Altered Mental Status in the Emergency Department

Abstract

Altered mental status is an umbrella term that covers a broad spectrum of disease processes that vary greatly in chronicity and severity. Causes can be a primary neurologic insult or a result of a systemic illness resulting in end-organ dysfunction of the brain. Acute changes in mental status are more likely than chronic changes to be immediately life-threatening and are therefore the focus of this review. Given the potential time-sensitive nature, acute changes in mental status must be addressed immediately and with urgency. We recommend a primary survey followed by a secondary survey with special attention to immediate life-threatening reversible causes. We then recommend a systems-based approach searching for any other life-threatening or reversible causes. Because the differential for altered mental status is broad, a comprehensive emergency department evaluation including a detailed history and physical exam as well as laboratory and radiographic testing is needed.

Keywords

altered mental status - confusion - altered behavior - generalized weakness - lethargy - agitation - psychosis - disorientation - inappropriate behavior - hallucination

Disclosures

J.H.H. is supported by the Veteran Affairs Geriatric Research, Education, and Clinical Center (GRECC). The content is solely the responsibility of the authors and does not necessarily represent the official views of Veterans Affairs.

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