The physician should understand this involves an organized, sequential, prioritized approach.
Treatment of rapidly progressive, dangerous metabolic causes of coma (hypoglycemia)
Evaluation as to whether there is significant increased ICP or mass lesions.
Treatment of ICP to temporize until surgical intervention is possible.
The physician should understand and recognize:
Signs of supratentorial mass lesions
Signs of subtentorial mass lesions
The physician should be able to develop the differential diagnosis of metabolic coma.
An intact pontine reticular activating system
An intact cerebral hemisphere, or at least part of a hemisphere
Coma requires dysfunction of either the:
Pontine reticular activating system, or
Bihemispheric cerebral dysfunction
Supratentorial lesions cause coma by either widespread bilateral disease, increased intracranial pressure, or herniation.
Infratentorial lesions involve the RAS, usually with associated brainstem signs
Metabolic coma causes diffuse hemispheric involvement and depression of RAS, usually without focal findings
Rostral caudal progression of respiratory, motor, and pupillary findings
May not have other focal findings
Rostral caudal progression
CN III dysfunction and contralateral motor findings