W7_04 Coma

Question 1

define coma

Answer 1

deep unresponsiveness where the patient cannot be aroused to respond to stimuli

Question 2

awareness results from what?

Answer 2

activity in the cerebral cortex

Question 3

arousal results from what?

Answer 3

activity of brainstem and diencephalic structures

Question 4

4 levels of arousal?

Answer 4

alert, obtunded, stupor, coma

Question 5

arousal and awareness in coma?

Answer 5

none in either

Question 6

arousal and awareness in vegetative state?

Answer 6

high arousal, but no awareness. can still laugh but unaware.

Question 7

arousal and awareness in minimally conscious state?

Answer 7

high arousal but little awareness

Question 8

arousal and awareness in locked in syndrome?

Answer 8

high in both.

Question 9

what structures must be affected to cause a coma?

Answer 9

both cerebral hemispheres or the ascending arousal system (paramedian region of upper brainstem or diencephalon)

Question 10

where is the lesion for locked in syndrome?

Answer 10

caudal pons (just below rostral pons, the area of arousal)

Question 11

name some causes of coma

Answer 11

compressive lesions;
destructive lesions;
diffuse intrinsic (e.g. epilepsy, infection);
metabolic brain disease;
psychiatric causes

Question 12

false localizing signs are produced at which anatomical location?

Answer 12

kernohan’s notch (left cerebral peduncle near the tentorial edge)

Question 13

uncal herniation can cause what?

Answer 13

hemiparesis (cerebral peduncle);
cortical blindness (PCA occlusion);
eye palsy (3rd nerve);
decreased arousal (brainstem)

Question 14

left paramedian pontine lesion causes what?

Answer 14

1.5 syndrome

Question 15

right lateral pontine lesion causes what?

Answer 15

gaze paralysis (can’t move towards side of lesion)

Question 16

MLF lesion causes what?

Answer 16

can’t adduct eyes for VOR

Question 17

describe the pupils in an E-W nucleus lesion

Answer 17

midposition, fixed

Question 18

describe the pupils in a pons sympathetic tract lesion

Answer 18

pinpoint

Question 19

how is kernig’s sign elicited and what is it for?

Answer 19

attempt for leg extension when hip flexed. for meningitis.

Question 20

brudzinski’s neck sign is for what?

Answer 20

meningitis. flex neck and see if legs and hips flex in response.