Pathophysiology of Acute Coma and Disorders of Consciousness: Considerations for Diagnosis and Management

Abstract

Disorders of consciousness are due to failure of the arousal system. In this review, the authors introduce the spectrum of disorders of consciousness and describe the structures, projections, and neurotransmitters involved in the generation and maintenance of arousal. Next, they discuss the neurologic diseases frequently associated with arousal failure. Evaluation of patients with disorders of arousal is summarized, including the neurologic exam, electrophysiological studies, biochemical testing, and imaging modalities. Finally, they review treatment options, including therapeutic hypothermia, medications, and deep brain and spinal cord stimulation.

Keywords

coma - consciousness - vegetative state - minimally conscious state - arousal - cardiac arrest - ischemic stroke - traumatic brain injury - therapeutic hypothermia - subarachnoid hemorrhage - intracranial hemorrhage

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