(37) Coma Flashcards Preview

Neuro Block 2 > (37) Coma > Flashcards

Flashcards in (37) Coma Deck (39):
1

lethargy vs hyperinsomnia

lethargy = sleepy but easily aroused
hypersomnia = excessively sleepy but normal cognition when awakened

2

obduntation vs stupor

obduntation = mental blunting with decreased alertness

stupor = eye open only after vigorous stimulation and then go back to deep sleep

3

coma vs stupor

stupor = eye open only after vigorous stimulation and then go back to deep sleep

coma = eyes remain closed even after vigorus stimulation

4

defn of delerium

disorientated, hallucinations, misperception of sensory stimuli; fluctuate between quiet/sleepy and alert/agitated

5

What is "abulia"? Damage to what area causes it?

awake but apathetic and no sponteneity

bilateral frontal lobe disease, lobotamized

6

What is "akinetic mutism"? Damage to what area causes it?

silent, altert looking but no mental activity with vigorous stimulation

frontal lobes and hypothalamus

7

Difference between minimally conscious states and vegetative state?

MCS = fragements of awareness

vegetative = awake, no awareness or meaningful interaction with the environment

8

can reach for objects, grunt or gesture in response to a command, visually fixate and track but are unable to do much more

minimally conscious state

9

What are the 2 components of consiousness

arousal = ascending tracts
content = cortical circuits (awareness and cognition)

10

lesions in what areas are known to cause coma

extensive bi-hemispheric disease
diencephalon (thalamus and hypothalamus)
peri-aqueductal gray
upper 1/3 of ponitine tegmentum

11

areas that produce coma when damaged are called

ascending arousal system

12

Describe the parts of the ascending arousal system and what they do

2 cholinergic nuclei that inhibit thalamic neurons that synchronizes with cortex to induce sleep

monoaminergic nuclei that improve signal to noise ration and avoid misperception of incoming stimuli

13

sleep promoting center of the brain. how does it work?

VLPO--sends GABA and galanin (inhib neuropeptide) to the many nuclear centers that promote wakefulness

14

ascending arousal system receives feedback from what sources

thalamus, limbic system, fronto-parietal assc cortex

...these areas mediate emotional memories and permit concentrated attention to one sensory modality when necessary...

15

loss of feedback to ascending arousal system leads to...

abulia or akinetic mutism = apathy and indifference to sensory stimuli
...i.e. cannot be aroused?....

16

What parts of the brain herniate in a transtentorial heriation

temporal lobe or uncus (of temporal lobe)

17

complications of uncal herniation

1. compression of occulomotor nerve (mydriasis + eye down and out)
2. compress midbrain --> Duret's hemorrages
3. PCA compression --> ipsilateral stroke in occipital lobe

18

what is a bilateral uncal herniation called?

central herniation

19

herniation that pushes brain under the falx cerebri

falcrine herniation (herniation of cingulate gyrus)

20

complication of falcrine herniation

ACA compression (/stroke)

21

cause of lethargy in central herniations

compression of reticular grey in thalami

22

cause of small reactive pupils in central herniation

compression of hypothalamus

23

if central herniation is not corrected, the pupils will go from being small to... why?

fixed in mid position bc para will get knocked out too when the herniation compresses the midbrain (Endinger-Westphal nucleus)

24

Late signs of central herniations

flexor then extensor posturing then cheyne-stokes respirations

25

what is the distinct syndrome caused by pontine hemorrhages

abrupt coma + pin point pupils + flaccid paralysis or flexor rigidity + horizontal gaze paralysis (eyes can only move vertically) + ocular bobbing (up and down)

26

What are patients that have pontine hemorrhages at risk for

locked in syndrome

27

in metabolic encephalopathy pupils are (reactive or inactive to light)

reactive
**in structural causes of coma they are inactive

28

3 most common causes of encephalopathy in the elderly

dehydration, infection, drug intoxication

29

presentation of metabolic encephalopathy

non-focal neuro exam defectis
negative CT
reactive pupils
myoclonis, asterixes, and tremor

30

what drugs are empriacally given to pateints in a coma

D50 THEN thamine, naloxone

**D50 BEFORE thiamine to prevent Wernicke's enchephalopathy

31

normal vital signs suggest what kind of coma

psychogenic

32

cheyne stokes respirations can be an early sign of

central and uncal herniations

33

decerebrate posturing =

extensor

34

flexor center is in ____ and extensor center is in _____

flexor = midbrian
extensor = pons

35

extensor posturing predominates when ___ is lost/damaged

midbrian / flexor center

36

decorticate posturing =

flexor

37

flexor or extensor posturing worse

extensor

38

poor prognosis if on day __ of coma, the ___ reflex is absent and absence of purposeful _____

day 3
no corneal reflex and no purposeful movements

39

aneurysm in ___ artery may also compress CN III

posterior communicating