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Prehospital use of the glasgow coma scale in severe head injury
The Journal of Emergency Medicine, Vol. 2, pp. 1-6.1984
Printed in the USA • Copyright (c} 1984 Pergamon Press Ltd m m ~ A R m ~ m ' J I ~
| ~
PREHOSPITAL USE OF THE GLASGOW COMA SCALE IN SEVERE HEAD INJURY J a m e s V. Winkler, MD,* Peter Rosen,
MD,I" and
Edward J. Alfry,
MD:I:
*AssociateStaff, EmergencyMedicalServices,DenverGeneral Hospital,StaffPhysician,EmergencyMedicine, Porter Memorial Hospital, Denver, Colorado; tDirector, Emergency Medical Services, Denver General Hospital, Denver, Colorado; and SUniversityof Arizona, HealthSciencesCenter, Collegeof Medicine, Departmentof Surgery, Tucson, Arizona Reprint address: James V. Winkler, MD, 880 College Avenue, Boulder, CO 80302
[] Abstract--To determine the prognostic value of prehospital Glasgow Coma Scale (GCS) scores in severe blunt head injuries, the GCS at the scene of injury (INGCS) and the GCS in the emergency department (EDGCS) were compared with neurologic outcomes in 33 consecutive head-injured patients. Patients were categorized according to final outcome: Group I ( n = 7 ) had no neuroiogic deficits, group II (n = 3) had only minor neurologic deficits, group III (n = 11) had major neurologic deficits, and group IV (n = 12) died. Mean INGCS was not significantly different for any of the four groups (range 4.14 to 4.67). However, mean EDGCS was s i g n i f i c a n t l y higher ( P < . 0 5 ) for group I (9.43+4.08) than for group IV (5.17+3.13), and mean EDGCS for groups I and II (8.8 43.99) were significantly higher ( P < . 0 5 ) than that of groups III and IV (5.7-4-.2.88). The net change in GCS ( E D G C S - INGCS) was significantly higher ( P < .05) for groups I and 11 (4.5 + 4.4) than for groups III and IV (1.3 + 2.91). We conclude that INGCS alone has no prognostic value, but that EDGCS and any prehospital change in GCS may have prognostic value for severely head-injured patients.
[] K e y w o r d s - h e a d injuries; Glasgow Coma Scale; coma; trauma; prehospital
Introduction Since the first d e s c r i p t i o n o f the G l a s g o w C o m a Scale (GCS) in 1974 by Teasdale and Jennett,' many emergency departments and neurosurgical intensive care units have used the scale to m e a s u r e d e p t h o f c o m a in severely h e a d - i n j u r e d patients. The G C S score (Table 1) has p r o v e d to be a reliable measurement of neurologic impairment a n d a highly a c c u r a t e i n d i c a t o r o f o u t c o m e . 2-s H o w e v e r , t h e r e have been few p u b l i s h e d r e p o r t s assessing the p r o g n o s t i c value o f G C S scores in the p r e h o s p i t a l setting or very early in the clinical course o f head injury. Several p r e v i o u s r e p o r t s have suggested t h a t the G C S scores can accura t e l y p r e d i c t o u t c o m e o n l y in p a t i e n t s whose c o m a lasts longer t h a n six h o u r s 6-8 a n d when the G C S score is r e p o r t e d 24 hours a f t e r the injury. 9 Because those criteria are not applicable to emergency medicine, this s t u d y was u n d e r t a k e n to assess the p r o g n o s t i c value, if any, o f p r e h o s p i t a l a n d e m e r g e n c y d e p a r t m e n t G C S scores in severe b l u n t h e a d i n j u r y with r e l a t i v e l y short p a r a m e d i c response times to the scene o f injury.
Original Contributions presents papers of interest to both academic and practicing physicians. This section of J E M is coordinated by John A . Marx, MD, of Denver General Hospital. RECEIVED: 22 D e c e m b e r 1983; ACCEPTED: 28 J u n e 1984
0736-4679/84 $3.00 + .00
James V. Winkler, Peter Rosen, and Edward J. Alfry
Table 1. Glasgow Coma Scale Eye opening
Spontaneous To verbal command To pain No response
4 3 2 1
Best verbal response
Oriented Confused Inappropriate Incomprehensible No response
5 4 3 2 1
Best motor
Obeys verbal commands Localizes pain Withdraws to painful stimulus Flexion to pain (decorticate) Extension to pain (decerebrate) No response
6 5
response
Total score (range)
Materials
4 3 2 1 3-15
and Methods
A prospective study of all severe blunt head injuries admitted to two urban neurosurgical trauma centers in the Denver metropolitan area was conducted over a 4-month period. Thirty-three consecutive patients were admitted to the final study. Each o f those patients met the following criteria: an initial GCS score of 7 or less at the scene of injury, evidence of trauma compatible with a severe blunt head injury, systolic blood pressure of at least 60 mm Hg and no cardiopulmonary resuscitation (CPR) required at the scene of injury, direct admission from the emergency department to the neurosurgical intensive care unit or the operating room, and a hospital course, management, and final diagnosis consistent with severe head injury. All patients received comparable, but not identical, treatment, which frequently included tracheal intubation, osmotic and loop diuretics, steroids, intracranial pressure monitors, and surgery when needed. Several patients had injuries other than head injuries alone, but the decreased level of consciousness was determined to be primarily due to direct head trauma for the patient to be included in the study. Patients with gunshot wounds to the head or re-
quiring CPR for other injuries were excluded. Patients who awakened quickly had no further evidence of head injury, and evaluation of the record showed that alcohol or drugs alone may have been responsible for the initial low GCS score were also excluded. Paramedic "response time" was recorded electronically with a central dispatch from the time the call was received to the time the paramedic unit arrived on the scene of injury. "Return time" was the total prehospital time from the time the paramedics arrived at the scene of injury to the time of arrival in the emergency department. Patients who required interhospital transfer were not included in the study. GCS scores were determined by the paramedics at the scene o f injury and by the physician in the emergency department. Each attending paramedic and emergency physician was then interviewed by one of the authors (J.W.). Specific questions regarding the patient's eye, verbal, and motor responses were asked during the interview to verify the accuracy o f the GCS scores. All patients in this study were admitted to the neurosurgical intensive care unit and treated by the neurosurgical service. Each patient was followed during hospitalization to determine the neurologic impairment. Patients were categorized 8 to 12 weeks after injury according to a modification of the Glasgow Outcome Scale 1°''1 (Table 2) as follows: Group I had no neurologic deficits, a full recovery, and could return to an independent lifestyle; group II had only minor neurologic deficits (mild hemiparesis or memory loss) and could return home and generally function independently after rehabilitation; group III had major neurologic deficits resulting in either severe persistent disability or in a vegetative state and required institutionalized care or were dependent on continual nursing care at home; and group IV died. Groups I and II were combined to provide a "favorable" outcome group and groups III and IV were combined to provide an "unfavorable" outcome group.
9
Prehospital Glasgow Coma Scale
Table 2. Definition of Neurologic Outcome Groups Neurologic Outcome
Group
Neurologic Deficits
"Favorable"
I II
No deficits Minor disability (mild dysphasia, ataxia, hemiparesis, or memory loss)
"Unfavorable"
III
Severe disability (needs supportive care, institutionalized) Died
IV
INGCS was compared with EDGCS for each of the outcome groups, and the net change in GCS scores from the scene of injury to arrival in the emergency department was also compared with each outcome group. Results were analyzed using Student's t test.
Results
The paramedics responded quickly to all of the patients in this series with a mean response time of 5.18 minutes (SD4-3.14). The mean return time was 21.1 minutes (4- 9.28) minutes. Seven patients (21.2%) eventually recovered with no neurologic deficits (group I), 3 patients (9.1%) had only minor neurologic deficits (group II), 11 patients (33.3%) had major neurologic deficits ( g r o u p III), and 12 patients (36.4%) died (group IV) (Table 3). There was no significant difference in response time or return time for any of the outcome groups. Mean I N G C S for group I was 4.14 (4- 1.68), for group II, 4.67 (4- 1.53); for group III, 4.45 (4- 1.51); and for group IV, 4.33 (4- 1.72) (Table 3). There was no significant difference in mean INGCS for any of the individual outcome groups. The mean EDGCS for group I was 9.43 (4-4.08); for group II, 7.33 (4-4.16); for group III, 6.27 (4-2.61); and for group IV, 5.17 (-4-3.13) (Table 3). Mean E D G C S for group I was significantly higher than that
3
of group IV ( P < .05), but there was no significant difference EDGCS with any other groups. Mean INGCS for patients who had a favorable outcome (groups I and II) was 4.30 (4- 1.57) and was 4.39 (4- 1.59) for patients with an unfavorable outcome (groups III and IV) (Table 4). There was no significant difference in these groups. However, mean EDGCS for patients with a favorable o u t c o m e was 8.80 (4-3.99) and 5.70 (4- 2.80) for patients with an unfavorable outcome; this was a significant difference ( P < . 0 5 ) (Table 4) (Figure 1). Net change in GCS scores from the scene of injury to the emergency department ( E D G C S - I N G C S ) was 5.29 (+4.75) for group I, 2.67 (4-3.51) for Group II, 1.82 (4-3.28) for g r o u p III, and 0.83 (4-2.59) for Group IV. The net change in GCS scores for group I was significantly higher than that in group IV ( P < .05), but there was no significant difference in the other groups (Table 3). The net change in GCS scores for patients with a favorable outcome was 4.50 (±4.40), and this was significantly different ( P < .05) from the unfavorable outcome group whose net change in GCS score was 1.30 (4-2.91) (Table 4). In this series 18 patients had a low net change (2 or less) in GCS score during the prehospital return time. Fifteen of those patients (83.3%) had an unfavorable outcome, and eight patients (44.4%) died (Table 5).
Discussion
Previous studies have indicated that GCS scores alone have prognostic value for severely head-injured patients. 2,4-6 Because this coma scale is frequently used in neurosurgical intensive care units and emergency departments, many prehospital care systems also employ the scale when assessing head trauma victims at the scene of injury. 12 The results of this study show that initial GCS scores at the scene of injury appear to have no prognostic value for pa-
James V. Winkler, Peter Rosen, and Edward J. Alfry
Table 3. GCS Scores for Each Neurologic Outcome Group GCS at the Scene
Group I II III IV
4.14 ( ± 4.67 (± 4.45 (± 4.33 (±
1.68) 1.53) 1.51) 1.72)
GCS at the Emergency Department
Net Change in GCS
Percentage of Patients
9.43 ( ± 4.08)* 7.33 (±4.16) 6.27 (±2.61) 5.17 (±3.13)
5.29 ( ± 4.75)* 2.67 (±3.51) 1.82 (±3.28) 0.83 (±2.59)
21.1 9.1 33.3 36.4
*P<.05 when comparedwith group IV. Standarddeviationin parentheses.
Table 4. GCS Scores in Patients with Favorable end Unfavorable Outcomes
Outcome Favorable Unfavorable
GCS at the Scene
GCS at the Emergency Department
Net Change in GCS
Percentage of Patients
4.30 (± 1.57) 4.39 ( ± 1.59)
8.80 (±3.99)* 5.70 ( ± 2.80)
4.50 (±4.40)* 1.30 ( ± 2.91 )
30.3 69.7
*P< .05 when comparedwith the unfavorablegroup. 15
mm
10
a
Glasgow Coma Scale * 8.80
5.70 4.$0 5
-,,
3
--
"4 . $ 9
B Mean G C S at the S c e n e
Mean in t h e
GCS E.D.
I
m
Favorable Outcome
Unfavorable Outcome
* = p
Figure 1. Mean Glasgow Coma Scale (GCS) scores for "unfavorable" end "favorable" outcome groups following severe head injury. The two columns on the left represent the mean GCS scores at the scene of injury. A significantly hlgher mean GCS score (P < .05) for the "favorable" outcome group at the time of arrival in the emergency department is seen in the columns at the right.
Prehospital Glasgow Coma Scale Table 5. Patients with Low (2 or Less) Prehospital Change in GCS Score
Group
No. of Patients with Prehospital GCS Score Changeof 2 or Less
I
2
II III IV
1 7 8
Percentage 11.1 5.6 38.9 44.4
tients who suffered severe blunt head injuries. With a response time averaging approximately five minutes, the paramedics appeared to arrive on the scene so early in the clinical course of the head injury that the initial GCS score had no prognostic meaning. Strict patient selection criteria allowed a homogeneous population to be used for this prospective study. Only patients who were in a c o m a at the scene of injury and whose coma was due primarily to severe blunt head injury were admitted to the study. Patients who had a GCS score of 8 or greater at the scene, whose coma was due to ethanol or other drugs, who had a systolic blood pressure less than 60 m m Hg or required CPR at the scene of injury (and therefore possibly dead at the scene), who sustained a gunshot wound to the head, or whose head injury was later felt to be minor or moderate were not included. Approximately 70% of the patients in this study had an unfavorable outcome (severely disabled, persistent vegetative state, or died) (Table 4) and that is comparable to other series with similar patient selection criteria.4.9.,3 Included in this study were several patients who died of their head injuries less than six hours after the accident. Postmortum review showed that each of these patients had conclusive evidence of a fatal head injury. Several definitions of "severe" head injury have stated that a GCS score of 7 (or 8) or less must be present for at least six hours. 68 Jennett and Teasdale have reported that GCS assessment prior to six hours' duration of coma m a y weaken
the prognostic value of the scale. 6.14 However, other studies have noted that duration of coma for six hours ls-'7 and a GCS score of 8 or less 's may not be necessary to define "severe" head injury. Previous reports have suggested that GCS scores recorded in the emergency department can predict outcome from head injuriesJ 339 and the results of this study appear to support those observations. GCS scores recorded in the emergency department were significantly higher for those patients who had a full neurologic recovery than for those who died. Those scores were also significantly higher for patients with a favorable outcome than for patients with an unfavorable outcome (Figure 1). However, patients with minor and major neurologic outcomes could not be predicted by the emergency department GCS score alone in this study. F u r t h e r investigation is needed to elucidate the prognostic value of the e m e r g e n c y d e p a r t m e n t GCS score alone. This study demonstrates that a prehospital change in the GCS score was signific a n t l y h i g h e r f o r p a t i e n t s w h o fully recovered t h a n for patients who died. There was also a significant net change in prehospital GCS scores for patients with a favorable outcome compared with patients who had an unfavorable outcome (Table 4). In this series, 83% of patients who had a prehospital GCS score change of 2 or less had an u n f a v o r a b l e o u t c o m e (total o f groups III and IV in Table 5), and this represented minimal or no improvement in the GCS score during the prehospital time. Other authors have recommended adding pupillary response to light and oculocephalic reflex response to the GCS and early neurologic assessment of coma due to head injury. 2° However, pupillary response to light is often obscured by local trauma, previous surgery, or medications. Oculocephalic reflexes require movement of the head, which is almost always tightly secured until cervical spine injury has been excluded. The GCS score alone appears to be the best available method for neu-
6
James V. Winkler, Peter Rosen, and Edward J. Alfry
rologic assessment of depth of coma in the prehospital setting. This preliminary study suggests that the GCS score at the scene of injury has no prognostic value. However, recording GCS scores initially and again in the emergency department will provide a prehospital net change in the GCS score that could prove
useful for predicting outcome from severe head injury. An increase of the GCS score in the prehospital setting is frequently associated with a better prognosis, and those patients who continue to have a low GCS score with an increase of 2 or less by the time they arrive in the emergency department appear to have a substantially worse prognosis.
REFERENCES 1. Teasdale G, Jennett B: Assessment of coma and impaired consciousness. A practical scale. Lancet 1974; 2:81-84. 2. Jane JA, Rimel RW: Prognosis in head injury. Clin Neurosurg 1982; 29:346-352. 3. Seelig JM, Becker DP, Miller JD, et al: Traumatic acute subdural hematoma. Major mortality reduction in comatose patients treated within four hours. NEngl JMed 1981; 304:1511-1518. 4. Langfitt TW: Measuring the outcome from head injuries. J Neurosurg 1978; 48:673-678. 5. Bruce DA, Gennarelli TA, Langfitt TW: Resuscitation from coma due to head injury. Crit Care Med 1978; 6:254-269. 6. Jennett B, Teasdale G: Aspects of coma after head injury. Lancet 1977; 1:878-881. 7. Jennett B, Teasdale G, Fry J, et al: Treatment for severe head injury. J Neurosurg Psychol 1980; 43:289-295. 8. Gennarelli TA, Spielman GM, Langfitt TW, et al: Influence of the type of intracranial lesion on outcome from severe head injury. A multicenter study using a new classification system. J Neurosurg 1982; 56:26-32. 9. Young B, Rapp RP, Norton JH, et al: Early prediction of outcome in head-injured patients. J Neurosurg 1981; 54:300-303. 10. Jennett B, Bond M: Assessment of outcome after severe brain damage. A practical scale. Lancet 1975; 1:480-484. 11. Becker DP, Miller JD, Ward JD, et al: The outcome from severe head injury with early diagnosis
and intensive management. J Neurosurg 1977; 47:491-502. 12. Rimel RW, Jane JA, Edlich RF: An injury severity scale for comprehensive management of central nervous system trauma. JACEP 1979; 8:64-67. 13. Clifton GL, Grossman RG, Makela ME, et al: Neurological course and correlated computerized tomography findings after severe closed head injury. J Neurosurg 1980; 52:611-624. 14. Jennett B, Teasdale G, Braakman R, et al: Predicting outcome in individual patients after severe head injury. Lancet 1976; 1:1031-1034. 15. Rimel RW, Giordani B, Barth JT, et al: Disability caused by minor head injury. Neurosurgery 1981; 9:221-228. 16. Rimel RW, Giordani B, Barth JT, et al: Moderate head injury: Completing the spectrum of brain injury. Neurosurgery 1982; 11:344-351. 17. Braakman R, Gelpke G J, Habbema JD, et al: Systematic selection of prognostic features in patients with severe head injury. Neurosurgery 1980; 6:362-370. 18. Langfitt TW, Genarelli TA: Can outcome from head injury be improved? J Neurosurg 1982; 56:19-25. 19. Miller D J, Butterworth JF, Gudeman SK, et al: Further experience in the management of severe head injury. J Neurosurg 1981; 54:289-299. 20. Levati A, Farina ML, Vecchi G, et al: Prognosis of severe head injuries. JNeurosurg 1982; 57:779783.
Printed in the USA • Copyright (c} 1984 Pergamon Press Ltd m m ~ A R m ~ m ' J I ~
| ~
PREHOSPITAL USE OF THE GLASGOW COMA SCALE IN SEVERE HEAD INJURY J a m e s V. Winkler, MD,* Peter Rosen,
MD,I" and
Edward J. Alfry,
MD:I:
*AssociateStaff, EmergencyMedicalServices,DenverGeneral Hospital,StaffPhysician,EmergencyMedicine, Porter Memorial Hospital, Denver, Colorado; tDirector, Emergency Medical Services, Denver General Hospital, Denver, Colorado; and SUniversityof Arizona, HealthSciencesCenter, Collegeof Medicine, Departmentof Surgery, Tucson, Arizona Reprint address: James V. Winkler, MD, 880 College Avenue, Boulder, CO 80302
[] Abstract--To determine the prognostic value of prehospital Glasgow Coma Scale (GCS) scores in severe blunt head injuries, the GCS at the scene of injury (INGCS) and the GCS in the emergency department (EDGCS) were compared with neurologic outcomes in 33 consecutive head-injured patients. Patients were categorized according to final outcome: Group I ( n = 7 ) had no neuroiogic deficits, group II (n = 3) had only minor neurologic deficits, group III (n = 11) had major neurologic deficits, and group IV (n = 12) died. Mean INGCS was not significantly different for any of the four groups (range 4.14 to 4.67). However, mean EDGCS was s i g n i f i c a n t l y higher ( P < . 0 5 ) for group I (9.43+4.08) than for group IV (5.17+3.13), and mean EDGCS for groups I and II (8.8 43.99) were significantly higher ( P < . 0 5 ) than that of groups III and IV (5.7-4-.2.88). The net change in GCS ( E D G C S - INGCS) was significantly higher ( P < .05) for groups I and 11 (4.5 + 4.4) than for groups III and IV (1.3 + 2.91). We conclude that INGCS alone has no prognostic value, but that EDGCS and any prehospital change in GCS may have prognostic value for severely head-injured patients.
[] K e y w o r d s - h e a d injuries; Glasgow Coma Scale; coma; trauma; prehospital
Introduction Since the first d e s c r i p t i o n o f the G l a s g o w C o m a Scale (GCS) in 1974 by Teasdale and Jennett,' many emergency departments and neurosurgical intensive care units have used the scale to m e a s u r e d e p t h o f c o m a in severely h e a d - i n j u r e d patients. The G C S score (Table 1) has p r o v e d to be a reliable measurement of neurologic impairment a n d a highly a c c u r a t e i n d i c a t o r o f o u t c o m e . 2-s H o w e v e r , t h e r e have been few p u b l i s h e d r e p o r t s assessing the p r o g n o s t i c value o f G C S scores in the p r e h o s p i t a l setting or very early in the clinical course o f head injury. Several p r e v i o u s r e p o r t s have suggested t h a t the G C S scores can accura t e l y p r e d i c t o u t c o m e o n l y in p a t i e n t s whose c o m a lasts longer t h a n six h o u r s 6-8 a n d when the G C S score is r e p o r t e d 24 hours a f t e r the injury. 9 Because those criteria are not applicable to emergency medicine, this s t u d y was u n d e r t a k e n to assess the p r o g n o s t i c value, if any, o f p r e h o s p i t a l a n d e m e r g e n c y d e p a r t m e n t G C S scores in severe b l u n t h e a d i n j u r y with r e l a t i v e l y short p a r a m e d i c response times to the scene o f injury.
Original Contributions presents papers of interest to both academic and practicing physicians. This section of J E M is coordinated by John A . Marx, MD, of Denver General Hospital. RECEIVED: 22 D e c e m b e r 1983; ACCEPTED: 28 J u n e 1984
0736-4679/84 $3.00 + .00
James V. Winkler, Peter Rosen, and Edward J. Alfry
Table 1. Glasgow Coma Scale Eye opening
Spontaneous To verbal command To pain No response
4 3 2 1
Best verbal response
Oriented Confused Inappropriate Incomprehensible No response
5 4 3 2 1
Best motor
Obeys verbal commands Localizes pain Withdraws to painful stimulus Flexion to pain (decorticate) Extension to pain (decerebrate) No response
6 5
response
Total score (range)
Materials
4 3 2 1 3-15
and Methods
A prospective study of all severe blunt head injuries admitted to two urban neurosurgical trauma centers in the Denver metropolitan area was conducted over a 4-month period. Thirty-three consecutive patients were admitted to the final study. Each o f those patients met the following criteria: an initial GCS score of 7 or less at the scene of injury, evidence of trauma compatible with a severe blunt head injury, systolic blood pressure of at least 60 mm Hg and no cardiopulmonary resuscitation (CPR) required at the scene of injury, direct admission from the emergency department to the neurosurgical intensive care unit or the operating room, and a hospital course, management, and final diagnosis consistent with severe head injury. All patients received comparable, but not identical, treatment, which frequently included tracheal intubation, osmotic and loop diuretics, steroids, intracranial pressure monitors, and surgery when needed. Several patients had injuries other than head injuries alone, but the decreased level of consciousness was determined to be primarily due to direct head trauma for the patient to be included in the study. Patients with gunshot wounds to the head or re-
quiring CPR for other injuries were excluded. Patients who awakened quickly had no further evidence of head injury, and evaluation of the record showed that alcohol or drugs alone may have been responsible for the initial low GCS score were also excluded. Paramedic "response time" was recorded electronically with a central dispatch from the time the call was received to the time the paramedic unit arrived on the scene of injury. "Return time" was the total prehospital time from the time the paramedics arrived at the scene of injury to the time of arrival in the emergency department. Patients who required interhospital transfer were not included in the study. GCS scores were determined by the paramedics at the scene o f injury and by the physician in the emergency department. Each attending paramedic and emergency physician was then interviewed by one of the authors (J.W.). Specific questions regarding the patient's eye, verbal, and motor responses were asked during the interview to verify the accuracy o f the GCS scores. All patients in this study were admitted to the neurosurgical intensive care unit and treated by the neurosurgical service. Each patient was followed during hospitalization to determine the neurologic impairment. Patients were categorized 8 to 12 weeks after injury according to a modification of the Glasgow Outcome Scale 1°''1 (Table 2) as follows: Group I had no neurologic deficits, a full recovery, and could return to an independent lifestyle; group II had only minor neurologic deficits (mild hemiparesis or memory loss) and could return home and generally function independently after rehabilitation; group III had major neurologic deficits resulting in either severe persistent disability or in a vegetative state and required institutionalized care or were dependent on continual nursing care at home; and group IV died. Groups I and II were combined to provide a "favorable" outcome group and groups III and IV were combined to provide an "unfavorable" outcome group.
9
Prehospital Glasgow Coma Scale
Table 2. Definition of Neurologic Outcome Groups Neurologic Outcome
Group
Neurologic Deficits
"Favorable"
I II
No deficits Minor disability (mild dysphasia, ataxia, hemiparesis, or memory loss)
"Unfavorable"
III
Severe disability (needs supportive care, institutionalized) Died
IV
INGCS was compared with EDGCS for each of the outcome groups, and the net change in GCS scores from the scene of injury to arrival in the emergency department was also compared with each outcome group. Results were analyzed using Student's t test.
Results
The paramedics responded quickly to all of the patients in this series with a mean response time of 5.18 minutes (SD4-3.14). The mean return time was 21.1 minutes (4- 9.28) minutes. Seven patients (21.2%) eventually recovered with no neurologic deficits (group I), 3 patients (9.1%) had only minor neurologic deficits (group II), 11 patients (33.3%) had major neurologic deficits ( g r o u p III), and 12 patients (36.4%) died (group IV) (Table 3). There was no significant difference in response time or return time for any of the outcome groups. Mean I N G C S for group I was 4.14 (4- 1.68), for group II, 4.67 (4- 1.53); for group III, 4.45 (4- 1.51); and for group IV, 4.33 (4- 1.72) (Table 3). There was no significant difference in mean INGCS for any of the individual outcome groups. The mean EDGCS for group I was 9.43 (4-4.08); for group II, 7.33 (4-4.16); for group III, 6.27 (4-2.61); and for group IV, 5.17 (-4-3.13) (Table 3). Mean E D G C S for group I was significantly higher than that
3
of group IV ( P < .05), but there was no significant difference EDGCS with any other groups. Mean INGCS for patients who had a favorable outcome (groups I and II) was 4.30 (4- 1.57) and was 4.39 (4- 1.59) for patients with an unfavorable outcome (groups III and IV) (Table 4). There was no significant difference in these groups. However, mean EDGCS for patients with a favorable o u t c o m e was 8.80 (4-3.99) and 5.70 (4- 2.80) for patients with an unfavorable outcome; this was a significant difference ( P < . 0 5 ) (Table 4) (Figure 1). Net change in GCS scores from the scene of injury to the emergency department ( E D G C S - I N G C S ) was 5.29 (+4.75) for group I, 2.67 (4-3.51) for Group II, 1.82 (4-3.28) for g r o u p III, and 0.83 (4-2.59) for Group IV. The net change in GCS scores for group I was significantly higher than that in group IV ( P < .05), but there was no significant difference in the other groups (Table 3). The net change in GCS scores for patients with a favorable outcome was 4.50 (±4.40), and this was significantly different ( P < .05) from the unfavorable outcome group whose net change in GCS score was 1.30 (4-2.91) (Table 4). In this series 18 patients had a low net change (2 or less) in GCS score during the prehospital return time. Fifteen of those patients (83.3%) had an unfavorable outcome, and eight patients (44.4%) died (Table 5).
Discussion
Previous studies have indicated that GCS scores alone have prognostic value for severely head-injured patients. 2,4-6 Because this coma scale is frequently used in neurosurgical intensive care units and emergency departments, many prehospital care systems also employ the scale when assessing head trauma victims at the scene of injury. 12 The results of this study show that initial GCS scores at the scene of injury appear to have no prognostic value for pa-
James V. Winkler, Peter Rosen, and Edward J. Alfry
Table 3. GCS Scores for Each Neurologic Outcome Group GCS at the Scene
Group I II III IV
4.14 ( ± 4.67 (± 4.45 (± 4.33 (±
1.68) 1.53) 1.51) 1.72)
GCS at the Emergency Department
Net Change in GCS
Percentage of Patients
9.43 ( ± 4.08)* 7.33 (±4.16) 6.27 (±2.61) 5.17 (±3.13)
5.29 ( ± 4.75)* 2.67 (±3.51) 1.82 (±3.28) 0.83 (±2.59)
21.1 9.1 33.3 36.4
*P<.05 when comparedwith group IV. Standarddeviationin parentheses.
Table 4. GCS Scores in Patients with Favorable end Unfavorable Outcomes
Outcome Favorable Unfavorable
GCS at the Scene
GCS at the Emergency Department
Net Change in GCS
Percentage of Patients
4.30 (± 1.57) 4.39 ( ± 1.59)
8.80 (±3.99)* 5.70 ( ± 2.80)
4.50 (±4.40)* 1.30 ( ± 2.91 )
30.3 69.7
*P< .05 when comparedwith the unfavorablegroup. 15
mm
10
a
Glasgow Coma Scale * 8.80
5.70 4.$0 5
-,,
3
--
"4 . $ 9
B Mean G C S at the S c e n e
Mean in t h e
GCS E.D.
I
m
Favorable Outcome
Unfavorable Outcome
* = p
Figure 1. Mean Glasgow Coma Scale (GCS) scores for "unfavorable" end "favorable" outcome groups following severe head injury. The two columns on the left represent the mean GCS scores at the scene of injury. A significantly hlgher mean GCS score (P < .05) for the "favorable" outcome group at the time of arrival in the emergency department is seen in the columns at the right.
Prehospital Glasgow Coma Scale Table 5. Patients with Low (2 or Less) Prehospital Change in GCS Score
Group
No. of Patients with Prehospital GCS Score Changeof 2 or Less
I
2
II III IV
1 7 8
Percentage 11.1 5.6 38.9 44.4
tients who suffered severe blunt head injuries. With a response time averaging approximately five minutes, the paramedics appeared to arrive on the scene so early in the clinical course of the head injury that the initial GCS score had no prognostic meaning. Strict patient selection criteria allowed a homogeneous population to be used for this prospective study. Only patients who were in a c o m a at the scene of injury and whose coma was due primarily to severe blunt head injury were admitted to the study. Patients who had a GCS score of 8 or greater at the scene, whose coma was due to ethanol or other drugs, who had a systolic blood pressure less than 60 m m Hg or required CPR at the scene of injury (and therefore possibly dead at the scene), who sustained a gunshot wound to the head, or whose head injury was later felt to be minor or moderate were not included. Approximately 70% of the patients in this study had an unfavorable outcome (severely disabled, persistent vegetative state, or died) (Table 4) and that is comparable to other series with similar patient selection criteria.4.9.,3 Included in this study were several patients who died of their head injuries less than six hours after the accident. Postmortum review showed that each of these patients had conclusive evidence of a fatal head injury. Several definitions of "severe" head injury have stated that a GCS score of 7 (or 8) or less must be present for at least six hours. 68 Jennett and Teasdale have reported that GCS assessment prior to six hours' duration of coma m a y weaken
the prognostic value of the scale. 6.14 However, other studies have noted that duration of coma for six hours ls-'7 and a GCS score of 8 or less 's may not be necessary to define "severe" head injury. Previous reports have suggested that GCS scores recorded in the emergency department can predict outcome from head injuriesJ 339 and the results of this study appear to support those observations. GCS scores recorded in the emergency department were significantly higher for those patients who had a full neurologic recovery than for those who died. Those scores were also significantly higher for patients with a favorable outcome than for patients with an unfavorable outcome (Figure 1). However, patients with minor and major neurologic outcomes could not be predicted by the emergency department GCS score alone in this study. F u r t h e r investigation is needed to elucidate the prognostic value of the e m e r g e n c y d e p a r t m e n t GCS score alone. This study demonstrates that a prehospital change in the GCS score was signific a n t l y h i g h e r f o r p a t i e n t s w h o fully recovered t h a n for patients who died. There was also a significant net change in prehospital GCS scores for patients with a favorable outcome compared with patients who had an unfavorable outcome (Table 4). In this series, 83% of patients who had a prehospital GCS score change of 2 or less had an u n f a v o r a b l e o u t c o m e (total o f groups III and IV in Table 5), and this represented minimal or no improvement in the GCS score during the prehospital time. Other authors have recommended adding pupillary response to light and oculocephalic reflex response to the GCS and early neurologic assessment of coma due to head injury. 2° However, pupillary response to light is often obscured by local trauma, previous surgery, or medications. Oculocephalic reflexes require movement of the head, which is almost always tightly secured until cervical spine injury has been excluded. The GCS score alone appears to be the best available method for neu-
6
James V. Winkler, Peter Rosen, and Edward J. Alfry
rologic assessment of depth of coma in the prehospital setting. This preliminary study suggests that the GCS score at the scene of injury has no prognostic value. However, recording GCS scores initially and again in the emergency department will provide a prehospital net change in the GCS score that could prove
useful for predicting outcome from severe head injury. An increase of the GCS score in the prehospital setting is frequently associated with a better prognosis, and those patients who continue to have a low GCS score with an increase of 2 or less by the time they arrive in the emergency department appear to have a substantially worse prognosis.
REFERENCES 1. Teasdale G, Jennett B: Assessment of coma and impaired consciousness. A practical scale. Lancet 1974; 2:81-84. 2. Jane JA, Rimel RW: Prognosis in head injury. Clin Neurosurg 1982; 29:346-352. 3. Seelig JM, Becker DP, Miller JD, et al: Traumatic acute subdural hematoma. Major mortality reduction in comatose patients treated within four hours. NEngl JMed 1981; 304:1511-1518. 4. Langfitt TW: Measuring the outcome from head injuries. J Neurosurg 1978; 48:673-678. 5. Bruce DA, Gennarelli TA, Langfitt TW: Resuscitation from coma due to head injury. Crit Care Med 1978; 6:254-269. 6. Jennett B, Teasdale G: Aspects of coma after head injury. Lancet 1977; 1:878-881. 7. Jennett B, Teasdale G, Fry J, et al: Treatment for severe head injury. J Neurosurg Psychol 1980; 43:289-295. 8. Gennarelli TA, Spielman GM, Langfitt TW, et al: Influence of the type of intracranial lesion on outcome from severe head injury. A multicenter study using a new classification system. J Neurosurg 1982; 56:26-32. 9. Young B, Rapp RP, Norton JH, et al: Early prediction of outcome in head-injured patients. J Neurosurg 1981; 54:300-303. 10. Jennett B, Bond M: Assessment of outcome after severe brain damage. A practical scale. Lancet 1975; 1:480-484. 11. Becker DP, Miller JD, Ward JD, et al: The outcome from severe head injury with early diagnosis
and intensive management. J Neurosurg 1977; 47:491-502. 12. Rimel RW, Jane JA, Edlich RF: An injury severity scale for comprehensive management of central nervous system trauma. JACEP 1979; 8:64-67. 13. Clifton GL, Grossman RG, Makela ME, et al: Neurological course and correlated computerized tomography findings after severe closed head injury. J Neurosurg 1980; 52:611-624. 14. Jennett B, Teasdale G, Braakman R, et al: Predicting outcome in individual patients after severe head injury. Lancet 1976; 1:1031-1034. 15. Rimel RW, Giordani B, Barth JT, et al: Disability caused by minor head injury. Neurosurgery 1981; 9:221-228. 16. Rimel RW, Giordani B, Barth JT, et al: Moderate head injury: Completing the spectrum of brain injury. Neurosurgery 1982; 11:344-351. 17. Braakman R, Gelpke G J, Habbema JD, et al: Systematic selection of prognostic features in patients with severe head injury. Neurosurgery 1980; 6:362-370. 18. Langfitt TW, Genarelli TA: Can outcome from head injury be improved? J Neurosurg 1982; 56:19-25. 19. Miller D J, Butterworth JF, Gudeman SK, et al: Further experience in the management of severe head injury. J Neurosurg 1981; 54:289-299. 20. Levati A, Farina ML, Vecchi G, et al: Prognosis of severe head injuries. JNeurosurg 1982; 57:779783.