Trauma / ICU

Question 1

Types of Herniation (4)

Answer 1

Question 2

High-output Heart failure + increased head circumference in neonate = what and why?

what do you do about it?

Answer 2

1. Vein of galen malformation (venous hypertension + compression of aqueduct of sylivis)
2. Cardiac sx = large left-to-right shunting through cerebral AV fistula
3. Embolization of cerebral vein

Question 3

Typical threshold for ICP that can lead to concern and why

Answer 3

at > 20 mmHg, CSF is shiften to spinal subarachnoid space

Question 4

Equations:

Mean aterial pressure
Central perfusion pressure
Cerebral blood flow

Answer 4

MAP= diastolic BP + 1/3 (SBP-DBP)

CPP = MAP - ICP

CBF = CPP / CVR

Question 5

What is P1, P2, and P3?

Answer 5

P1 = Percussion wave (represents arterial pulsation)

P2 = tidal wave (represents intracranial compliance)

P3 = dicrotic wave (represents aortic valve closure)

Question 6

What does this signify?

Answer 6

P2 > P1

decreased intracranial compliance

Question 7

Trauma patient is unable to move eyes up.

What is this called?
what does it signify?

Answer 7

Perinaud’s phenomenon

injury to superior calliculus

Question 8

Patient with signs of uncal herniation also develops ipsilateral weakness

What is this called?
what causes this?
name another possible finding

Answer 8

Kernahan’s notch phenomenon:

False-localizing sign due to compression of contralateral cerebral peduncle to tentoral edge

can also rarely have IL CN III weakness

Question 9

Herniation syndromes:

1. Contralateral leg weakness
2. pupillary dilation
3. 1. Rostrocaudal deterioration
   2. Duret’s hemorrhages
   3. diabetes insipidis
   4. bilateral occpitial infarction
4. 1. Decreased LOC + cardiac / respiratory abnormalities

Answer 9

1. CL leg weakness = subfalcine herniation (due to compression of ACA)
2. Pupillary dilation = Uncal herniation (due to compression of CN III)
3. Central / diencephalic herniation
   
   1. Rostracaudal deterioration
   2. duret’s hemorrhages (due to stretching/shearing of basilar perforators)
   3. DI (due to pituitary stalk shearing)
   4. Bilateral occipital infarcts (due to PCA compression)
4. tonsillar herniation (sx due to compression of lower brain stem and upper cervical cord)

Question 10

What herniation syndrome does this make you think of?

Answer 10

Duret’s hemorrhages

Central (diencephalic) herniation

Question 11

Factors that increase risk of herniation in stroke patients

(5)

Answer 11

1. hypodensity in > 50% of MCA territory
2. early nausea / vomiting
3. NIH scale > 20 (left hemisphere)
4. NIH scale > 15 (right hemisphere)
5. MCA + either ACA or PCA involvement

Question 12

Conservative (i.e. non medical, non surgical) management for increased ICP

(6)

Answer 12

1. Head of bed > 30 degrees
2. Head midline
3. Pain / Temperature control
4. Goal metrics
   
   1. ICP <20 mm Hg
   2. CPP > 60 mm HG
5. hyperventilation (goal pCO2 30-35 mmHg)

Question 13

lab value contraindicating Mannitol for increased ICP

Answer 13

osmolar gap >10

Osmolar gap = Measured osmolality (MO) - calculated osmolality (CO)

CO = (2xNa + (BUN/2.8) + (Glucose / 18) + (ethanol / 3.7))

Question 14

Glasgow coma scale and threshold for Mild, moderate, and severe injury

Answer 14

Mild = 13-15

Moderate = 9-12

Severe =/<8

Question 15

What type of injury does this resulf from

Answer 15

DAI of corpus callosum

acceleration / decelleration injury

Question 16

Return to play guidelines for concussion

Answer 16

Grade 1: confusion <15 minutes
Grade 2: confusion > 15 minutes
Grade 3: ANY LoC

Question 17

Cauda Equina syndrome versus conus medullaris syndrome

Radicular pain:
motor Weakness:
Sensory Distribution:
Reflexes:
Bladder symptoms:
Impotence:

Answer 17

Question 18

Treatment for bradycardia in patient with acute spinal cord compression

Answer 18

Atropine

Question 19

Eye findings in TBI and their signifiers:

Pupils mid-position and fixed (2)
Pupils fixed and dilated (3)
Pinpoint pupils (3)
Gaze preference away from paretic side
Gaze preferene toward paretic side
Skew deviation
ocular bobbing

Answer 19

1. Mid-position and fixed
   
   1. sympathetic / parasympathetic disruption (midbrain lesion)
   2. Drug induced (atropine)
2. Fixed and dilated
   
   1. extensive medullary lesion
   2. hypothermia
   3. barbituates
3. Pinpoint
   
   1. sympathetic dysruption but preserved parasympathetic
   2. pons or higher lesion (disruption of dorsal long fasciculus)
   3. narcotics
4. Gaze AWAY FROM paretic side
   
   1. pontine / thalamic lesion
   2. (oculocephalic maneuver WILL NOT overcome preference)
5. Gaze TOWARD paretic side
   
   1. frontal cortical lesion
   2. Oculocephalic WILL overcome preference
6. Skew deviation
   
   1. midbrain
7. ocular bobbing
   
   1. pons

Question 20

Brain lesions and relative respiratory / motor responses

Answer 20

Question 21

TBI patient with this imaging finding

Answer 21

Cortical Ribboning (hypoxia)

Question 22

TBI patient with this imaging finding

Answer 22

Basal ganglia injury (hypoxia)

Question 23

TBI patient with this imaging finding

Answer 23

Border zone injury (hypoxia)

1/2

Question 24

TBI patient with this imaging finding

Answer 24

Border zone injury (hypoxia)

2/2

Question 25

Predictors of poor outcome in TBI ``` Day 1 (2) Day 1-3 (2) Day 3 (2) ```

Answer 25

* Day 1 * Myoclonus * Status epilepticus * Day 1-3 * absent N20 on SSEP * Neuron-specific enolase (NSE) \> 33 ug/L * Day 3 * absent pupil / corneal reflexes * Extensor or absent motor responses

Question 26

before initiating brain death exam, must unsure the following (7)

Answer 26

1. Irreversible coma with known cause 2. neuroimaging explains coma 3. Absence of any CNS suppression (barbituates must be \<10 ug/mL) 4. absence of severe acit-base, electrolyte, or endocrine abnormality 5. Normothermia 6. normotension (SBP \>100 mmHg) 7. NO spontaneous respirations

Question 27

Steps of brain-death exam 1. Exam (8) 2. 3. 4. 5. Brain death criteria met if (2) | (after determining if patient meets criteria to start exam)

Answer 27

1. Exam 1. pupils (midsize or dilated), and non-reactive to light 2. (-) corneal reflex 3. (-) oculocephalic reflex (if C-spine isn't injured) 4. (-) doll's eye 5. (-) facial movement to noxious stimuli 6. (-) gag 7. (-) cough 8. (-) motor response to noxious stim in all extremities 1. Spinally mediated reflexes don't prevent diagnosis of brain death) 2. Ventilator adjusted to provide normal hypercarbia (paCO2 35-45 mmHg) 3. Pre-oxygenate patient with 100% fiO2 for \>10 minutes (goal Pa O2 \>200 mmHg) 4. Disconnect ventilator but provide O2 via suction catheter at level of carina 5. Brain death met if: 1. No spontaneous respirations 2. ABG drawn at 8-10 minutes \>60 mmHg or 20 mmHg rise from normal baseline

Question 28

When to abort Brain death exam (3)

Answer 28

1. hypotension (SBP decreases below 90 mmHg) 2. O2 sats \<85% for \>30 seconds (may retry after reoxygenation) 3. Spontaneous respirations are seen

Question 29

Ancillary test to determine brain death and expected results (5)

Answer 29

1. SSEP 1. Bilateral anbsence of N20-P22 response with median nerve stim 2. EEG 1. No electrical activity (EEG must be at least 30 minutes) 3. Cerebral angiography 1. No intracerebral filling at level of carotid bifurcation or CoW 4. Transcranial doppler (TCD) 1. small systolic peaks in early systole without diastolic flow or reverberating flow 5. Nuclear studies 1. no uptake of isotope in brain parenchyma ("hollow skull phenomenon")

Question 30

MRI changes during bleed and time frame for each Hyperacute: Acute: Early Subacute: Late subacute: Chronic:

Answer 30

"I bleed, I die, bleed die, bleed bleed, Die Die" Hyperacute (\<24 hours) * T1 Isointense, T2 Bright Acute (1-3 days) * T1 isointense, T2 Dark Early subacute (3-7 days) * T1 Bright, T2 Dark Subacute (7-14 days) * T1 Bright, T2 bright Chronic (\>14 days) * T1 dark, T2 dark

Question 31

Patient presents with hypertensive Emergency what is the goal reduction in BP? How does this change if the patient has had a stroke?

Answer 31

Goal reduction * 10-20% reduction in first hour * 5-15% reduction over next 23 hours Stroke: * Patients shouldn't have reduciton in BP for 3 days unless * they are receiving tPA and have BP \> 185/100 * BP \>220/120

Question 32

patient is admitted to ICU with subarachnoid hemorrhage What is the leading cause of death? what are two factors that increase risk?

Answer 32

Vasospasm (3-4 days after hemorrhage) Increase risk: Severity of bleed closeness to intracranial vessels

Question 33

Patient presents with recurrent headaches following TBI which is worse when sitting upward What is the best test to determine cause?

Answer 33

MRI with contrast | (looking for pachymeningial enhancement suggestive of CSF leak)

Question 34

Features of LeFort Fractures Common structure broken Unique features of Type I Type II type III

Answer 34

Common structure: Pterygoid process * Type I: * lateral margin of nasal fossa * "floating Palate" * Type II * Inferior orbital rim * "floating maxilla" * Type III * Zygomatic Arch * "floating face"

Question 35

Normal Cerebral Perfusion Pressure (CPP)

Answer 35

80 mmHg