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The striking state in which a patient with previously intact mentality becomes confused is observed daily on the medical, surgical, and emergency wards of a general hospital. Occurring, as it often does, during an infection with fever or in the course of a toxic or metabolic disorder (such as renal or hepatic failure) or as an effect of medication, drugs, or alcohol, it never fails to create problems for the physician, nurses, and family. The physician has to cope with the problem of diagnosis, often without the advantage of a lucid history, and any program of therapy is constantly impeded by the patient’s inattention, agitation, sleeplessness, and inability to cooperate. Nurses are burdened with the need to provide satisfactory care and a safe environment for the patient, and at the same time, maintain a tranquil atmosphere for other patients. The family must be supported as it faces the frightening prospect of a deranged mind with peculiar behaviors and all it signifies.
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These difficulties are magnified when the patient arrives in the emergency ward, having behaved in some irrational way, and the clinical analysis must begin without knowledge of the patient’s background and underlying medical illnesses. It is our view that such patients should be admitted to a general medical or neurologic ward. Transfer of the patient to a psychiatric service is undertaken only if the behavioral disorder proves impossible to manage on a general hospital service.
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The definition of normal and abnormal states of mind is difficult because the terms used to describe them have been given so many different meanings in both medical and nonmedical writings. Compounding the difficulty is the fact that the pathophysiology of the confusional states and delirium is not fully understood, and the definitions depend to some extent on their clinical causes and relationships. The following nomenclature has proved useful and is employed in this and subsequent chapters.
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Confusion is a general term denoting the patient’s incapacity to think with customary speed, clarity, and coherence. Its most conspicuous attributes are impaired attention denoting reduced power of concentration, accompanied usually by disorientation—which may be manifest or is demonstrated only by direct questioning—inability to properly register immediate events and to recall them later, a reduction in the amount and quality of all mental activity, including the normally constant inner ideation and sometimes, by the appearance of bewilderment. Thinking, speech, and the performance of goal-directed actions are less affected but are nevertheless impersistent or abruptly arrested by the intrusion of the slightest external stimulus. Reduced perceptiveness and accompanying visual and auditory illusions or hallucinations are variable features that may be appended to the picture. This is what may be termed the global confusional state.
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These disturbances appear in many contexts. The medical and psychiatric literature has adopted the term delirium to describe all confusional states (discussed further on). ...