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The Role of Neuroimaging in the Initial Management of Patients With Minor Head Injury
ORIGINAL CONTRIBUTION
The Role of Neuroimaging in the Initial Management of Patients With Minor Head Injury From the Departments of Orthopaedic Surgery* and Neurosurgery, University Hospital, Copenhagen County Hospital, Glostrup, Denmark. Receivedfor publication August 23, 1993. Revisionsreceived September26 and November29, 1993. Acceptedfor publication December 15, 1993. This study was supported by the DirectorJacob Madsen and Wife Olga Madsen Foundation.
Benn R Duus, MD* Bjern Lind, MD* Hanne Christensen,MD* Ole A Nielsen, MDt
Study objective: To determine whether omitting neuroimaglng in the primary assessment of patients with minor head injuries in the emergency department is safe.
Design: Prospective cohort study,
Setting: University hospital, Copenhagen County Hospital, Glostrup, Denmark. Participants: The study group consisted of 2,204 patients presenting to the ED after sustaining minor head injuries. Only patients able to talk and walk were included. Measurements and main results: The decision to admit was based exclusively on clinical guidelines in which the findings in the ED were of highest priority. Seven patients (0.3%) had a skull radiograph; computed tomography was not used in the primary evaluation. Four hundred thirty patients (19.5%) were admitted. After hospitalization, four patients developed intracranial complicationsl One required surgery, two required hyerventilation, and one was observed. Follow-up demonstrated that no patient with an intracranial complication had been missed.
Conclusion: We found it safe to exclude neuroimaging in the primary assessment of patients with minor head injuries in the ED, and to rely instead on clinical criteria. [Duus 8R, Lind B, Christensen H, Nielsen OA: The role of neuroimaging in the initial management of patients with minor head injury. Ann EmergMedJune 1994;23:1279-1283.]
JUNE 1994 23:6 ANNALS OF EMERGENCY MEDICINE
1279
NEUROIMAGING Duus et al
INTRODUCTION The decision to admit or send home patients who have sustained minor head injury has always been a difficult clinical challenge. In the search for aids to assist in this judgment, the routine use of skull radiographs has been advocated.} ,2 Klauber et aP generated the hypothesis that the most important factor in the treatment of head injury was to make the correct diagnosis in low-risk patients as early as possible. This has led traumatologists to investigate and advocate the use of routine computed tomography (CT) scanning in the primary evaluation of patients with minor head injury to the emergency department. 4-6 Even under the present medicolegal climate in the United states, a 1991 editorial challenged this tendency toward defensive medicine.r The author stressed that the application of good clinical skills still has an appropriate place in the management of patients with minor head injuries. The author called for study of the careful use of neurosurgical examinations, including sequential observation, and for adding neuroimaging only in selected patients. We performed a prospective cohort study on patients with minor head injuries. The purpose was to determine whether it was safe to rely on the clinical examination in the ED and omit neuroimaging in deciding which patients to admit.
MATERIALS AND METHODS The study unit was a suburban university hospital situated in a community with large industries and with a large indigent population. The hospital serves a population of 179,900, and the ED census was 44,297 patients in 1990. The ED is staffed by junior physicians with one to three
Figure. Guidelines for admission used by the ED physician 1, Confusion or aggression on ED examination 2. Impaired consciousness or unconsciousness in ED 3, Focal neurologic signs 4, Skull fracture suspected on the basis of clinical findings 5, Alcohol intoxication or other medical condition that interferes with assessment, when mental status does not improve after several hours of observation 6, History of convulsions 7, Amnesia for more than 15 minutes 8, History of unconsciousness for more than 15 minutes witnessed by a competent observer 9, Children age 3 years or less with symptoms such as headache and vomiting 10. No responsible adult available at home for observation
128B
years of clinical experience who rotate through the department. All consecutive patients presenting to the ED after minor head injury between the March 1, 1990, and February 28, 1991, who were able to talk and walk were included in the study. This definition included patients with cognitive dysfunction and unclear speech, but not those who were comatose, unable to identify themselves, or unresponsive to pain. Informed consent was obtained and a head injury sheet was filled out by the ED physician. Epidemiological findings, including the cause of the accident; symptoms; history; and clinical findings such as alertness, signs of alcohol intoxication, and positive neurologic findings, were recorded. Patients exhibiting one or more of the characteristics in the figure were admitted. The ED physicians were instructed in writing that skull radiographs should not be used in deciding whether to admit a patient. Patients discharged from the ED were provided with an information sheet which emphasized that they should return immediately if they developed increasing apathy, unusual behavior, increasing headache, repeated vomiting, or seizures. Patients who were hospitalized were referred to and observed in the orthopedic, neurosurgical, or pediatric department on the basis of a predetermined schedule. Patients who deteriorated during the hospital stay were evaluated by a neurosurgeon, and a CT scan was performed if necessa~ The decision to perform a CT scan was based on a decline in the level of consciousness and/or the appearance of positive neurologic signs. No specific set of guidelines was used. One year later, data on all patients with any discharge diagnosis during the study period and up to two months later that corresponded to International Classification of Diseases (ICD) codes 851.00 through 854.99 were drawn from the National Danish Patient Register. These ICD codes cover cerebral laceration and contusion (851.00 through 851.99); traumatic epidural, subdural, or subarachnoidal hemorrhage (852.00 through 852.99); other intracranial hemorrhages (853.00 through 853.99); and other intracranial lesions (854.00 through 854.99). Data with the same ICD codes also were drawn from the Danish Cause of Death Register, which covers deaths inside and outside hospitals and other health care facilities. These data were compared to our records to determine if any of our patients had been admitted later because of an intracranial complication to the minor head injury or had died outside the hospital because of an intracranial complication.
ANNALS OF EMERGENCY MEDICINE
23:6
JUNE 1994
NEUROIMAGING
Duus et aI
The Z2 test and the Kruskall-Wallis test were used to compare groups. RESULTS
A total of 1,378 men and 826 women, with a mean age of 23.7 years (range, 0 to 108 years), were included in the study; 430 (19.5%) were admitted. The admission rate was as follows: 12.2% were less than 15 years old, 24.2% were between 15 and 64 years old, and 33.6% were more than 64 years old (P < .0001, Z2 test). Even though physicians were instructed not to use skull radiographs, seven patients (0.3%) had a skull radiograph. One patient had a fracture, but did not develop any intracranial complications. Twenty-one patients hospitalized according to clinical guidelines had CT scans. Nine patients were normal; old lesions, such as infarction or atrophy, were found in six, in two, a fracture without any intracranial lesion was diagnosed, and an intracranial hemorrhage was found in four patients. In all, 1% of patients presenting to the ED had a CT scan. Magnetic resonance imaging was not used. Thirty-eight patients had radiographs of the face; eight demonstrated a fracture. Forty-two patients had radiographs of the cervical spine; two showed fracture, and both were hospitalized. The four patients who developed an intracranial complication were identified within the first hour after arrival in the ED. All provided adequate answers to questions initially, but within two hours the level of consciousness declined, and a CT scan was performed. The scan revealed an epidural hematoma in one patient who had a craniotomy and brain contusion, and edema in two patients who required intracranial pressure monitoring and hyperventilation. One of these patients was treated with mannitol but died because of intractable brain edema. The last patient had a skull fracture and minor contusions with bleedings and surrounding edema. This patient received no specific treatment other than observation and tranquilizers. Our data were compared with those collected from the National Danish Patient Register and the Danish Cause of Death Register. None of our patients who were discharged immediately without hospitalization were later discharged from a hospital in Denmark under a diagnosis indicating an intracranial complication or died outside the hospital because of an intracranial complication. The mean length of hospitalization was 1.2 days (range, 1 to 7 days) in children, 1.4 days (range, 1 to 12 days) in adults, and 3.2 days (range, 1 to 39 days) in the elderly (P < .0001, Kruskall-Wallis tes0. The long hospitalization time for elderly patients was due to social problems, such as the patient not being able to live alone, and
JUNE 1994 23:6 ANNALS OF EMERGENCYMEDICINE
the need for training in some of the elderly patients before discharge. The Table shows each criterion that was cause for admission. Two hundred fifty (58%) of the hospitalized patients fulfilled multiple guideline criteria. Thirty patients (7.0%) were hospitalized even though none of the guideline criteria were met. Twenty-eight of these patients had one or more of the following symptoms: severe headache, vomiting, amnesia for less than 15 minutes, or unconsciousness for less than 15 minutes. In two cases, no information was provided on these items. DISCUSSION
The use of imaging after minor head injury was the subject of major controversy throughout the 1980s. In 1980, Masters s concluded that skull films alone seldom indicate more serious internal head injury, and he found no skull films to be effective contributors to evaluation, management, or prognosis of outcome after head trauma. Nevertheless, the discussion continued, and numerous studies on the value of skull radiographs in the evaluation of minor head injuries have been performed since. 9-15 Differences of opinion exist between radiologists, who say that skull radiographs are expensive and have a very low yield,11,13 and neurosurgeons, who recommend skull radiographs for all patients who sustain a head injury, minor or major. 1,2 Other neurosurgeons 1~ have concluded that skull radiographs should not be used to determine the need for hospital admission. In 1987, an American muhidisciplinary panel recommended an approach based on the distnbution of the patients in low-risk, moderate-risk, and high-risk groups. Only in the moderate-risk group was skull radiograph Table.
Number of patients in whom each criterion was the exclusive cause for admission Criterion
Confusion or aggression Impaired consciousness Neurologic signs Suspected skull fracture Alcohol intoxication Convulsions Amnesia for more than 15 minutes Unconsciousfor more than 15 minutes Age less than 3 years No responsible person in the home
No of Patients (%)
11 (2.6) 43 (10.g) 15 (3.5) 8 (1.9) 21 (4.9) 6 (1.4) 16 (3.7) 1 (0.2) 11 (2.6) 18 (4.2)
1281
NEUROIMAGING Duus et al
indicated, and then only rarely. 9 Feuerman et al > found no benefit from the use of skull radiographs and concluded that the neurologic examination, including the Glasgow Coma Scale score and evaluation Of mental status, was the best predictor of intracranial complications after minor head injuries. Correspondingly, de Lacey et a1.3 emphasized that loose and liberal policies on skull radiographs be abandoned. Recently, a retrospective Scandinavian study of 1,876 patients found no justification for skull radiographs after minor head injuries. 15 There is no doubt that a considerable portion of the skull radiographs in the ED are obtained for medicolegal reasons. 12 Authors have stressed that it is the ED physician who runs the risk of a charge of negligence if a patient is discharged without a skull radiograph and later develops an intracranial complication. 16 Thus, it is essential to reliably predict the outcome after minor head injuries. The increased use of technology and the risk of malpractice lawsuits have resulted in the use of more refined diagnostic tests, even in patients with trivial minor head injuries. Recently, American traumatologists have recommended the use of CT scanning to determine which patients to discharge from the ED after a minor head injury. 4-<1r Magnetic resonance imaging after minor head injury has identified anatomic lesions in 10% of these patients discharged from the ED. The clinical consequence of these findings has been questioned) 8 The medical malpractice lawsuit is a very rare phenomenon in Scandinavia. This led to our being able to base this study on the clinical admission guidelines generated in a retrospective study, t ~ as well as o~er studies.l,8,2~ In developing our guidelines, we stressed the importance of the findings in the ED (Figure, first five items). The symptoms from the history (Figure, fifth through eighth items) were an indication for hospitalization only if they were very pronounced, ie, amnesia and witnessed unconsciousness for more than 15 minutes. This is emphasized by the finding that only 16 patient s and one patient, respectively, were admitted with one of these criteria as the exclusive cause. EDs are staffed by junior physicians with limited clinical experience. [t is well known that skull radiographs are difficult to evaluate. Thitlainayagam et a122 found a positivepredictive value of skull fracture found by ED physicians of only 0.59; the negative-predictive value was 0.99. Furthermore, skull radiographs done in the ED are very often of unsatisfactory quality, especially in uncooperative patients. 15 If the guidelines for skull radiograph published by a group of neurosurgeons t had been adopted for use in our
1 2 82
study, at least 689 skull radiographs should have been taken in the ED during the study period. Extrapolating these figures to the entire nation of Denmark, at least 21,000 skull radiographs after minor head injury would be obtained each year. We explicitly abandoned the use of skull radiographs in our study. Instead, we used clinicat guidelines as determinants of admission. No patient was discharged and had subsequent hospitalization because of intracranial complications related to minor head injury. In retrospect, only four patients needed treatment. Thus, one Can question whether it was necessary to admit the remaining 426 patients. However, we do not believe that the clinical situation in the ED would permit us to send more Patients home than we did in this study. To further elucidate the problems concerning the primary treatment of patients with minor head injuries, we will continue the data collection. CONCLUSION
The use of guidelines based primarily on the clinical findings in the ED allows the safe primary evaluation of patients with minor head injuries. The ED physician does not need skull radiographs or other neuroimaging methods to decide which patients to admit. REFERENCES 1. Guidelines for initial management after head injury in adults. Suggestions from a group of neurosurgeons. Br Mad J 1984;288:983-985. 2. Jennett B: Skull x-rays after mild head injuries. Arch EmergMed1987i4:133-135. 3. Klauber MR, Maishall LF, Luerssen T, et al: Determinants of head injury mortality: Importance of the low risk patient. Neurosurgery1989;24:31-36. 4. Stein SC, Ross SE: The value of computed tomographic scans in patients with low-risk head injuries. Neurosurgery1990;26:638-640. 5. Stein SCI O'Malley KF, Ross SEI Is routine computed tomography scanning too expensive for mild head injury? Ann EmergMad1991;20:1286-1289 6. Livingston DH, Loder PA, Koziol J, et al! The use of CT scanning to triage patients requiring admission following minimal head injury. J Trauma1991;31:483-487. 7. Pitts LH: The role ofneuroimaging in minor head injury. Ann EmergMed1991;2G:1387-1388 8. Masters SJ: Evaluation of head trauma: Efficacy of skull films. AJR1980;135:539-547. 9. Masters SJ, McClean PM, Arcarese JS, et al: Skull x-ray examinations after head trauma. Recommendations by a multidisciplinary panel and.validatio~ study. NEngtJMed1987;316:8491. 10. Cooper PR, He V: Role of emergency skull x-ray films in the evaluation of the head injured patient: A retrospective study. Neurosurgery1983;13:136-140. 11. Costs and benefits of skull radiography for head injury. A national study by the Royal College of Radiologists. Lancet1981 ;2:791-795. 12. Balasubramaniam S, Kapadia T, Campbell JA, et al: Efficacy of skull radiography. Am J Surg 1981 ;142:366-369: 13. de Lacey G, McCabe M, Constant O, et al: Testing a policy for skull radiography (and admission) following mild head injury. BrJRadie11990;63:14-18
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14. FeuermanT, Wackym PA, 6ade 6F, et al: Value of skull radiography,head computed tomographicscanning,and admissionfor observationin casesof minor head injury. Neurosurgery1988;22:449-453. 15. RosenornJ, Ouus B, Nielsen K, et al: Is a skull x-ray necessaryafter milder headtrauma? Br J Neurosurg1991;5:135-139. 16. Adams CR, Briggs M, PotterJM: Routineskull radiographyafter head injury. Lancet 1981;1:161. 17. HaradFT, Kerstein MD: Inadequacyof bedsideclinical indicators in identifying significant intracranial injury in trauma patients. J Trauma1992;32:359-361. 18. DoezemaD, King JN, TandbergD, et al: Magnetic resonanceimaging in minor head injury. Ann EmergMed 1991;20:1281-1285.
Copyright 9 by the A m e r i c a n College of E m e r g e n c y Physicians Reprint no. 47/1/55749
Address for reprints: BR Duus, MD Willemoesgade 39, 3.tv. Copenhagen 0, Denmark Fax +045 35 36 67 33
19. Duus BR, BoesenT, Kruse KV, et al: Prognosticsigns in the evaluation of patients with minor head injuries. BrJ Surg1993;80:988-991. 20. FowkesFG, EnnisWP, EvansRC, et al: Admission guidelinesfor head injuries: Variancewith clinical practice in accident and emergencyunits in the UK. BrJ Surg1986;73:891-893. 21. Weston PAM: Admissionpolicy for patients following headinjury. BrJSurg 1981;68:663-664. 22. ThillainayagamK, MacMillan R, Mendelow AD, et al: How accuratelyare fractures of the skull diagnosedin an accident and emergencydepartment.Injury1987;18:319-321.
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ANNALS OF EMER6ENCY MEDICINE
12 8 3
The Role of Neuroimaging in the Initial Management of Patients With Minor Head Injury From the Departments of Orthopaedic Surgery* and Neurosurgery, University Hospital, Copenhagen County Hospital, Glostrup, Denmark. Receivedfor publication August 23, 1993. Revisionsreceived September26 and November29, 1993. Acceptedfor publication December 15, 1993. This study was supported by the DirectorJacob Madsen and Wife Olga Madsen Foundation.
Benn R Duus, MD* Bjern Lind, MD* Hanne Christensen,MD* Ole A Nielsen, MDt
Study objective: To determine whether omitting neuroimaglng in the primary assessment of patients with minor head injuries in the emergency department is safe.
Design: Prospective cohort study,
Setting: University hospital, Copenhagen County Hospital, Glostrup, Denmark. Participants: The study group consisted of 2,204 patients presenting to the ED after sustaining minor head injuries. Only patients able to talk and walk were included. Measurements and main results: The decision to admit was based exclusively on clinical guidelines in which the findings in the ED were of highest priority. Seven patients (0.3%) had a skull radiograph; computed tomography was not used in the primary evaluation. Four hundred thirty patients (19.5%) were admitted. After hospitalization, four patients developed intracranial complicationsl One required surgery, two required hyerventilation, and one was observed. Follow-up demonstrated that no patient with an intracranial complication had been missed.
Conclusion: We found it safe to exclude neuroimaging in the primary assessment of patients with minor head injuries in the ED, and to rely instead on clinical criteria. [Duus 8R, Lind B, Christensen H, Nielsen OA: The role of neuroimaging in the initial management of patients with minor head injury. Ann EmergMedJune 1994;23:1279-1283.]
JUNE 1994 23:6 ANNALS OF EMERGENCY MEDICINE
1279
NEUROIMAGING Duus et al
INTRODUCTION The decision to admit or send home patients who have sustained minor head injury has always been a difficult clinical challenge. In the search for aids to assist in this judgment, the routine use of skull radiographs has been advocated.} ,2 Klauber et aP generated the hypothesis that the most important factor in the treatment of head injury was to make the correct diagnosis in low-risk patients as early as possible. This has led traumatologists to investigate and advocate the use of routine computed tomography (CT) scanning in the primary evaluation of patients with minor head injury to the emergency department. 4-6 Even under the present medicolegal climate in the United states, a 1991 editorial challenged this tendency toward defensive medicine.r The author stressed that the application of good clinical skills still has an appropriate place in the management of patients with minor head injuries. The author called for study of the careful use of neurosurgical examinations, including sequential observation, and for adding neuroimaging only in selected patients. We performed a prospective cohort study on patients with minor head injuries. The purpose was to determine whether it was safe to rely on the clinical examination in the ED and omit neuroimaging in deciding which patients to admit.
MATERIALS AND METHODS The study unit was a suburban university hospital situated in a community with large industries and with a large indigent population. The hospital serves a population of 179,900, and the ED census was 44,297 patients in 1990. The ED is staffed by junior physicians with one to three
Figure. Guidelines for admission used by the ED physician 1, Confusion or aggression on ED examination 2. Impaired consciousness or unconsciousness in ED 3, Focal neurologic signs 4, Skull fracture suspected on the basis of clinical findings 5, Alcohol intoxication or other medical condition that interferes with assessment, when mental status does not improve after several hours of observation 6, History of convulsions 7, Amnesia for more than 15 minutes 8, History of unconsciousness for more than 15 minutes witnessed by a competent observer 9, Children age 3 years or less with symptoms such as headache and vomiting 10. No responsible adult available at home for observation
128B
years of clinical experience who rotate through the department. All consecutive patients presenting to the ED after minor head injury between the March 1, 1990, and February 28, 1991, who were able to talk and walk were included in the study. This definition included patients with cognitive dysfunction and unclear speech, but not those who were comatose, unable to identify themselves, or unresponsive to pain. Informed consent was obtained and a head injury sheet was filled out by the ED physician. Epidemiological findings, including the cause of the accident; symptoms; history; and clinical findings such as alertness, signs of alcohol intoxication, and positive neurologic findings, were recorded. Patients exhibiting one or more of the characteristics in the figure were admitted. The ED physicians were instructed in writing that skull radiographs should not be used in deciding whether to admit a patient. Patients discharged from the ED were provided with an information sheet which emphasized that they should return immediately if they developed increasing apathy, unusual behavior, increasing headache, repeated vomiting, or seizures. Patients who were hospitalized were referred to and observed in the orthopedic, neurosurgical, or pediatric department on the basis of a predetermined schedule. Patients who deteriorated during the hospital stay were evaluated by a neurosurgeon, and a CT scan was performed if necessa~ The decision to perform a CT scan was based on a decline in the level of consciousness and/or the appearance of positive neurologic signs. No specific set of guidelines was used. One year later, data on all patients with any discharge diagnosis during the study period and up to two months later that corresponded to International Classification of Diseases (ICD) codes 851.00 through 854.99 were drawn from the National Danish Patient Register. These ICD codes cover cerebral laceration and contusion (851.00 through 851.99); traumatic epidural, subdural, or subarachnoidal hemorrhage (852.00 through 852.99); other intracranial hemorrhages (853.00 through 853.99); and other intracranial lesions (854.00 through 854.99). Data with the same ICD codes also were drawn from the Danish Cause of Death Register, which covers deaths inside and outside hospitals and other health care facilities. These data were compared to our records to determine if any of our patients had been admitted later because of an intracranial complication to the minor head injury or had died outside the hospital because of an intracranial complication.
ANNALS OF EMERGENCY MEDICINE
23:6
JUNE 1994
NEUROIMAGING
Duus et aI
The Z2 test and the Kruskall-Wallis test were used to compare groups. RESULTS
A total of 1,378 men and 826 women, with a mean age of 23.7 years (range, 0 to 108 years), were included in the study; 430 (19.5%) were admitted. The admission rate was as follows: 12.2% were less than 15 years old, 24.2% were between 15 and 64 years old, and 33.6% were more than 64 years old (P < .0001, Z2 test). Even though physicians were instructed not to use skull radiographs, seven patients (0.3%) had a skull radiograph. One patient had a fracture, but did not develop any intracranial complications. Twenty-one patients hospitalized according to clinical guidelines had CT scans. Nine patients were normal; old lesions, such as infarction or atrophy, were found in six, in two, a fracture without any intracranial lesion was diagnosed, and an intracranial hemorrhage was found in four patients. In all, 1% of patients presenting to the ED had a CT scan. Magnetic resonance imaging was not used. Thirty-eight patients had radiographs of the face; eight demonstrated a fracture. Forty-two patients had radiographs of the cervical spine; two showed fracture, and both were hospitalized. The four patients who developed an intracranial complication were identified within the first hour after arrival in the ED. All provided adequate answers to questions initially, but within two hours the level of consciousness declined, and a CT scan was performed. The scan revealed an epidural hematoma in one patient who had a craniotomy and brain contusion, and edema in two patients who required intracranial pressure monitoring and hyperventilation. One of these patients was treated with mannitol but died because of intractable brain edema. The last patient had a skull fracture and minor contusions with bleedings and surrounding edema. This patient received no specific treatment other than observation and tranquilizers. Our data were compared with those collected from the National Danish Patient Register and the Danish Cause of Death Register. None of our patients who were discharged immediately without hospitalization were later discharged from a hospital in Denmark under a diagnosis indicating an intracranial complication or died outside the hospital because of an intracranial complication. The mean length of hospitalization was 1.2 days (range, 1 to 7 days) in children, 1.4 days (range, 1 to 12 days) in adults, and 3.2 days (range, 1 to 39 days) in the elderly (P < .0001, Kruskall-Wallis tes0. The long hospitalization time for elderly patients was due to social problems, such as the patient not being able to live alone, and
JUNE 1994 23:6 ANNALS OF EMERGENCYMEDICINE
the need for training in some of the elderly patients before discharge. The Table shows each criterion that was cause for admission. Two hundred fifty (58%) of the hospitalized patients fulfilled multiple guideline criteria. Thirty patients (7.0%) were hospitalized even though none of the guideline criteria were met. Twenty-eight of these patients had one or more of the following symptoms: severe headache, vomiting, amnesia for less than 15 minutes, or unconsciousness for less than 15 minutes. In two cases, no information was provided on these items. DISCUSSION
The use of imaging after minor head injury was the subject of major controversy throughout the 1980s. In 1980, Masters s concluded that skull films alone seldom indicate more serious internal head injury, and he found no skull films to be effective contributors to evaluation, management, or prognosis of outcome after head trauma. Nevertheless, the discussion continued, and numerous studies on the value of skull radiographs in the evaluation of minor head injuries have been performed since. 9-15 Differences of opinion exist between radiologists, who say that skull radiographs are expensive and have a very low yield,11,13 and neurosurgeons, who recommend skull radiographs for all patients who sustain a head injury, minor or major. 1,2 Other neurosurgeons 1~ have concluded that skull radiographs should not be used to determine the need for hospital admission. In 1987, an American muhidisciplinary panel recommended an approach based on the distnbution of the patients in low-risk, moderate-risk, and high-risk groups. Only in the moderate-risk group was skull radiograph Table.
Number of patients in whom each criterion was the exclusive cause for admission Criterion
Confusion or aggression Impaired consciousness Neurologic signs Suspected skull fracture Alcohol intoxication Convulsions Amnesia for more than 15 minutes Unconsciousfor more than 15 minutes Age less than 3 years No responsible person in the home
No of Patients (%)
11 (2.6) 43 (10.g) 15 (3.5) 8 (1.9) 21 (4.9) 6 (1.4) 16 (3.7) 1 (0.2) 11 (2.6) 18 (4.2)
1281
NEUROIMAGING Duus et al
indicated, and then only rarely. 9 Feuerman et al > found no benefit from the use of skull radiographs and concluded that the neurologic examination, including the Glasgow Coma Scale score and evaluation Of mental status, was the best predictor of intracranial complications after minor head injuries. Correspondingly, de Lacey et a1.3 emphasized that loose and liberal policies on skull radiographs be abandoned. Recently, a retrospective Scandinavian study of 1,876 patients found no justification for skull radiographs after minor head injuries. 15 There is no doubt that a considerable portion of the skull radiographs in the ED are obtained for medicolegal reasons. 12 Authors have stressed that it is the ED physician who runs the risk of a charge of negligence if a patient is discharged without a skull radiograph and later develops an intracranial complication. 16 Thus, it is essential to reliably predict the outcome after minor head injuries. The increased use of technology and the risk of malpractice lawsuits have resulted in the use of more refined diagnostic tests, even in patients with trivial minor head injuries. Recently, American traumatologists have recommended the use of CT scanning to determine which patients to discharge from the ED after a minor head injury. 4-<1r Magnetic resonance imaging after minor head injury has identified anatomic lesions in 10% of these patients discharged from the ED. The clinical consequence of these findings has been questioned) 8 The medical malpractice lawsuit is a very rare phenomenon in Scandinavia. This led to our being able to base this study on the clinical admission guidelines generated in a retrospective study, t ~ as well as o~er studies.l,8,2~ In developing our guidelines, we stressed the importance of the findings in the ED (Figure, first five items). The symptoms from the history (Figure, fifth through eighth items) were an indication for hospitalization only if they were very pronounced, ie, amnesia and witnessed unconsciousness for more than 15 minutes. This is emphasized by the finding that only 16 patient s and one patient, respectively, were admitted with one of these criteria as the exclusive cause. EDs are staffed by junior physicians with limited clinical experience. [t is well known that skull radiographs are difficult to evaluate. Thitlainayagam et a122 found a positivepredictive value of skull fracture found by ED physicians of only 0.59; the negative-predictive value was 0.99. Furthermore, skull radiographs done in the ED are very often of unsatisfactory quality, especially in uncooperative patients. 15 If the guidelines for skull radiograph published by a group of neurosurgeons t had been adopted for use in our
1 2 82
study, at least 689 skull radiographs should have been taken in the ED during the study period. Extrapolating these figures to the entire nation of Denmark, at least 21,000 skull radiographs after minor head injury would be obtained each year. We explicitly abandoned the use of skull radiographs in our study. Instead, we used clinicat guidelines as determinants of admission. No patient was discharged and had subsequent hospitalization because of intracranial complications related to minor head injury. In retrospect, only four patients needed treatment. Thus, one Can question whether it was necessary to admit the remaining 426 patients. However, we do not believe that the clinical situation in the ED would permit us to send more Patients home than we did in this study. To further elucidate the problems concerning the primary treatment of patients with minor head injuries, we will continue the data collection. CONCLUSION
The use of guidelines based primarily on the clinical findings in the ED allows the safe primary evaluation of patients with minor head injuries. The ED physician does not need skull radiographs or other neuroimaging methods to decide which patients to admit. REFERENCES 1. Guidelines for initial management after head injury in adults. Suggestions from a group of neurosurgeons. Br Mad J 1984;288:983-985. 2. Jennett B: Skull x-rays after mild head injuries. Arch EmergMed1987i4:133-135. 3. Klauber MR, Maishall LF, Luerssen T, et al: Determinants of head injury mortality: Importance of the low risk patient. Neurosurgery1989;24:31-36. 4. Stein SC, Ross SE: The value of computed tomographic scans in patients with low-risk head injuries. Neurosurgery1990;26:638-640. 5. Stein SCI O'Malley KF, Ross SEI Is routine computed tomography scanning too expensive for mild head injury? Ann EmergMad1991;20:1286-1289 6. Livingston DH, Loder PA, Koziol J, et al! The use of CT scanning to triage patients requiring admission following minimal head injury. J Trauma1991;31:483-487. 7. Pitts LH: The role ofneuroimaging in minor head injury. Ann EmergMed1991;2G:1387-1388 8. Masters SJ: Evaluation of head trauma: Efficacy of skull films. AJR1980;135:539-547. 9. Masters SJ, McClean PM, Arcarese JS, et al: Skull x-ray examinations after head trauma. Recommendations by a multidisciplinary panel and.validatio~ study. NEngtJMed1987;316:8491. 10. Cooper PR, He V: Role of emergency skull x-ray films in the evaluation of the head injured patient: A retrospective study. Neurosurgery1983;13:136-140. 11. Costs and benefits of skull radiography for head injury. A national study by the Royal College of Radiologists. Lancet1981 ;2:791-795. 12. Balasubramaniam S, Kapadia T, Campbell JA, et al: Efficacy of skull radiography. Am J Surg 1981 ;142:366-369: 13. de Lacey G, McCabe M, Constant O, et al: Testing a policy for skull radiography (and admission) following mild head injury. BrJRadie11990;63:14-18
ANNALS OF EMERGENCY MEDICINE 23:6
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Address for reprints: BR Duus, MD Willemoesgade 39, 3.tv. Copenhagen 0, Denmark Fax +045 35 36 67 33
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