Introduction References Case
Outcome Annotated
Bibliography Questions
Mild
Traumatic Brain Injury in Sports
Case
Presentation
On the last
day of a glorious two week vacation, MP a 20 year old male novice skier
ended a great vacation in the wrong way. After several days of lessons,
MP had become over confident with his marginal skills and decided he
was ready for the back bowl, black diamonds. Unfortunately his instructors
never emphasized the need to wear a helmet nor did they teach by example.
At 40 mph, MP lost control on an ice patch and was launched head first
into a tree. The impact was significant, the stars were bright, and
MP lay unconscious for 1 to 3 minutes. By the time other skiers arrived
to help, MP was awake and alert, and other than a "goose egg"
on the top of his head, he claimed he was OK to ski down to the lodge.
At the bottom of the mountain, MP felt well except for a moderate headache.
When he said he had no appetite for lunch (which was unusual), his family
insisted he be seen in the emergency department before embarking on
the 12 hour trip home. In the ED, three hours after the accident, MP
had a blood pressure of 118/80, a pulse of 64, a respiratory rate of
14, a temperature of 37, and an oxygen saturation of 100% on room air.
His Glasgow coma scale score was 15, a small hematoma on his scalp without
surrounding tenderness or deformity, and a completely normal neurologic
examination. The examining physician determined that MP had not sustained
a significant injury and discharged him a prescription for ibuprofen
and a head injury sheet.
TOP
Mild Traumatic
Brain Injury in Sports
Introduction
Key Clinical
Questions
- Is a single Glasgow coma
scale (GCS) score predictive of the presence of a traumatic brain injury?
-
Are there historical or
physical findings that predict the presence of a traumatic brain injury?
-
Is there a role for plain
skull radiographs in the evaluation of patients with a MTBI?
-
Which patients with mild
traumatic brain injury (MTBI) require neuroimaging?
-
Can patients with a GCS
score of 15 and a normal head CT be safely discharged from the ED
without admission to the hospital for observation?
-
In patients with a GCS
of 15, what is the risk of developing the postconcussive syndrome?
In the United
States, approximately 1.6% of all emergency department (ED) visits are
for a head injury. Approximately 90% of these visits are for mild traumatic
brain injury (MTBI), and 10% for moderate or severe TBI. (1) TBI is
the leading cause of death among people less than 24 years. (2) Approximately
50% of patients who die from TBI arrive to the hospital alive; a number
which can potentially be decreased with early and aggressive interventions.
(3)
Head injury
and traumatic brain injury (TBI) are two distinct entities that are
often, but not necessarily, related. A head injury is best defined as
an injury that is clinically evident upon physical examination and is
recognized by the presence of ecchymoses, lacerations, deformities,
or cerebral spinal rhinorrhea or otorrhea.. Traumatic brain injury refers
to an injury to the brain itself and can occur without external signs
of trauma.
Is a single Glasgow coma scale (GCS) score predictive of the presence
of a traumatic brain injury?
Historically,
the most often used system for grading severity of brain injury is the
Glasgow Coma Scale (GCS) score which assesses eye opening, verbal function
(mental status), and motor function; a modified scale exists for nonverbal
children. (4) The GCS was developed in 1974 as a standardized clinical
scale allowing for reliable interobserver neurologic assessments of
TBI patients in coma. (5). The original studies applying the GCS score
as a tool for assessing outcome required that coma be present for at
least six hours. (5,6,7) The scale was not designed to diagnose patients
with mild or even moderate TBI nor was it intended to supplant a neurological
examination. Instead, the GCS was designed to provide an easy to use
assessment tool for serial evaluations by relatively inexperienced care
providers, and to facilitate communication between care providers on
rotating shifts.
A single isolated GCS score is of limited value, is insufficient to
determine the degree of parenchymal injury after trauma, and does not
have prognostic value. On the other hand, serial GCS scores are a valuable
clinical tool (when confounding factors such as drugs or alcohol are
absent). A low GCS score that remains low, or a high GCS that decreases,
predicts poorer outcomes than high GCS scores that remain high, or a
low GCS score that progressively improves. In one of the original multi-center
studies validating the score approximately 13% of patients who ultimately
were in coma had a GCS of 15 (note that at the time these studies were
done, CT was not available to aid in clinical decision making). (7)
The literature
refers to "mild" TBI (MTBI) as those patients with a GCS score
greater than 12. Some authors have suggested that patients with a GCS
of 13 be excluded from the "mild" category and placed into
the "moderate" risk group due to their high incidence lesions
requiring neurosurgical intervention. (8,9) The key for the clinician
is to not overly rely on a GCS score, but instead to use the GCS score
in conjunction with a relevant neurologic exam to assess head injured
patients for TBI.
Are there historical or physical findings that predict the presence
of a traumatic brain injury?
On the initial
encounter, it is not possible to accurately determine the degree of
brain injury that a head injured patient has sustained. In patients
with blunt trauma who appear to have sustained a minor head injury,
the only historical parameters proven to be useful in identifying patients
with lesions requiring neurosurgical intervention are loss of consciousness
(LOC) and/or amnesia. (10, 11, 12) A history of headaches, seizures,
nausea, vomiting, dizziness, age over 60, or evidence of trauma above
the clavicle have not been found to be independent predictors of an
intracranial lesion. However, the absence of all of the above has been
reported to be 100% sensitive in excluding an injury requiring neurosurgical
intervention even when LOC has occurred. (11) History of anti-coagulant
therapy or hemophilia are additional historical findings that may be
associated with an increased risk for an intracranial event.
The presence
of focal neurologic findings or an altered mental status is predictive
of significant lesions (13, 14), though conversely the absence of findings
does not eliminate the possibility that an injury has occurred. (15)
When performing the neurologic examination, particular attention must
be paid to cranial nerves III, IV and VI. Papilledema is a late finding
in increased intracranial pressure (ICP) and thus is not seen in acute
head injury. The pupil exam consists of determining pupil size, symmetry,
and reactivity to light. Mass effect from edema or an expanding lesion
may result in a unilateral, fixed and dilated pupil. Bilaterally dilated
and fixed pupils are consistent with brain stem injury. Hypoxemia, hypotension,
and hypothermia are associated with dilated pupil size and abnormal
reactivity, making it necessary to resuscitate and stabilize the patient
before accurate pupillary assessment can occur. (16)
An assessment of cognitive function may be helpful in select cases in
that it provides an important baseline in the patient's evaluation.
Cognitive function is only superficially assessed in the GCS score through
the patient's verbal response. In MTBI, it has not been shown to be
predictive of parenchymal injury demonstrable on head CT. (9, 17)
Is there a role for plain skull radiographs in the evaluation of patients
with a MTBI?
Hofman et al performed a meta-analysis of the literature examining the
role of plain films in evaluating patients with TBI. (18) Two hundred
studies were reviewed, and 20 were identified to have sufficient merit
to be included in the meta-analysis. The authors reported that the sensitivity
of skull fracture in detecting patients with an intracranial lesion
ranged from .13 to .75, with a specificity from .91 to .995. They discussed
their concern about both selection bias and verification bias contributing
to the high specificity reported by the studies, i.e., patients were
more likely to receive a CT if their GCS was less than 15 or if they
had a positive plain film. Using the combined results for sensitivity,
specificity, and prevalence the authors reported the positive predictive
value of a skull fracture for the diagnosis of an intracranial lesion
as .41 and the negative predictive value as .94. These findings suggest
that the presence of a skull fracture increases the probability of an
intracranial lesion fivefold. However, the meta-analysis concluded that
though a fracture demonstrated on plain film increased the likelihood
of an intracranial lesion, its low sensitivity precluded its use to
rule out the diagnosis of an intracranial hemorrhage and thus is of
limited clinical value in risk stratification for brain injury.
Which patients with mild traumatic brain injury (MTBI) require neuroimaging?
Patients with
blunt head injury who do not sustain LOC or post traumatic amnesia are
at almost no risk of significant intracranial injury requiring a diagnosis
in the ED and do not need neuroimaging in the ED. On the other hand,
approximately 10% of patients with a history of LOC and a GCS score
of 15 will have an acute lesion on noncontrast head CT; less than one
per cent will have a lesion in need of a neurosurgical intervention.
(11) The literature does not clearly state which patients with intracranial
lesions deteriorate, nor is it clear about the predictive value of intracranial
lesions in predicting the development of postconcussive syndrome.
Well designed
studies and evidence based practice guidelines recommend that patients
with blunt head trauma who experienced LOC or posttraumatic amnesia,
with a GCS score of 15 and a normal neurologic exam do not need a head
CT in the ED if they do not have headache, vomiting, age > 60, drug
or ETOH intoxication, deficits in short-term memory, physical evidence
of trauma above the clavicle, or seizure. (11, 19) Patients with any
of the above findings, and those with a GCS score below 15, should be
considered for a head CT.
In patients with a GCS of 15, what is the risk of developing postconcussive
syndrome?
The postconcussive
syndrome (PCS) refers to a symptom complex experienced by many patients
after mild TBI. In general, PCS is comprised of somatic, cognitive,
and affective symptoms. Common symptoms include headache, dizziness
/ vertigo, difficulty concentrating, and depression. Approximately 30%
of patients with mild TBI will have symptoms at 3 months post-injury,
and up to 15% will continue to be symptomatic at one year post injury.
(20. 21) It appears that well motivated, young, male patients are at
the lowest risk of developing the PCS and that females, those over 55
years of age, or patients that experienced prolonged posttraumatic amnesia
are at a higher risk of developing the PCS. (22) Despite the emerging
consensus that somatic and cognitive deficits result from mild TBI,
physiogenesis versus psychogenesis of symptoms is debated especially
when symptoms persist for more than three months.
When managing a patient with mild TBI, it is important to take the time
to advise them of the potential sequelae of the injury in that it may
significantly assuage their anxiety of permanent damage. A referral
to a specialist with expertise in caring for these patients may be helpful
for the patient's prognosis. Recovery appears to be linked not only
to the underlying lesion but also to psychosocial issues in the patient's
life. Consequently, access to a multidisciplinary resource may provide
the patient with the most comprehensive support services to assist in
recovery.
Can patients with a GCS score of 15 and a normal head CT be safely discharged
from the ED without admission to the hospital for observation?
Over the past decade, access to neuroimaging has resulted in a decline
in the number of MTBI patients admitted to the hospital for observation
without a reported increase in adverse outcomes. (23) The question is,
at what point in time from the injury is it safe to discharge the patient.
Most of the literature addressing this question is limited by its methodology.
For example, Lee and colleagues prospectively followed 1812 patients
who were discharged from the hospital with a GCS of 15 at 3, 7, 30,
and 60 days. Twenty-eight patients deteriorated, 57% within the first
24 hours; 23 of the 28 who deteriorated required a neurosurgical intervention.
Unfortunately, most of the patients did not have initial CTs. (24) Shackford
et al reported on 933 patients with normal neurologic examinations and
normal head CTs who were admitted to the hospital for observation. (25)
They reported that 2% of this group required intubation, i.e., deteriorated,
though none required neurosurgical intervention. Unfortunately, the
authors do not provide the timing of the deterioration or other specific
information related to the cases. Nagy et al prospectively studied 1170
trauma center patients all of whom had a CT and were admitted for 24
hours of observation. (26) Similar to the studies already described,
3% of the patients had a positive CT, and 0.3 % required neurosurgery.
Despite the study design's spectrum bias favoring sicker patients, no
patient deteriorated. Dunham analyzed data from 2587 trauma center patients;
no patient with a negative CT deteriorated and all patients who did
deteriorate did so within 4 hours of arrival at the trauma center. (27)
Jeret prospectively studied 712 patients, 67 (9.4%) of whom had a positive
CT. One patient who initially had a normal exam deteriorated within
"several hours" of arriving in the ED, at which point a CT
disclosed a left temporal contusion; by 6 hours he was lethargic and
had a craniotomy. (28)
Based on the
best available evidence, patients with a GCS score of 15 and a negative
head CT can be safely discharged home with a reliable adult. Although
the safety of home observation has been established in this subset of
patients, patients with TBI may not remember their discharge instructions
emphasizing the need to not only give patients written instructions,
but also to provide important information that will impact the patient
during the recovery period to a family member or friend.
Key Learning Points:
1. A single Glasgow coma
scale (GCS) score is not predictive of the presence of a traumatic
brain injury thus patients who have sustained a head injury should
have serial exams performed over the first several hours post-injury.
2. Loss of consciousness
and / or post-traumatic amnesia suggest the potential for a traumatic
brain injury and drive the need for either a neuroimaging study or
a prolonged period of observation. The presence of a focal neurologic
deficit or signs of a basilar skull fracture are associated with a
traumatic brain injury and thus their presence requires neuroimaging
to assess the degree of injury.
3. Normal plain skull radiographs
do not decrease the possibility of a traumatic brain injury and therefore
should not be used in risk stratifying patients with head injuries.
4. A head CT is not indicated
in head injury patients with a GCS score of 15 and no history of loss
of consciousness or post-traumatic amnesia. In those patients with
loss of consciousness or post traumatic amnesia, a head CT is not
indicated if there is no headache, vomiting, age > 60, drug or
ETOH intoxication, deficits in short-term memory, physical evidence
of trauma above the clavicle, or seizure.
5. There are no good predictors
of which head injured patients with a GCS of 15 are at risk to develop
the postconcussive syndrome thus all patients with a head injury should
be given information regarding PCS.
6. Patients with MTBI who
are six hours post-injury, have a normal clinical examination, and
who have a head CT that does not demonstrate acute injury can be safely
discharged from the emergency department. Patients can be discharged
after a shorter period of observation if under the care of a responsible
third party.
TOP
Mild
Traumatic Brain Injury in Sports
Reference
List
1. Jager T,
Weiss H, Coben J, Pepe P. Traumatic brainin injuries evaluated in
U.S. emergency departments, 1992-1994. Acad Emerg Med. 2000; 7:134-140.
2. White BC,
Krause GS: Brain injury and repair mechanisms: The potential for pharmacologic
therapy in closed head trauma: Ann Emerg Med 22:970, 1993.
3. Guidelines
for the Management of Severe Head Injury: Brain Trauma Foundation,
NY 1995.
4. Chameides,
L, Hazinski M, eds. Textbood of Pediatric Advanced Life Support. American
Heart Association. 1994,8:3.
5. Teasdale
G, Jennett B. Assessment of coma and impaired consciousness; a practical
scale. Lancet 1974; 4:81-83.
6. Teasdale
G, Jennett B. Assessment and prognosis of coma after head injury.
Acta Neurochir 1976; 34:45-55.
7. Jennett
B, Teasdale G, Galbraith S, et al. Severe head injuries in three countries.
J Neurol Neurosurg Psych 1977; 40:291-298.
8. Stein SC,
Ross SE: Mild head injury: A plea for routine early CT scanning. J
Trauma 33:11, 1992
9. Williams
D, Levin M, Howard E: Mild head injury classification. Neurosurg 27;422,
1990.
10. Masters
SJ, McClean PM Arcarese JS et al. Skull x-ray examination after head
trauma. N Engl J Med 1987; 316: 84-90.
11. Haydel,
MJ, Preston, CA, Mills, TJ, et al. Indications for computed tomography
in patients with minor head injury. N Engl J Med. 2000; 343:100-105.
12. Stiell
I, Wells G, Vandemheen K, et al. The Candadian CT head rule for patients
with minor head injury. Lancet 2001; 357:1391-1396.
13. Shackford,
SA, Wald, SL, Ross, SE, et al. The clinical utility of computed tomographic
scanning and neurologic examination in the management of patients
with minor head injuries. J Trauma. 1992; 33: 385-394.
14. Nagurney,
JT, Borczuk, P, Thomas, SH. Elder patients with closed head trauma:
A comparison with nonelder patients. Acad Emerg Med. 1998; 5:678-684.
15. Vilke,
GM, Chan, TC, Guss, DA. Use of a complete neurological examination
to screen for significant intracranial abnormalities in minor head
injury. Amer J Emerg Med. 2000; 18:159-163.
16. Meyer
S, Gibb T, Jurkovich G: Evaluation and significance of the pupillary
light reflex in trauma patients. Ann Emerg Med 22:1052-1057, 1993.
17. Jeret
JS, Mandell, M, Anziska, B, et al. Clinical predictors of abnormality
disclosed by computed tomography after mild head trauma. Neurosurg.
1993; 32:9-16.
18. Hofman,
PAM, Nelemans, P, Kemerink, GJ, et al. Value of radiological diagnosis
of skull fracture in the management of mild head injury: meta-analysis.
J Neurol Neurosurg Psych. 2000; 68:416-422.
19. American
College of Emergency Physicians. Clinical policy: Emergency department
management of mild traumatic brain injury (MTBI) in adults. Ann Emerg
Med 2002; 40:231-249.
20. Alves
W, Macciocchi S, Barth J: Postconcussive symptoms after uncomplicated
mild head injury. J Head with isolated skull fracture: What are the
clinical characteristics and do they require hospitalization? Ann
Emerg Med 1997; 30:253-258.
21. Rimel
R, Giordani B, Barth J, et al: Disability caused by minor head injury.
Neurosurg 1981; 9:221-230.
22. Rutherford
WH, Merret JD, McDonald JR: Symptoms at one year following concussion
from minor head injuries. Injury 1978; 10:225.
23. Thurman
D, Guerrero J. Trends in hospitalization associated with traumatic
brain injury. JAMA 1999; 282:954-957.
24. Lee, ST,
Liu, TN, Wong, CW, et al. Relative risk of deterioration after mild
closed head injury. Acta Neurochirurg. 1995; 135:136-140.
25. Shackford,
SA, Wald, SL, Ross, SE, et al. The clinical utility of computed tomographic
scanning and neurologic examination in the management of patients
with minor head injuries. J Trauma. 1992; 33: 385-394.
26. Nagy,
KK, Joseph, KT, Krosner, SM, et al. The utility of head computed tomography
after minimal head injury. J Trauma Injury Infect Crit Care. 1999;
46:268-273.
27. Dunham,
CM, Coates, S, Cooper, C. Compelling evidence for discretionary brain
computed tomographic imaging in those patients with mild cognitive
impairment after blunt trauma. J Trauma Injury Infect Crit Care. 1996;
41:679-686.
28. Jeret
JS, Mandell, M, Anziska, B, et al. Clinical predictors of abnormality
disclosed by computed tomography after mild head trauma. Neurosurg.
1993; 32:9-16.
Mild
Traumatic Brain Injury in Sports
Outcome
of Case
On the way to
the airport, MP's headache become progressively worse; he became confused
then lethargic; he vomited twice and then had a generalized tonic clonic
seizure. He was rushed to the emergency department and arrived with
a GCS score of 6: An emergent head CT showed a large frontal subdural,
and a small occipial intraparenchymal hemorrhage. MP was taken to the
operating room for evacuation of the subdural and recovered without
significant sequelae; however, he frequently has headaches and his family
claims that his personality "is different" though they are
unable to characterize the change better.
MP always wears
a helmet now when he skies.
TOP
Mild Traumatic
Brain Injury in Sports
Annotated
Bibliography
1. Haydel, MJ, Preston,
CA, Mills, TJ, et al. Indications for computed tomography in patients
with minor head injury. N Engl J Med. 2000; 343:100-105.
A prospective study with
two phases: Phase 1 had 520 patients and was used to develop a prediction
rule for MTBI in patients with a GCS of 15 and a history of loss of
consciousness or post traumatic amnesia. Phase II was a validation
study with 909 patients. Overall, 6.5% of patients had a positive
CT, .4% with a neurosurgical lesion. Seven predictors of abnormal
CT were identified: headache, vomiting, age over 60, drug or ETOH
intoxication, deficits in short-term memory, physical evidence of
trauma above the clavicle, seizure. Absence of all 7 had 100% negative
predictive value. The studies only weakness was that patients were
not followed-up after discharge.
2. Hofman, PAM, Nelemans,
P, Kemerink, GJ, et al. Value of radiological diagnosis of skull fracture
in the management of mild head injury: meta-analysis. J Neurol Neurosurg
Psych. 2000; 68:416-422.
A meta-analysis of 20 studies
looking at the role of plain film radiographs in TBI. The outcome
measure used was skull fracture and intracranial hemorrhage. Thirteen
studies documented both outcome measures and reported as an aggregate
that 44% of patients with an acute traumatic brain lesion has a skull
fracture, i.e, 56% with an intracranial lesion did not have a fracture.
The authors concluded that a skull fracture increases the predictive
value of an intracranial hemorrhage but the absence of a fracture
can not be used as a surrogate to exclude a traumatic lesion.
3. Jeret JS, Mandell,
M, Anziska, B, et al. Clinical predictors of abnormality disclosed
by computed tomography after mild head trauma. Neurosurg. 1993; 32:9-16.
A prospective study of
712 consecutive trauma patients with a GCS of 15. The outcome measure
used was an abnormal CT. The authors found that 9.4% of patients had
an acute traumatic brain lesion and that .3% required neurosurgery.
They reported that neither the neuro exam, digit span, nor object
recall predicted which patients would have a neurosurgical lesion.
4. Livingston D, Lavery
R, Passannante M, et a. Emergency department discharge of patients
with a negative cranial computed tomography scan after minimal head
injury. Ann Surg 2000; 232:126-132
This paper had the right
idea but unfortunately its methodology was flawed and therefore its
results suspect. The study included 2152 consecutive patients with
a GCS of 14-15. A standardized physical and neuro exam was performed.
The authors report a negative predictive value of a normal head CT
as 99.7%. This paper's weaknesses include: the timing from injury
to CT was not recorded; group of patients who deteriorated was not
well described though appears that clinical course was predicted early
on (GCS 14, etc); the data analysis is not presented clearly; and
a negative predictive value is the wrong test for reporting findings.
5. Masters SJ, McClean
PM Arcarese JS et al. Skull x-ray examination after head trauma. N
Engl J Med 1987; 316: 84-90.
This is a classic paper
that has flawed methodology but stimulated tremendous interest in
the diagnosis of TBI. The authors developed a management strategy
based on the review of the literature and then applied it to 7035
patients. They categorized patients into low, medium, and high risk
subsets and made recommendations that changed the way clinicians approached
the head injured patient. The papers weaknesses include: 48% of patients
were lost to follow-up; the GCS score was not reported; it did not
address the significance of CT findings.
6. Nagurney, JT, Borczuk,
P, Thomas, SH. Elder patients with closed head trauma: A comparison
with nonelder patients. Acad Emerg Med. 1998; 5:678-684.
A retrospective review
of 1649 patients. Reported that a focally abnormal neurologic exam
imparted a risk ratio for an abnormal CT of 4.4 in the elderly (older
than 60) and 7.75 in the young. The papers weaknesses include: GCS
score was not reported and old neurologic lesions were not separated
from new ones.
7. Nagy, KK, Joseph,
KT, Krosner, SM, et al. The utility of head computed tomography after
minimal head injury. J Trauma Injury Infect Crit Care. 1999; 46:268-273.
A retrospective review
of 1170 patients all of whom had a CT and were admitted for 24 hours
observation. No patient with a normal head CT deteriorated and therefore
the authors recommended that these patients can be safely discharged
without the need for admission and observation.
8. Rimel R, Giordani
B, Barth J, et al: Disability caused by minor head injury. Neurosurg
9;221, 1981.
A classic study which obtained
three month followed-up on mild TBI patients who had been hospitalized
for observation. They reported that 79% complained of persisting headaches,
59% of memory dysfunction, and that 33% of patients had not returned
to work. They did not find ongoing litigation to be a significant
predictor of PCS, however, they did report that patients with unskilled
jobs had a higher incidence of PCS at three months while patients
with executive or managerial positions had a higher incidence of returning
to work.
9. Stiell I, Wells G, Vandemheen K, et al. The Canadian CT head
rule for patients with minor head injury. Lancet 2001; 357:1391-1396.
A derivation study of a
prospective cohort of 3121 TBI patients with a GCS of 15; all patients
had a positive LOC or post traumatic amnesia. 8% had a positive CT;
1% required a neurosurgical intervention. The authors derived a CT
head rule with 5 high risk predictors: failure to reach GCS 15 within
2 hours, suspected open skull fracture, sign of basal skull fracture,
vomiting more than once, age >64. The high risk factors were 100%
sensitive for predicting the need for neurosurgery and their application
would decrease the need for head CT by 68%. The study's weaknesses
include: only 67% of patients were scanned; 33% had a structured assessment
survey for clinically important lesion at 14 days post discharge;
only 172 patients who did not have a CT were followed-up (randomly
selected). Of note, solitary contusions <5mm, localized SAH <1mm,
smear subdural < 4 mm thick, isolated pneumocephaly, closed depressed
skull fracture not through the inner table were not considered clinically
important (based on survey consensus).
Mild
Traumatic Brain Injury in Sports
Questions
1. A skier
hits his head on a tree with loss of consciousness for one minute. When
the ski patrol arrives 3 minutes after the accident, his GCS score is
8 (opens his eyes only to pain; mumbles with no comprehensible speech).
Which of the following is correct?
a. The patient
has a severe brain injury
b. The patient has a bad prognosis
c. The presence of brain injury or prognosis can not be determined
2. Which
of the following is the most commonly affected cranial nerve in traumatic
brain injuries?
a. II
b. III
c. IV
d. VI
e. VII
3. A patient
with a head injury with loss of consciousness has a GCS score of 15
in the ED. Plain skull radiographs are obtained and are normal. What
per cent of these patients will have an acute traumatic lesion visualized
on head CT.
a. 10%
b. 20%
c. 30%
d. 40%
e. 50%
4. A 28 year
old patient sustains a head injury with loss of consciousness. In the
ED, his GCS score is 15; there is no headache, vomiting, seizure, intoxication,
altered mental status, or physical evidence of trauma. What is likelihood
of this patient having an acute traumatic brain lesion visualized on
CT?
a. 0%
b. 3%
c. 5%
d. 10%
e. 20%
5. Which
of the following is true of the postconcussive syndrome after a MTBI:
a. It is more likely to
develop if the patient is involved in accident related litigation
b. It is reported in up to 80% of patients in the first week post
injury
c. It rarely involves problems with concentration
d. It frequently persists after three months
1. C
A single GCS score, particularly immediately after an the injury is
neither predictive of the degree of injury nor of prognosis. The original
studies on the GCS score were performed on patients with severe traumatic
brain injuries who were at least six hours out from the trauma.
2. D
The sixth cranial nerve is the longest intracranial nerve and therefore
at greatest risk for injury from either direct trauma or from mass occupying
lesions / edema. The VI cranial nerve innervates the lateral rectus
and therefore head trauma patients should be examined for diplopia,
especially at far lateral gaze.
3. A
Plain skull films, when normal, are not helpful in predicting the presence
of an underlying traumatic brain injury and therefore can not be used
to risk stratify patients with head injury. Fifty percent of patients
with a documented acute traumatic brain injury have a normal skull radiograph.
Ten percent of MTBI patients with a GCS score of 15 have an acute traumatic
brain injury on CT though less than 1% have a neurosurgical lesion.
Of the 10% with an acute lesion, 50% have a normal skull radiograph;
on the other hand, the presence of a skull fracture on plain film radiograph
significantly increases the likelihood that there is a traumatic brain
lesion.
4. A
A well designed prospective study with a validation phase has conclusively
demonstrated that a head CT is not necessary in the MTBI patient who
has a GCS of 15, is less than 60 years old, and does not have evidence
of trauma above the clavicle, seizure, vomiting, deficits in short-term
memory, intoxication, or headache. It is estimated that using these
criteria would decrease the use of CT by at least 20% without imposing
any risk to missing a significant traumatic brain lesion.
5. A The
postconcussive syndrome (PCS) refers to a symptom complex experienced
by many patients after mild TBI. Common symptoms include headache, dizziness,
difficulty concentrating, depression, peripheral vestibular system dysfunction.
Approximately 30% of patients with mild TBI will have symptoms at 3
months post-injury; it is rare, but possible, for symptoms to persist
longer. It appears that well motivated, young, male patients are at
the lowest risk of developing the PCS, and recovery appears to be linked
not only to the underlying lesion but also to psychosocial issues in
the patient's life. Ongoing litigation has not been demonstrated to
predict the development or persistence of PCS.
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