Trauma / Critical care

Question 0

ICP waveforms P1, P2, P3: what do they represent

Answer 0

P1: percussion wave: arterial pulsation
P2: tidal wave, represents compliance (decreased leads to high wave)
P3: dicrotic: ao valve closure

Question 1

duret hemorrhages occur in what herniation

Answer 1

central

Question 2

goal cerebral perfusion pressure

Answer 2

> 60

Question 3

Dose of osmotic treatment for ICP (2 choiceS)

Answer 3

1. Mannitol 0.25-1g/kg bolus, can repeat q8

2. 23% NaCl 30 mL bolus

Question 4

what causes duret hemorrhages

Answer 4

shearing of basilar perforators

Question 5

type of herniation that causes midbrain findings and CN 3 pupil dilation

Answer 5

tentorial / uncal herniation

Question 6

what is kernohan’s notch phenomenon

Answer 6

compression of contralateral cerebral peduncle against tentorium with uncal herniation

Question 7

stroke scale scores that may be suggestive of increased risk of herniation with malignant ischemic stroke

Answer 7

left hem >20

rt hem >15

Question 8

Mild TBI / concussion, define three grade?

Answer 8

1. transient confusion < 15m, NO LOC
2. longer transient confusion > 15m, NO LOC
3. any LOC

Question 9

dose of steroids that can possibly used in traumatic spinal cord injury (not clearly beneficial)

Answer 9

< 3 hrs, 30mg/kg methylpred, then 5.4mg/kg/hour for 23h (longer if presenting from 3-8 hrs : 2 d)

Question 10

steroid dosing for cord compression

Answer 10

10-100mg dexamethasone, then 4mg q4H 3-5 d

Question 11

patient arouses but no awareness, eyes open and may track. There are diurnal/nocturnal cycles

Answer 11

persistent vegetative state

Question 12

mild to moderate reduced alertness, slow psychologic response to stimulation

Answer 12

obtundation

Question 13

arousal only with vigorous continuous stimulation

Answer 13

stupor

Question 14

no arousal

Answer 14

coma

Question 15

in persistent vegetative disease, what happens with day/night

Answer 15

preservation of cycles

Question 16

in cold calorics, what drives eyes toward cold stimulus vs nystagmus away

Answer 16

toward cold: brainstem only

saccadic component of nystagmus away (COWS: Cortical)

Question 17

if you get tonic deviation of eyes to cold water in cold calorics what is the issue

Answer 17

cortical lesion (you get brainstem drive only)

Question 18

cold calorics with no response indicates what

Answer 18

no cortical or brainstem response

Question 19

right way eyes look where

What happens with oculocephalics

Answer 19

frontal cortical lesions toward the lesion (not the weakness)
oculocephalics will overcome

Question 20

wrong way eyes look where and what lesion and what happens with oculocephalics

Answer 20

look toward weakness not lesion, as in with pontine lesions and this is due to a CN VI palsy and will not be overcome by oculocephalics

Question 21

what causes skew deviation of eyes

Answer 21

midbrain lesion

Question 22

what location of lesion causes ocular bobbing

Answer 22

pons lesion

Question 23

respiration pattern:

what causes cheyne strokes (2 types of lesions and expected motor responses)

Answer 23

bihemispheric or diencephalic lesions, can tell which based on whether hemiplegic or whether decorticate

Question 24

hyperventilation occurs in what type of lesion and what do you see for motor?

Answer 24

midbrain lesion causes decorticate posture

Question 25

what is decorticate posturing and where is lesion

Answer 25

arms flexed pointing to head due to involvement of red nucleus

Question 26

decerebrate posturing indicates a lesion where, what posture

Answer 26

arms down, not involving red nucleus, lesions below

Question 27

apneustic or cluster breathing and decerebrate posturing indicates lesion where

Answer 27

pontine

Question 28

where is lesion causing ataxic or frank apnea and no motor response

Answer 28

medulla

Question 29

cells very susceptible to hypoxic injury (5)

Answer 29

CA1 pyramidal cells in hippocampus cortical layers III and V purkinje cells/dentate GP

Question 30

man in barrel syndrome | what else may be present sx

Answer 30

transcortical motor aphasia | watershed infarct in ACA/MCA borderzone

Question 31

typical presentation of mca/pca watershed infarct

Answer 31

balint's syndrome and transcortical sensory aphasia

Question 32

what NSE level when may predict poor prognosis in coma | neuronal specific enolase

Answer 32

Day 1-3, NSE >33

Question 33

when is absent N20 response most predictive of bad prognosis in coma

Answer 33

day 1-3

Question 34

define parameters for brain death apnea test

Answer 34

if there is no resp drive with PaCO2 of 60 or 20mmHg above baseline

Question 35

what temp do you need for brain death exam

Answer 35

<36.5