12-09 Brain Death and PVS

Question 1

locked in syndrome

Answer 1

—fully consciousness
—damage to the base of the pons
—preservation of consciousness and vertical eye movements
—loss of all other voluntary movements.

Question 2

brain death definition and clincal signs

Answer 2

—irreversible cessation of function of a critical number of neurons in the cerebral hemispheres and brain stem (whole brain)

CLINICAL SIGNS: complete unresponsiveness, absent brain stem reflexes, apnea

Question 3

causes of brain death

Answer 3

primary:
—asphyxia in kids
—head trauma
—cardiac arrest
—intracranial hemorrhage

secondary:
—sequelae of incr ICP/transtentorial herniation

Question 4

Lazarus sign

Answer 4

—raise arms up and cross them across their chest

—may be present in brain dead pts

Question 5

reflexes in brain death

Answer 5

—limb tendon reflexes still present

—no CN reflexes

Question 6

clinical conditions that must be met to support irreversibility

Answer 6

—there is a known lesion
—there are no reversible metab/toxic etiologies
—there is no hypothermia

Question 7

confirmatory test dr. bernat advocates

Answer 7

blood flow test

Question 8

confirmatory tests of brain death

Answer 8

ELECTROPHYSIO
EEG + BAER + SSER
*brainsteam auditory evoked response
**somato-sensory ER

INTRACRANIAL BLOOD FLOW
—he talked about radionuclide angio most
—intracranial doppler

Question 9

Vegetative state definition

Answer 9

a. Unaware of self or environment
b. No voluntary behavioral response to stimuli
c. No demonstration of comprehension

d. Normal sleep-WAKE cycle
e. Preserved autonomic, respiratory, endocrine, cranial nerve functions
f. These patients are not dead

Question 10

PVS def

Answer 10

vegetative state lasting >1 month

Question 11

Vegetative State brain levels still working?

Answer 11

brain stem & hypothalamus
—thalamus and cortex out
—frontoparietal global workspace out
—appears similar to anesthesia on fMRI

Question 12

Minimally conscious state

Answer 12

Profound unresponsiveness but some evidence of responses, at least occasionally, that indicate awareness.
—can follow some commands, answer yes/no Qs, reach out and touch etc.
—studies have shown fMRI findings of cortical activation when pts asked to do linguistic task/imagine things (case of 23 y/o thought to be in VS)

Question 13

tx options in minimally conscious state

Answer 13

more tx options here
**“drill down to find etiology of the MCS”
—neuro-rehabilitation
—dopaminergic rxs (levodopa, dopamine agonists)
—zolpidem —> exerts DAergic effects on intralaminar —> nuclei of thalami
—? SSRI