ISE Trauma 4 (head trauma)

Question 1

remarks on head trauma

Answer 1

young adults and chidren - mvc
elderly - fall

Question 2

lower limit of autoregulation of CPP in humans

Answer 2

<60 mm Hg
below this, local control of cerebral blood flow cnnot be adjusted to maintain flow adequate for function

Question 3

In the absence of an ICP monitor, it is important to maintain

Answer 3

MAP ≥80 mm Hg
because low blood pressure in the setting of elevated ICP will result in a low CPP and brain injury

Question 4

intracranial pressure by age group

Answer 4

adults: <10-15 mmHg
young children: 3-7 mm Hg
infants: 1.5-6 mmHg

Question 5

types of brain herniation

Answer 5

uncal herniation
central transtentorial herniation
cerebellotonsillar herniation
upward transtetorial herniation

Question 6

uncacl herniation

Answer 6

most common
uncus of temporal lobe is displaced inferiorly through the medial edge of the tentorium
usually caused by an expanding lesion in the temporal lobe or lateral middle fossa

ipsilateral fixed and dilated pupil
contralateral motor paralysis

Question 7

central transtentorial herniation

Answer 7

occurs with midline lesions, such as lesions of the frontal or occipital lobes, or vertex

bilateral pinpoint pupils
bilateral Babiinski’s signs
increased muscle
decorticate posturing

Question 8

cerebellotonsillar herniation

Answer 8

occurs when the cerebellar tonsils herniate through the forament magnum

pinpoint pupils
flaccid paralysis
sudden death

Question 9

upward transtentorial hearniation

Answer 9

posterior fossa lesion

conjugate downward gaze with absence of vertical eye movements
pinpoint pupils

Question 10

regards on GCS

Answer 10

get the patient’s best score

Question 11

decorticate

Answer 11

upper extremity flexion
lower extremity extension

Question 12

decerebrate posturing

Answer 12

“we don’t celebrate”

arm extension and internal rotation
wrist and finger flexion
lower extremity extension and internal rotation

Question 13

means to control agitated patients with TBI

Answer 13

midazolam 1-2 mg IV
propofol 20 mg every 10 seconds

Question 14

New Orleans criteria

Answer 14

for GCS 15
Age >60y

headache
vomiting
seizure

intoxication
persistent antegrade amnesia
evidence of trauma above the clavicles

100% sensitive, but 5% specific in identifying patients who have an intracranial lesion on CT

Question 15

Canadian CT head rule

Answer 15

gcs 13-15
GCS <15 at 2h
Age ≥65y

> 1 ep of vomiting
retrograde amnesia >30 m

suspected open or depressed skull fracture
any sign of basal skull fracture

dangerous
mechanism
-fall >3ft
-struck as pedestrian
-fall >5 stairs

83% snesitive, but 38% specific in identification of patients who have an intracranial lesion on CT

Question 16

primary goals in head trauma

Answer 16

1. maintain cerebral perfusion and oxygenation by optimizing intravascular volume and ventilation
2. prevent secondary injury by correcting
   -hypoxia
   -hypercapnia
   -hyperglycemia
   -hyperthermia
   -anemia
   -hypoperfusion
3. recognize and treat elevated ICP
4. arrage for neurosurgical intervation to evacuate intracranial mass lesions
5. treat other life-threatening injuries

Question 17

remarks on hypotension and hypoxemia in head trauma

Answer 17

SBP <90 mmHg and hypoxemia PaO2 <60 mmHg are associated with a 150% increased risk in mortality

goals:
50-69y: SBP ≥100 mmHg
15-49, >70y: SBP ≥110 mmHg
CPP 60-70 mmHg

SpO2 >90%
PaO2>60 mmHg
PCO2 35-45 mmHg
Hgb ≥8 g/dL

normal saline for volume resuscitation

Question 18

remarks on sedatation in head trauma

Answer 18

sedation and analgesia may decrease baseline ICP and prevent transient rises in ICP attributed to agitation, coughing, or gagging from the ET tube

ketamine is not recommended as preintubation agent bec it can cause agitation in patients after trauma

Question 19

remarks on seizures in head trauma

Answer 19

administer prophylactic antiseizure for GCS ≤10, if patient has abn head CT, or if the patient had an acute seizure after the injury

phenytoin 18mg/kg IV at 25mg/min
levetiracetam

Question 20

remarks on mannitol in head trauma

Answer 20

Mannitol by repetitive bolus
(0.25-1 g/kg)
no dose-dependent effect, so it’s okay to begin at lower range of the suggested dose

in the setting of acute herniation, mannitol has been demonstrated to effectively reduce life-threatening elevations of ICP

alt:
hypertonic saline
3% sodium chloride, 250 mL over 30 mins
23.4% sodium chloride, 30 mL over 30 mins

Question 21

remarks on skull fractures

Answer 21

skull fractures that are open or depressed,
involve a sinus, or are
associated with pneumocephalus

should be given antibiotics:
vancomycin 1g IV, ceftriaxone 2g IV

Question 22

remarks on basilar skull fracture

Answer 22

most common:
petrous portion of the temporal bone,
the external auditory canal, and
the tympanic membrane

may involve 7th nerve palsy

antibiotic prophylaxis:
ceftriaxone 2g IV, vancom 1g iv

Question 23

contusion most commonly occur in the

Answer 23

subfrontal cortex
frontal and temporal lobes
occ in occipital oolobes

often associated with SAH

Question 24

Most common CT abnormality in patients with mod-to-severe TBI

Answer 24

SAH

CT scans performed 6-8 hours after injury are sensitive for detecting traumatic SAH

Question 25

remarks on subdural hematoma

Answer 25

hematoma formation bet dura mater and arachnoid

brains with extensive atrophy, such as in the elderly or in chronic alcoholics, are more susceptible to the development of acute subdural hematoma

children <2 y are also at increased risk of subdural hematoma

acute symptoms usually develop within 14 days of the injury
often the patient is unconsicous

crescent shape lesions that cross the suture line

Question 26

remarks on epidural hematoma

Answer 26

classic history:
significant blunt head trauma with LOC or altered sensorium, followed by a lucid period and subsequent rapid neurologic demise

Question 27

remarks on diffuse axonal injury

Answer 27

CT scan may appear normal, but class CT findings include punctuate hemorrhagic injury along the gray-white junction of the cerebral cortex and within the deep structures of the brain

Question 28

remarks on penetrating head injury

Answer 28

GCS>8 with reactive pupils have a 25% mortality risk

gcs <5, mortality approaches 100%

Question 29

mild tbi

Answer 29

concussion
confusion
amnesia
vomiting, headache
loss of consciouness

primary intervention is rest
“splinting the brain”
physical and neurologic rest past the acute 48-hour period shortens the duration of symptoms

Question 30

second impact syndrome

Answer 30

mortality 60-80%
rapid onset of cerebral edema due to a loss of autoregulation and ion imbalance (ion channel upregulation)