Chapter 5. Clinical Approach to Stupor and Coma

Question 1

Questions 5-1:
Persistent vegetative state is often the sequel of coma when
patients have not improved to normal consciousness. Which of
the following features are expected in this state?
1. Preserved sleep-wake cycles
2. Eyes open in response to stimulation
3. Intact regulation of cardiac and respiratory function
4. Ability to respond commands only with eye blinks and
vertical eye movements
Select: A = 1, 2, 3. B = 1, 3. C = 2, 4. D = 4 only. E = All

Answer 1

Answer 5-1: A.
Patients in the persistent vegetative state have absence of cognitive function but retain sleepwake
cycles, regulation of cardiac and respiratory function, and will open eyes to stimulation. However, careful examination will reveal that the eye opening is an unpatterned response rather than a cognitive response. The ability to respond cognitively with only eye-blinks and vertical eye
movements is characteristic of the locked-in syndrome rather than persistent vegetative ‘. state. (p44)

Question 2

Questions 5-2 and 5-3:
The Glasgow coma scale is an important tool for assessment
of patients with decreased responsiveness. For the following
vignettes, indicate what is the correct score.
Question 5-2:
Patient appears awake but is confused. Obeys commands
briskly although the patient has to be re-directed to the task.
Eyes are open immediately on examination
A. 11
B. 12
C. 13
D. 14
E. 15

Answer 2

Answer 5-2: D.
The patient loses one point on verbal response
for the confused conversation (V4), however,
the patient receives full points for spontaneous
eye opening (E4) and obeying motor
conunands(M6).(P52)

Question 3

Question 5-3:
Patient is unresponsive to stimulation, does not open eyes or
orient to the examiner. No speech. All limbs have extensor
posturing in response to noxious stimulation.
A. 3
B. 4
C. 5
D. 6
E. 7

Answer 3

Answer 5-3: B.
The patient receives minimum points for verbal response (V I) and eye opening (E 1) since there is complete failure of these responses. However, the patient does receive an additional point for the tensor response to stimulation (M2). (P52)

Question 4

Questions 5-4 throngh 5-7:
The following disorders are in the differential diagnosis of
stupor and coma. For each of the clinical presentations, select
the most likely diagnosis.
A. Catatonia
B. Locked-in syndrome
C. Pseudocoma
D. Vegetative state
Question 5-4:
Patient is mute with markedly decreased motor activity. When
brought to a body posture,the position is maintained. Patient is
able to sit and stand.

Answer 4

Answer 5-4: A.
Catatonia is characterized by muteness and decreased motor activity. The persistence of postural abilities and the holding of a limb in a placed position is characteristic, and helps to
differentiate catatonia from cerebral processes. Note that some frontal lobe lesions can produce a presentation resembling catatonia. (P44)

Question 5

Question 5-5:
Patient is unresponsive with normal reflexes and tone. Diagnostic studies including MRl and EEG are normal.
A. Catatonia
B. Locked-in syndrome
C. Pseudocoma
D. Vegetative state

Answer 5

Answer 5-5: C.

Pseudocoma is most likely with unresponsiveness in the absence of abnormalities on exam or studies. (P44)

Question 6

Question 5-6:
Patient presents with failure to move any extremity to command, but is able to move eyes, particularly vertically on command.

A. Catatonia
B. Locked-in syndrome
C. Pseudocoma
D. Vegetative state

Answer 6

Answer 5-6: B.
Locked-in syndrome is usually due to pontine infarction and is characterized by quadriparesis and lower cranial nerve dysfunction. The patient may initially be felt to be comatose, though careful exam of eye movements shows that the patient is completely awake and responsive. (p44)

Question 7

Question 5-7:
Patient with a severe head injury has resolution of cerebral edema but is unresponsive to command and question. EEG shows preserved sleep-wake cycle.
A. Catatonia
B. Locked-in syndrome
C. Pseudocoma
D. Vegetative state

Answer 7

Answer 5-7: D.
The persistent vegetative state is characterized by unresponsiveness, though the eyes may open with stimulation. This is a sequel to coma where cardiac and respiratory regulationis preserved. Preservation of the sleep-wake cycle is typical, though the EEG will Dot show a normal waking background. (p44)

Question 8

Question 5-8:
All of the following are features of the locked in syndrome
except which one?
A. Inability to accept input from the environment
B. Ability to communicate using eye blinks and vertical eye
movements
C. Lesion in the ventral pons,bilaterally
D. Quadriplegia with lower cranial nerve palsies

Answer 8

Answer 5-8: A.
Patients with the locked-in syndrome have the
ability to accept input from the environment but marked deficit in ability to respond. hence the term, de-efferented state. All of the other features are typical of the locked-in syndrome. The most common cause is infarction of the pons bilaterally, often due to basilar artery thrombosis, although other causes exist. This is seldom a stable state, patients showing improvement or deterioration, although longterm survivors in this situation can exist (p44)

Question 9

Question 5-9:
Increased intracranial pressure with cerebral herniation affecting the brainstem is associated with which of the following features?
1. Decreased level of consciousness to the point of
unresponsiveness
2. Asymmetric third and/or sixth cranial nerve palsies
3. Increased blood pressure
4. Decreased heart rate
Select: A= 1.2.3. B = 1, 3. C =2, 4. D = 4 only. E = All

Answer 9

Answer 5-9: E.
All of these are typical findings with cerebral
herniation affecting the brainstem. Third and
sixth cranial nerve palsies can develop,
initially asymmetrically and ultimately
bilaterally. Incipient herniation should be
identified early because when the herniation
extends lower than the midbrain the damage is
usually irreversible. (P58-59)

Question 10

Questions 5-10 through 5-13:
Differentiating toxic-metabolic from structural causes of coma is a common important task in clinical diagnosis. For each of the following questions, select the clinical association.
A. Toxic-metabolic
B. Structural
C. Both
D. Neither

Question 5-10:
Small symmetric but reactive pupils.

Answer 10

Answer 5-10: A.
Metabolic and most toxic causes of coma can
produce small pupils with preserved
reactivity. A few toxic conditions can produce
dilated pupils, but the symmetry persists.
Cataract extraction and previous eye injuries
can affect the symmetry which would
otherwise be present. (pS9)

Question 11

Question 5-11:
Papilledema.

A. Toxic-metabolic
B. Structural
C. Both
D. Neither

Answer 11

Answer 5-11: B.
Structural causes are far more likely to cause
papilledema than metabolic and toxic causes. .
Papilledema can occur in lead intoxication and
hypoparathyroidism, both uncommon in
routine neurologic practice. (PS9)

Question 12

Question 5-12
Progressive decline in level of consciousness.
A. Toxic-metabolic
B. Structural
C. Both
D. Neither

Answer 12

Answer 5-12: c.
Both toxic and structural causes can be
associated with a progressive decline in
intellect then level of consciousness. (P59)

Question 13

Question 5-13:
Asymmetric muscle tone.
A. Toxic-metabolic
B. Structural
C. Both
D. Neither

Answer 13

Answer 5-13: B.
Struct:ur.allesioDS are likely to produce
asymmetric tone, with areas of increased tone suggesting corticospinal dysfunction. Metabolic and toxic conditions are more likely to produced Symmetric and usually decreased tone.(p60)

Question 14

Question 5-14:
All of the following statements regarding prognosis following
coma are true EXCEPT which?
A. Metabolic causes such as hepatic encephalopathy have
generally a worse prognosis than cerebrovascular causes of
coma
B. Prognosis is generally poor for non traumatic coma
C. Patients with traumatic coma may have satisfactory
improvement even following months of coma
D. Patients with nontraumatic coma who have not awoken
within one month arc unlikely to subsequently recover

Answer 14

Answer 5-14: A.
Metabolic causes of coma have generally a better prognosis than cerebrovascular causes including infarct and subarachnoid hemorrhage. The other statements are generally true. Patients with traumatic coma are younger and have a better prognosis than many non-traumatic causes. With trauma, recovery after prolonged coma can occur,
while this is distinctly unusual in patients with
non-traumatic coma. (p62-63)

Question 15

Question 5-15:
Brain death criteria mandate which of the following?
1. Patient in coma, showing no response to any modality of
stimulation
2. No spontaneous respirations even with careful apnea testing
3. Absence of brains tern reflexes
4. Absence of cerebral blood flow
Select: A = 1.2,3. B = 1,3. C = 2.4.0. 4 only. E = All

Answer 15

Answer 5-15: A.
Absent cerebral blood flow can be used as a
confirmatory test, but is not a mandatory
criterion for brain death. Depending on the
cause of the coma, period of observation
and/or other confirmatory tests may be
substituted for cerebral blood flow
determination. (P64)