Delirium Updated

Abstract

The new classification of organic mental disorders in Diagnostic and Statistical Manual of Mental Disorders. ed 3 (DSM-III)¹ features delirium as one of the seven organic brain syndromes. Acute failure of integrated cerebral functioning, due to a wide range of possible noxious factors, is manifested at the behavioral level by the syndrome of delirium.² Although well described by numerous writers since antiquity, delirium is still often misdiagnosed, and confusion about its essential features persists. For example, a recent report on lithium toxicity describes a patient as distractible, fully disoriented, and visually hallucinated, but curiously concludes that “despite the similarity of this illness to an acute delirium with occasional lucid intervals, the patient had no clouding of consciousness.”³ To counteract such diagnostic and related errors, an update of the diagnosis, pathogenesis, and management of delirium is presented, which supplements a previous extensive review.⁴