Clinical Approach to Stupor and Coma (Hon)

Question 1

What generally causes coma?

Answer 1

Bilateral hemispheric dysfunction, brainstem dysfunction or both

Question 2

What are the requirements of consciousness?

Answer 2

1) Arousal

2) Awareness

Question 3

Consciousness depends on arousal of cerebral cortex by?

Answer 3

The brainstem ascending reticular activating system

Question 4

Coma and stupor are caused by?

Answer 4

1) Diffuse or bilateral impairment of both cerebral hemispheres
2) Failure of brainstem ARAS
3) Both the above

Question 5

What are broad categories of lesions that produce coma?

Answer 5

1) Large, pressure producing Supratentorial mass lesions that involve ARAS
2) Infratentorial mass lesions that involve the brainstem
3) Diffuse or multifocal brain disease

Question 6

What are broad categories of lesions that produce coma?

Answer 6

1) Large, pressure producing Supratentorial mass lesions
2) Infratentorial mass lesions that involve the brainstem
3) Diffuse or multifocal brain disease

Question 7

What are some examples of supratentorial causes of stupor and coma that affect the unilateral hemisphere (mass effect)?

Answer 7

1) Intracerebral hemorrhage
2) Large MCA infarct
3) Subdural hematoma
4) Epidural hematoma

Question 8

What are some examples of supratentorial causes of stupor and coma that affect bilateral hemisphere?

Answer 8

1) Subarachnoid hemorrhage
2) Cerebral edema
3) Acute hydrocephalus

Question 9

What are some examples of subtentorial causes of stupor and coma?

Answer 9

1) Pontine hemorrhage
2) Basilar artery occlusion
3) Central pontine myelinolysis

Question 10

What causes the pupil to be enlarged on one side?

Answer 10

Parasympathetic dysfunction (usually CN III)

Question 11

What causes pinpoint pupils?

Answer 11

1) Pontine lesions
2) Opiates
3) Pilocarpine

Question 12

What extraocular movement is common to see in comatose patients?

Answer 12

Roving eye movements

Question 13

If the roving eye movements are moving together (conjugate) this implies?

If they are dysconjugate this implies?

Answer 13

1) Brainstem intact

2) Brainstem lesion

Question 14

Which direction do the eyes move with a destructive hemispheric lesion?

With an irritative hemispheric lesion?

With a destructive brainstem lesion?

Answer 14

1) Toward lesion
2) Away from lesion
3) Away from lesion

Question 15

Oculocephalic maneuver (Doll’s Eyes) is used to assess which CNs?

Answer 15

III, IV, and VI

Question 16

When performing the Oculocephalic maneuver, what direction do the eyes move with passive horizontal head rotation?

what direction do the eyes move with passive vertical head rotation?

Answer 16

1) Horizontally opposite

2) Vertically opposite

Question 17

When performing a caloric (oculovestibular) reflex what to you first want to make sure of?

Answer 17

Canal is clear and TM intact

Question 18

Unilateral cold water irrigation with intact brainstem causes the eyes to deviate to which side?

Bilateral irrigation?

Answer 18

1) Toward irrigated side

2) Downward

Question 19

A patient in the decorticate position (arms flexed, legs extended) points to the issue located where?

If they are in the decerebrate position (all extremities extended)?

Answer 19

1) Hemispheric

2) Brainstem

Question 20

The initial signs of supratentorial mass lesions are usually?

The progression of signs are?

Motor signs are often?

Answer 20

1) Focal
2) Rostral to caudal
3) Asymmetric

Question 21

Herniation Syndromes are caused by?

Answer 21

Expanding supratentorial mass lesions

Question 22

The effect of herniation syndrome is to?

Answer 22

Displace brain tissue into adjacent intracranial compartments

Question 23

Uncal transtentorial herniations causes what do be compressed?

What does this cause initially?

What progressive sign is seen next?

Answer 23

1) CN III
2) Ipsilateral dilated pupil
3) Ipsilateral hemiparesis

Question 24

What are usually present with subtentorial mass lesions?

Answer 24

Cranial nerve palsies

Question 25

With diffuse/metabolic causes coma, what usually precedes motor signs?

Motor signs are usually?

Answer 25

1) Confusion and stupor

2) Symmetrical

Question 26

What are some general causes of diffuse/metabolic coma?

Answer 26

1) Hepatic/renal failure
2) Hyper/hypoglycemia
3) Hyper/hyponatremia
4) Endocrine disorders

Question 27

What occurs whenever blood flow is inadequate to meet the metabolic requirements of the brain, as in cardiac or pulmonary arrest?

Answer 27

Global Cerebral Ischemia

Question 28

Global Cerebral Ischemia usually lasts for how long?

Answer 28

≤ about 6 minutes

Question 29

What is brain death by definition?

Answer 29

1) Irreversibility
2) Complete cessation of brain function
3) Persistence

Question 30

In order to determine cessation of all brain function, what is the gold standard to confirm this?

(She emphasized this)

Answer 30

Apnea test

Question 31

What is the apnea test?

She emphasized this

Answer 31

Respiratory responses are absent at 8 to 10 minutes

after the patient’s pC02 is allowed to rise to 60mmHg, while oxygenation is maintained with 100% O2

Question 32

If a comatose patient is febrile and a source cannot be determined and the CT is normal, what should be the next step?

(She emphasized this)

Answer 32

Lumbar puncture