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The striking event in which a patient with previously intact mentality becomes acutely confused is observed almost 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 grave problems for the physician, nursing personnel, 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 immediate 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 specter 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 non-medical 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, with all the imprecision that this entails. The following nomenclature has proved useful to us 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 and power of concentration, disorientation—which may be manifest or is demonstrated only by direct questioning—an inability to properly register immediate events and to recall them later, a reduction in the amount and a disruption in the 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 impersistent or abruptly arrested by the intrusion of irrelevant thoughts or distracted by the slightest external stimulus. Reduced perceptiveness and accompanying visual and auditory illusions or hallucinations and paranoid delusions (a psychosis) are variable features that may be appended to the picture.
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These psychologic disturbances may appear in many contexts. Confusion, as defined in this way, is an essential ingredient of the state called delirium (discussed further on), in which ...