MANIFESTATIONS OF BRAIN LESIONS (CONSCIOUSNESS)

CONSCIOUSNESS

awareness of external/internal world

disorders of consciousness can affect:

1. level of consciousness

2. content of consciousness

level of consciousness

characterized by impaired arousal or wakefulness; result from acute lesions of RAS and both cerebral hemispheres

1. drowsiness

2. delirium

3. stupor

4. coma

enumerate the 4 levels of consciousness

1. dementia

2. amnestic disorders

enumerate the 2 content of consciousness

Drowsiness

• ready arousal

• able to respond verbally and fonding off movements induced by painful stimuli

Acute Confusional State (Delirium)

• px responds to at least some stimuli in a purposeful manner but sleepy, disoriented, inattentive

• agitation predominates/alternates drowsiness + autonomic changes, hallucinations

• increased circulating catecholamines → intoxiaton with stimulant drugs (amphetamines)

• high fever

• withdrawal from sedatives

causes of delirium

Stupor

• can be aroused only with vigorous and repeated stimuli

• absent, slow, inadequate response to spoken demands

• restless, stereotyped motor activity

• reduction in natural shifting of positions

Coma

• most severe degree of depressed consciousness

• unresponsive + unarousable

• appears to be asleep

1. Deep coma

2. semi coma/light coma

2 types of coma

Sleep

• share features with coma

• px can be aroused to normal consciousness

content of consciousness

• isolated disorder of language and memory due to focal brain lesions

• dementia = widespread detoriation of mental functions

Glasgow Coma Scale

• can be obtained by sum of score for each response

• GCS less than 7 = poor prognosis