300 Coma

Question 1

Defined as deep sleeplike state with eyes closed from which patient cannot be aroused

Answer 1

coma

Question 2

refers to a higher degree of arousability in which the patient can be transiently awakened by vigorous stimuli accompanied by motor behaviour that leads to avoidance or withdrawal from uncomfortable or aggravating stimuli

Answer 2

stupor

Question 3

stimulates light sleep and is characterized by easy arousal and the persistence of alertness for brief periods

Answer 3

drowsy

Question 4

signifies a awake appearing but non responsive state often in a patient who has emerged from coma

Answer 4

vegetative state

Question 5

most common cause of the vegetative and minimally conscious states

Answer 5

cardiac arrest with cerebral hypoperfusion and head trauma

Question 6

refers to a partially or fully awake state in which the patient is able to form impressions and think as demonstrated by later recounting of events but remains virtually immobile and mute

Answer 6

akinetic mutism

Question 7

akinetic mutism results from damage of what

Answer 7

the condition results from damage in the regions of the medial thalamic nucle or the frontal lobes, or from extreme hydrocephalus

Question 8

describes a milder form of akinetic mutism characterized by mental and physical slowness and diminished ability to initiate activity

Answer 8

abulia

Question 9

what part of the brain is damaged when patient presents with abulia

Answer 9

medial frontal lobes and their connections

Question 10

hypomobile and mute syndrome that occurs usually as part of major psychosis typically schizoprenia or major depression

Answer 10

catatonia

Question 11

How is catatonia different from akinetic mutism

Answer 11

Catatonia and akinetic mutism are superficially similar but in catatonia clinical evidence of cerebral damage such as hyperreflexia and hypertonicity of the limbs is lacking

Question 12

describes an important type of pseudocoma in which an awake person has no means of producing speech or volitional limb movement but retains voluntary vertical eye movements and lid elevation thus allowing the patient to signal with a clear mind

Answer 12

locked in state

Question 13

what part of the brain is damaged in patients with locked-in state

Answer 13

usual cause is infarction of the basilar artery, hemorrhage of the ventral pons that transects all descendint motor (corticospinal or corticobulbar) pathways

Question 14

Damage to what systems leads to coma

Answer 14

widespread damage to the cerebral hemisphere or reduced activity of the reticular activating system (RAS) which is diffusely located in the brainstem

Question 15

separates the right and left cerebral hemispheres

Answer 15

falx

Question 16

separates the anterior and posterior fossae

Answer 16

tentorium

Question 17

refers to the displacement of brain tissue by an overlying or adjacent mass into a contiguous compartment that it normally does not occupy

Answer 17

herniation

Question 18

most common form of herniation

Answer 18

transtentorial herniation

Question 19

brain tissue is displaced from the supratentorial to the infratentorial compartment through the tentorial opening

Answer 19

transtentorial herniation

Question 20

refers specifically to the impaction of the anterior medial temporal gyrus (uncus) into the tentorial opening just anterior to and adjacent to the midbrain

Answer 20

uncal herniation

Question 21

first sign of uncal hernation

Answer 21

Enlargment of the ipsilateral pupil as the uncus compresses on the third nerved as the nerve transver the subarachnoid space

Question 22

refers to the hemiparesis contralateral to the hemiparesis and Babinski sign that result the displacement of the cerebral penduncle

Answer 22

Kernohan_ Woltman sign

Question 23

denotes symmetric downward movement of the thalamic structures through the tentorial opening with compression of the upper midbrain

Answer 23

central transtentorial herniation

Question 24

heralding signs of central transtentorial herniation

Answer 24

miotic pupils and drowsiness

Question 25

displacement of the cingulate gyrus under the falx and across the midline

Answer 25

transfascial herniation

Question 26

downward forcing of the cerebellar tonsils into the foramen magnum

Answer 26

foraminal herniation

Question 27

why is forminal herniation deadly

Answer 27

it causes early compression of the medulla leading to respiratory arrest

Question 28

How much horizontal displacement of the pineal gland is associated with drowsiness

Answer 28

3-5 mm displacement

Question 29

How much horizontal displacement of the pineal gland is associated with stupor

Answer 29

6-8 mm displacement

Question 30

how much horizontal displacement of the pineal gland is associated with coma

Answer 30

more than 9 mm displacement

Question 31

True or false. Unlike hypoxia- ischemia which causes neuronal destruction, most metabolic disorders such as hypoglycemia, hyponatremia cause only minor neuropathologic changes.

Answer 31

True.

Question 32

True or false. Coma and seizures are common accompaniments of large shifts in sodium and water balance in the brain.

Answer 32

True.

Question 33

When can temperature cause coma

Answer 33

hypothermia itself causes trauma when the temperature is less than 31 degrees Celsius

Question 34

May be the only sign of seizure in comatose patients

Answer 34

subtle, intermittent twitching movements of foot, finger, or facial muscle may be the only sign of seizure

Question 35

Sign of metabolic encephalopathy or drug intoxication in a drowsy and confused patient

Answer 35

bilateral asterixis

Question 36

What is decorticate posturing and what does it suggest?

Answer 36

Decorticate is flexion of the elbows and wrists and supination of the arms which suggests bilateral damage to the rostal to the midbrain

Question 37

what is decerebrate posturing and what does it indicate

Answer 37

Decerebrate posuturing is the extension of the elbows and wrists with pronation and indicates damage to the motor tracts caudal to the midbrain

Question 38

posturing in response to noxious stimuli indicates severe damage to what system?

Answer 38

Damaged cortisospinal system

Question 39

Abduction-avoidance movement of a limb denotes what?

Answer 39

intact corticospinal system

Question 40

True or false. Given that the nuclei of the cranial nerves and the RAS are both located in the brainstem, assessment of brainstem function is essential to localization of the lesion in coma

Answer 40

True.

Question 41

Most important brainstem reflexes

Answer 41

pupillary size and reaction to light; spontaneous and elicited eye movements, corneal responses and the respiratory system

Question 42

Pupillary sign that essentially exclude upper midbrain damage

Answer 42

reactive and round pupils of midsize 2.5-5 mm

Question 43

Most extreme pupillary signs

Answer 43

bilaterally dilated and unreactive pupils indicated severe midbrain damage from compression by a supratentorial mass

Question 44

Finding exonerates extensive damage in the midbrain and pons

Answer 44

spotaneous eye movements in coma in a form of conjugate horizontal roving

Question 45

How does seizure involving the frontal lobe look like

Answer 45

seizures involving the frontal lobe drive the eyes to the opposite side, simulating a pontine destructive lesion

Question 46

True or false. Eyes look toward a hemispheral lesion and away from a brainstem lesion.

Answer 46

True. Maxim

Question 47

Eyes may occassionally turn paradoxically away from the side of a deep hemispheral lesion. What do you can this phenomenon

Answer 47

wrong way eyes

Question 48

What is the eye position in thalamic and upper midbrain lesions

Answer 48

eyes turn downward and inward

Question 49

described as brisk downward and slow upwards movement of the eyes associated with loss of horizontal eye movements and where is the lesion

Answer 49

ocular bobbing; diagnostic of bilateral pontine damage

Question 50

described as slower arrythmic downward movement followed by faster upward movement? Where is the lesion

Answer 50

ocular dipping; indicates diffuse cortical anoxic damage

Question 51

True or false. Doll's eye is normally suppressed in awake patients

Answer 51

True. It is suppressed in awake person and intact frontal lobe

Question 52

What does a positive dolls eye mean?

Answer 52

reflects both reduced cortical influence on the brainstem and intact brainstem pathways

Question 53

provides more intense stimulus for the oculocephalic relfex but provides essentially the same information

Answer 53

thermal or caloric stimulation of the vertibular apparatus

Question 54

what it the normal result to caloric stimulation

Answer 54

tonic deviation of both eyes to the cold water irrigation

Question 55

what is the caloric stimulation response in comatose patient?

Answer 55

nystagmus in the opposite direction of the cold water irrigation

Question 56

what is the normal corneal reflex

Answer 56

brief bilateral lid closure when cornea is touched with wisp of cotton

Question 57

what does the corneal reflex mean

Answer 57

corneal reflex depend on the integrity of pontine pathways between the fifth (afferent) and seventh (efferent) cranial nerves

Question 58

True or false, respiratory patterns are less of localizing value in comparison to other brainstem signs

Answer 58

True.

Question 59

Respiratory pattern. Typically cyclic form , ending with brief apneic period. What does this signify?

Answer 59

Cheyne Stokes respirations signifies bihemispheric damage or metabolic suppression with pontomesencephalic lesions

Question 60

Respiratory pattern. Rapid deep breathing. What does this signify?

Answer 60

Kussmaul breathing. Implies metabolic acidosis but may also occur with pontomesencephalic lesions

Question 61

Agonal grasps are due to what

Answer 61

lower brainstem (medullary damage) and recognized as terminal respiratory pattern of severe brain damage

Question 62

EEG finding. Widespread fast beta activity

Answer 62

coma from sedative drugs

Question 63

EEG finding. Predominant high voltage slowing (triphasic waves) the frontal region

Answer 63

metabolic encephalopathy

Question 64

What is alpha coma

Answer 64

widespread variale 8 to 12- hz activity resembling normal alpha rhythm of waking but it is not altered by environmental stimuli

Question 65

when do you see alpha coma

Answer 65

alpha coma results from pontine or diffuse cortical damage and is associated with poor prognosis

Question 66

EEG finding. Normal alpha activity suppressed by stimulating the patient.

Answer 66

locked in syndrome, hysteria or catatonia

Question 67

3 broad categories of coma

Answer 67

coma without focal neurologic signs as in metabolic and toxic encephaties; coma with prominent focal signs as in stroke and cerebral hemorrhage; meningitis syndrome characterized by fever or stiff neck

Question 68

cerebrovascular disease that can lead to coma

Answer 68

basal ganglia and thalamic hemorrahge (acute but no instantaneous), pontine hemorrhage (sudden onset); cerebellar hemorrhage; basilar artery thrombosis, subarachnoid hemorrhage

Question 69

True or false. Infarction in the MCA territory leads to instantenous coma.

Answer 69

False. But large infractions causing edema can have mass effect leading to coma

Question 70

True or false. Children and young adults may have ominous early clinical findings such as brainstem reflexes and yet recover so ultra early prognistication is unwise.

Answer 70

True.

Question 71

How is the observation prior to declaring a patient is brain dead

Answer 71

observation of 6-24 hour is recommended

Question 72

refers to ta state of irreversible cessation of all cerebral and brainstem function with preservation of cardiac activity and maintenance of respiratory and somatic function by artificial means

Answer 72

brain death

Question 73

is the only type of damage recognized as morally, ethically and legally equivalent to death

Answer 73

brain death