, and that pediatric C T would result in significantly increased lifetime radiation risk over adult C T , because of increased dose per milliampere-second, and increased lifetime risk per unit dose (44). For this reason, 25 there have been recommendations to reduce the tube current (radiation) based on patient weight (45). The National Research Counci l 's Committee on the Biological Effects of Ionizing Radiation has estimated that children less than 10 years of age are several times more sensitive to radiation that middle-aged adults (46). Because children have more rapidly dividing cells than adults and have longer life expectancy, the odds that children wi l l develop cancers from x-ray radiation may be significantly higher than in adults (47). Significant debate continues about the age where radiation dose equals that in adults. This is l ikely why the C T Head rule excludes the entire pediatric group, for which a separate set of guidelines are being created. Had the pediatric age group been studied at W H C C , the number of subjects in this review i would have been close to 400, thus increasing its power and utility. In contrast to the current practice in the pediatric group, a study completed this fall examined a different method of managing pediatric head injury in the United Kingdom. In the U.K., approximately 500,000 children present to the emergency department with a head injury, and about 50,000 are admitted. The death rate is 5.3 per 100,000 children. This study compares management of a minor head injury with either immediate computed tomography for triage inpatient admission. Early discharge after immediate computed tomography had the same recovery at three months, no later complications, and equivalent patient satisfaction. It was also less costly than inpatient observation (35). This study was done in a center with a C T on site. 26 Overall, application of the C T Head guidelines to W H C C 2004 head injury charts would have increased the total number of patients transferred for a scan by four times, with a thirteen fold increase in the " C T indicated" group. It would, however, have decreased the number of scans performed in the "not-indicated" group by nine (see Table 5). In the literature, there are no clear guidelines as to the proper disposition of head injured patients in the rural setting. In the Canadian C T Head Rule for patients with minor head injury Stiell et al. (17) suggest that physicians working in smaller hospitals without C T scanners use the high risk criteria to select cases requiring a mandatory C T scan and those with medium-risk criteria be observed or sent for urgent C T . This suggestion is an expert opinion, and was not based on clinical outcome data. If Stiell 's rural suggestion (17) was followed, 9 (4%) of the 211 reviewed charts would have required a mandatory C T scan, and 42 (20%) would have been observed or sent for an urgent CT . This would increase the number of C T referrals from the W H C C , whether just the high, or both the high and medium risk patients were sent for CT . See Figure 3 for comparison of the W H C C outcomes and the hypothetical outcomes had the rule had been applied. 27 Figure 3. Compar ison of Outcomes The following details the patients selected for transfer for CT scan. The two in the high- risk group continued to have a GCS score of <15 at 2 hours after injury. Of the 2 transferred from the medium risk group, one had amnesia before impact >30 minutes, and the other was a multi-trauma. The transfer in the 'no CT indicated' group included 2 multi-traumas. The rationale for the referral of the other 7 in this group was not apparent from the medical record. As Shell's Lancet guidelines are currently the gold standard for head CT clinical decision-making in Canada, the application of his suggestion for the rural setting would change the practice of the physicians at the Whistler Health Care Center. Overall, more patients would be referred, however, there would be a decrease in the referral of the 'no CT indicated' cohort. 28 Transferring patients from Whistler to Vancouver for C T scan may not improve patient care. There is an inherent risk with Emergency transport, particularly in poor weather and road conditions. Transport has risk, as well as significant expense, with a cost of $3120 by air, or $500 by ambulance (36). At the end of the investigations, patients are left over 100 km from home, with no return transport. In addition to the cost and risk of transport, the C T scan itself is hot without risk. A C T Head has approximately the same amount of radiation as 150 chest X-Rays (29). The cost of a head C T scan ranges from $330 to $460, whereas hospital observation costs range from $700 to $990 (42). The price of a C T scanner is approximately $970,000, with $400,000 per year in operating costs (42). The current estimated cost of rehabilitation from a significant brain injury is 4 mil l ion dollars per patient, and one < estimate of the "cost of death" is 3.1 mil l ion dollars (42). The cost of scanning, as well as the cost of missing a case must both be considered when performing a future cost-benefit analysis. When comparing cost of C T and cost of observation overnight, a C T scan is cheaper. W H C C patients (with the exception of two) were sent home, so the overnight admission was negligible. W H C C likely saved money with its management of 2004 head injuries. The Canadian C T Head rule was designed to increase the sensitivity and specificity of detection of important minor head injuries. It was also designed with the intentions of decreasing the number of scans performed by 25-50% (17). A study of the impact of the guidelines on Brit ish management of E D head injuries found that the Canadian C T Head 29 Rule would result in an increase in the number of scans requested for minor head injuries, and an increase in cost (33). Reviewing one year's charts from Whistler, there would have been an overall increase of 400 percent in C T scans in minor head injury patients, had the C T Head Guidelines been applied. Util ization of the rule, however, could have decreased scans in the low risk group. Overall, the Canadian C T Head Guidelines may be too inclusive for the rural population. Preliminary recommendations, requiring validation, are as follows: do not transfer the low risk group for C T ; always transfer the high risk group for C T ; use clinical judgment in the medium risk group with the options of transfer for C T , observation or discharge to an appropriate care giver. There was a significant difference between the W H C C population, and the population in Shell 's article. In Whistler, 78% of the head injuries were from sport, as compared to 16% (derived from the combination of the bike, sport and contact sport categories). The proportions of these groups were significantly different, with a 100% confidence level (pO.01). Whistler patients also had a higher acuity level. The W H C C population had 4%> in the high-risk group, and 20% in the medium risk group, compared to the Lancet article with 1% and 8%, respectively. The proportions in both the high and medium risk groups in the W H C C study, as compared to the Lancet article (17) were both statistically significantly different, with 100% confidence (p<0.01). 30 Of the 211 patients meeting inclusion and exclusion criteria, 45 were skiing, 93 were snowboarding, 4 were skateboarding and 48 were cycling. O f the other 21 ,9 were involved in altercations, 7 had falls while intoxicated, and 5 had other falls. Mechanism of injury in sport varies depending on the nature of the sport, the use of protective equipment, and the expertise level of the participant. The W H C C study had a significantly higher proportion of sport related injury when compared to the original article, as well as a higher acuity level. As most of these sport related injuries occurred on the ski hi l l or in the mountain bike park, the mechanisms of injury are l ikely quite different from those sport injuries that were included in the original article. For this reason, a study that would better represent the rural population would have to include other communities. Alternatively, i f there were to be a rule created purely with the W H C C data, it would be specifically for a similar environment. A third phase of Stiell 's study is underway. Phase I of the study successfully derived the rule, and phase II confirmed the accuracy and safety of the rule. Phase III is designed to examine the actual change of behavior of physician, and is designed to study the effectiveness and safety of an active strategy to implement the Canadian C T Head Rule into practice. The objectives are to: 1) Determine clinical impact by comparing the intervention and control sites for: a) C T Head ordering rates, b) Missed neurological intervention cases, c) Missed brain injuries, d) Number of deaths, d) Length of stay in E D , and e) Patient satisfaction; 2) Determine sustainability of the impact; 3) Evaluate performance of the Canadian C T Head Rule (B). A similar study in the rural setting 31 would be of great value in comparing risk and benefit with the given transport risks and costs. The Canadian C T rules are now more publicly accepted and studied as compared to 2004. Util ization of the rule would have probably increased since that time. In order to evaluate the current practice of the W H C C group, a utilization study similar to Stiell 's current project could be done at Whistler (34). A study of the effect of a rural C T scanner on local health care in Walkerton, Ontario was published last month (37). This community of approximately 5000 people is 160 km away from a tertiary care setting, and 70 km from a secondary center. A pilot project was held to study the effect a rural C T would have on local heath care. It was found that C T improved local health care in that physicians were able to reach diagnoses more quickly, initiate treatment sooner, and make better-directed referrals to specialists. Patient satisfaction was also improved—rural patients want to be cared for in a rural ' environment. C T scanning rates in the rural setting grew closer to, but did not exceed the rates of scanning in the urban setting (37). A n independent review of the costs and revenue found that the scanner did not affect the hospital's resources negatively (37). This pilot study was concluded early, and a C T scanner fully authorized by the Ministry because of significant improvement in the area's health care (37). Having a scanner in Whistler would improve patient care with early diagnosis, treatments, and timely appropriate referrals. It would eliminate the risk and cost of 3 2 transport in those without significant brain injury on C T , and improve patient satisfaction of their care. A cost analysis would be required to determine whether a scanner in Whistler would reduce overall health care costs. Further study needs to be done to better understand the challenges and limitations of diagnostic imaging in the rural setting, particularly after traumatic brain injury. In order to design a clinical decision-making rule for the setting without a C T scanner, a prospective study in a similar setting should be performed. Based on evidence from Stiell et al. (17), it is reasonable to send all high-risk patients for C T . The moderate risk group, however, would benefit from a further assessment of guidelines, examining clinical outcomes, as well as cost and risk of travel. In such a prospective cohort study, patient consent would be obtained for inclusion in the study, consent for follow-up of symptoms, medical charts, C T results, interventions and outcomes. The future study would thus allow for detailed follow-up. Data would be recorded from the initial patient presentation, history and physical examination. As in the Stiell study (17), questions from history would be age, gender, arrival by ambulance, witnessed loss of consciousness (LOC) , duration of L O C , amnesia, headache, suspected chronic alcohol use, repeated vomiting, serum ethanol level, mechanism of injury/ sport, use of helmet, use of seatbelt. Data obtained from physical exam would include initial G C S , deterioration in G C S , pupils equal and reactive, lateralizing motor weakness, possible open skull fracture, sign of basal skull fracture, intoxication (drug or alcohol), object recall, seizure in emergency department. Patient management and outcomes 33 would then be recorded. These outcomes would be whether imaging was done (head C T or skull radiographs), and follow-up of cases for sequelae. Findings on history and physical would be correlated by stepwise logistic regression analysis to predict clinically important brain injury (16), as was done in the Stiell article to create the Canadian C T Head Rule (17). Other outcomes from'the rural setting would be distance, method and cost of transport, negative outcomes during transport, and costs of medical care in the receiving facility. In the design of the Lancet study, the priori sample size was estimated to be 2500 patients based upon the desired precision of 100% sensitivity for cl inically important brain injury with"a 95% confidence interval (17).. Theoretically, a similar number would be required in a rural setting study. Because of the higher incidence of the high and medium risk groups in the Whistler settings a smaller ' N ' would be required, calculated to be 813, based on incidence proportions relative to Shell 's study (17). \ The goal of this study would be to create a template for a multi-center study, from which a rural C T head rule could be developed, and published for the use of all rural 1 practitioners in Canada. The goal would be to create an equivalent to the "Ottawa Ankle Rules" for C T Head in the rural setting. The Ottawa ankle rules have been extensively studied, and have been shown to decrease ankle radiography by emergency physicians from 82.1%o to 61.6%; (P < 0.001); and by family physicians from 84.3% to 60.1%; (P < 0.001) (38). When the Ottawa ankle rules 34 were implemented in a study setting, there was a decrease in use of ankle radiography, waiting times, and costs without patient dissatisfaction or missed fractures (40). Despite the cost of missed fractures (including litigation costs), the Ottawa ankle rules would result in significant savings of health care dollars (39). Although this clinical guideline is widely, accepted, this does not always cause a change in physician behavior. Despite physician knowledge of the Ottawa Ankle Rules, in a review of actual cl inical practice, with there was no reduction in ankle radiography (41). Recommendations Unti l more conclusive evidence exists, it is recommended that all patients with minor head injury meeting the high-risk criteria be referred for mandatory C T . Those patients with medium risk criteria, should be considered for C T , or held for observation. Finally, it is recommended that all patients with any form of head injury be discharged to a reliable caregiver, and have early follow-up arranged for reassessment. The proposed 'Rural Canadian C T Head Guidelines' are illustrated below in Figure 4. 35 Figure 4. R u r a l Canad ian C T Head Guidel ines HEAD INJURY (within last 24h) blunt trauma with amnesia, LOC or disorientation GCS > 13 no exclusion criteria HIGH RISK GCS<15@2h post injury skull # (open/depressed/basal) vomiting >2x, age >65 MEDIUM RISK amnesia >30min before impact dangerous mechanism LOW RISK no high or medium risk criteria CT HEAD TRANSPORT CTHEAD TRANSPORT DISCHARGE The implications of this research have already reached the global and local community. Results were published in the Canadian Journal of Emergency Medicine in May 2006, and presented at the International Congress of Emergency Medicine in June 2006. On November 1, 2006, the Whistler Health Care Foundation announced the start of a campaign to raise two mi l l ion dollars to purchase and install a C T scanner at the W H C C . 36 BIBLIOGRAPHY 1. Boyle A , Santaruis L, Maimaris C. Evaluation of the impact of the Canadian C T Head Rule on Brit ish practice. Emergency Medicine Journal 2004; 21: 426-428. 2. Bulger E M , Nathens A B , Rivara FP. Management of severe head injury: institutional variations in care and effect on outcome. Crit ical Care Medicine 2002; 30(8): 1870-6. 3. Cleve P, Worster A . Reassessing the Methods of Medical Record Review Studies in Emergency Medicine Research. Unpublished 2005. 4. Committee on Trauma, American College of Surgeons. Advanced Trauma Life Support for Doctors. 6th edition, 1997. 5. Dunning J , Batchelor J , Stratford-Smith P, Teece S, Browns J , Sharpin C, Mackway-Jones K. A meta-analysis o f variables that predict significant intracranial injury in minor head trauma. Archives of Disease in Childhood 2004; 89(7)593-4. 6. Gilbert E H , Lowenstein SR, Kozo i l -McLa in J , Barta D C , Steiner J . Chart reviews in emergency medicine research: where are the methods?^ Annals of Emergency ' Medic inel996; 27(3): 305-8. 7. Hassan Z , Litt lewood S, Boamra O. The Impact o f the N I C E Head Injury Guidelines on Imaging and Admission. Trauma Audit and Research Network, Halford Royal Hospital 2004. 8. Hay del M J , Preston C A , M i l l s TJ. Indications for computer tomography in patients with minor head injury. New England Journal of Medicine 2000; 343(2): 100-5. 9. Ingebrigtsen T, Romner B, Kock-Jensen C. Scandinavian Guidelines for initial management of minimal mi ld and moderate head injuries. Journal of Trauma 2000; 48: 760-766. 10. Jones N R , Mo l loy C J , Kloeden C N , North J B , Simpson D A . Extradural haematoma: trends in outcome over 35 years. Brit ish Journal of Neurosurgery 1993; 7(5): 465-71. 11. Mi l le r E G , Holmes JF, Derlet R W . Uti l iz ing clinical factors to reduce head C T scan ordering for minor head trauma patients. Emergency Medicine Journal 1997; 15: 453-7 / 37 V 12. Mohr B. Head injured patients in the Whistler Health Care Center. Independent review 2003. Unpublished. 13. Mul ler K, Waterloo K, Romner B, Wester K, Ingebrigtsen T. M i l d head injuries: impact of a national strategy for implementation of management guidelines. Journal of Trauma 2003. 55(6): 1029-34. 14. Reinus W R , Zwemer F L . Cl inical prediction of emergency cranial computed tomography results. Annals of Emergency Medic inel994; 23(6): 1271-8. 15. Sacco F., Zafren K, Brown K. Alaska head trauma guidelines. Alaska Trauma Systems Review Committee 2003. 16. Stiell IG, Lesiuk H , Wells G A . The Canadian C T Head Rule study for patients with minor head injury: rationale, objectives, and methodology for phase I. Annals o f Emergency Medicine 2001; 38(2): 160-9. 17. Stiell IG, Wells, G A , Vandemheen K. The Canadian C T Head Rule for patients with minor head injury. Lancet 2001; 357:1391-96. 18. Stiell IG, Lesiuk H, Wells G A , Coyle D, McKnight R D . Canadian C T Head Rule study for patients with minor head injury: methodology for phase II (validation and economic analysis). Annals of Emergency Medicine 2001; 38(3): 317-22. 19. Tintinelli J E , Kelen G D , Stapczynski JS. Emergency medicine: a comprehensive study guide, 4th edition. McGraw-H i l l 2000. 20. Worster A , Haines T. Advanced Statistics: Understanding medical record review studies. Academic Emergency Medicine 2004; 11: 187-92. 21. Bailes J E , Cantu R C . Head injury in athletes. Neurosurgery 2001; 48(1): 26-45. 22. Cantu R C . Athletic head injuries. Clinics in Sports Medicine 1997; 16(3): 531-42. 23. Cooper M T , McGee K M , Anderson D G , Epidemiology of athletic head and neck injuries. Cl inics in Sports Medicine 2003; 22(3): 427-43. 24. Dias M S . , Traumatic brain and spinal cord injury. Pediatric Cl inics of North America 2004; 51(2). 25. Johnston K M , Ptito A , Chankowsky J , Chen J K . New frontiers in diagnostic imaging in concussive head injury. Cl inical Journal of Sport Medicine 2001; 11(3): 166-75. 38 26. Johnston K M , Lassonde M , Ptito A . A contemporary neurosurgical approach to sport-related head injury: the M c G i l l concussion protocol. Journal of the American College of Surgeons 2001; 192(4). 27. Kel ly K D , Lissel H L , Rowe B H , Vincenten J A , Voaklander D C . Sport and recreation-related head injuries treated in the emergency department. Cl inical Journal of Sport Medicine 2001; 11(2):77-81. 28. Lovel l M , Col l ins M , Bradley J. Return to play following sports-related concussion. Cl inics in Sports Medicine 2004; 23(3). 29. Poirier M P . Concussions: assessment, management, and recommendations for return to activity. Cl inical Pediatric Emergency Medicine 2003; 4 (3). 30. Frush D P , Donnelly L F , Rosen N S . Computed tomography and radiation risks: what pediatric health care providers should know. Pediatrics 2003; 112(4):971-2. 31. Stiell IG, Clement C M , Rowe B H , Schull M J , Brison R, Cass D, Eisenhauer M A , McKnight R D , Bandiera G , Holroyd B, Lee JS, Dreyer J , Worthington JR, Reardon M , Greenberg G , Lesiuk H, MacPhai l I, Wells G A . Comparison of the Canadian C T Head Rule and the New Orleans Criteria in patients with minor head injury. Journal of the American Medical Association 2005; 294(12): 1511-8. 32. Dunning J , Batchelor J , Stratford-Smith P, Teece S, Browne J , Sharpin C, Mack- way-Jones J . A meta-analysis of variables that predict significant intracranial injury in minor head trauma. Archives of Disease in Childhood 2004; 89: 593- 594. 33. Boyle A , Santarius L, Maimaris C. Evaluation of the impact of the Canadian C T Head Rule on Brit ish practice. Journal of Emergency Medicine 2004; 21:426- 428. ' 34. Stiell I. Evaluation of an active strategy to implement the Canadian C T Head Rule: Phase III. Unpublished study protocol. 35. Marcovitch H. Managing minor head injury in children. Early discharge after computed tomography is safe and cost effective. Brit ish Medical Journal 2006; 333:455-456. 36. Brink B. Brit ish Columbia Ambulance Service. Personal correspondence. 37. Merkens B J , Mowbray R D , Creeden L, Engels PT, Rothwell D M , Chan B T B , Tu K. A rural C T scanner: evaluating the effect on local health care. Journal of the Canadian Association of Radiologists 2006; 57(4): 224-231. 39 38. Stiell I, Wel ls G , Laupacis A , Brison R, Verbeek R, Vandemheen K, Naylor D. A multi-centre trial to introduce clinical decision rules for the use of radiography in acute ankle injuries. Brit ish Medical Journal 1995; 311: 594-597. 39. Anis A H , Stiell IG, Steward D F , Laupacis A . Cost-effectiveness analysis of the Ottawa Ankle Rules. Annals of Emergency Medicine 1995; 26: 422-428. 40. Stiell IG, McKnight R D , Greenberg G H , McDowe l l I, Nair R C , Wells G A , Johns C, Worthington JR. Implementation of the Ottawa Ankle Rules. Journal of the American Medical Association 1994; 271: 827-832. 41. Cameron C, Naylor D. No impact from active dissemination of the Ottawa Ankle Rules: further evidence of the need for local implementation of practice guidelines. Canadian Medical Association Journal 1999; 160:1165-68. 42. Norlund A , Marke L A , Geijerstam JL , Oredsson S, Britton M . Immediate computed tomography or admission for observation after mild injury: cost comparison in randomized controlled trial. Brit ish Medical Journal 2006; 333:469. 43. Oman J A , Cooper R J , Holmes JF, Viccel l io P, Nyce A , Ross S E , Hoffma, JR, Mower W R . Performance of a decision rule to predict need for computed tomography among children with blunt head trauma. Pediatrics 2006; 117 (2). 44. Brenner D J , Ellsiton C D , Hal l E J , Berdon W E . Estimated risks of radiation- induced fatal cancer, from pediatric CT . American Journal of Roentgenology 2001; 176: 289-296. 45. Donnelly L F , Emery K H , Brody A S , Laor T, Gy lys-Mor in V M , Anton C G , Thomas SR, Frush DP . Min imiz ing radiation dose for pediatric body applications of single-detector helical CT . American Journal of Roentgenology. 2001; 176(2): 303-6. 46. Committee on the Biological Effects of Ionizing Radiations. Health effects of low levels of ionizing radiation. National Research Counci l 2001. 47. American College of Radiology. One size does not fit al l : reducing risks from Pediatric C T . American College of Radiology Bulletin 2001; 57 (2): 20-23. 40 A P P E N D I X 1: D A T A C O L L E C T I O N S H E E T Chart number Date of admission • any exclusion criteria? If so, stop now. -age <16 years -no history of trauma as the primary event -obvious penetrating skull injury or depressed fracture -acute focal neurological deficit -acute trauma with unstable vital signs -seizure prior to E D assessment -bleeding disorder, or anticoagulant use -a return to the E D for reassessment of the same head injury -pregnancy • inclusion criteria met? If not, stop now. -blunt trauma to the head resulting in definite amnesia, witnessed loss of consciousness or disorientation; -initial E D Glasgow Coma Score of > 13; and -injury within the past 24 hours • GCS score <15 at 2 hours after injury, • suspected open or depressed skull fracture, • any sign of basal skull fracture (battles, otorrhea, rhinorrhea, raccoon), • vomiting >2 episodes or • age >65 years • amnesia before impact >30 minutes, or a • dangerous mechanism • pedestrian struck by a motor vehicle, • occupant ejected from a motor vehicle, or a • fall from >3 feet or 5 stairs Transferred? • no • time in ER: admission discharge • yes • LGH • VGH • St Pauls • Squamish • other 41


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