This disturbance in activity level, coupled with an altered level of consciousness, should heighten the concern that an acute confusional state exists, but the hypoactive, quiet, withdrawn individual who is frightened by the surroundings and tries to shut them out may not be noticed. In situations such as this, or if the patient is not a good historian, a family member may help provide ancillary evidence as to previous level of functioning. The nurses' notes also may provide valuable information. It is advisable to look for variations in behavior and awareness in the dark of evening as opposed to the light of day. Diagnosis Delirium should be diagnosed on clinical grounds and all efforts directed to determining its underlying cause.
Confusional states can accompany many medical and psychiatric conditions.
A clinical evaluation involves physical and laboratory examinations that focus on the possibility that a recognizable, underlying medical or surgical disorder exists. The individual's orientation and memory can become apparent in conversation but not in rapid rounds. Findings at this point may direct special attention to further neurological or cardiopulmonary evaluation. The basic laboratory evaluation should include a complete blood count with differential, a chest film, and an electrocardiogram. More specific tests such as a chemistry panel, toxicology screen, arterial blood gas, measurement of drug levels, or serological tests can be performed if the history and examination suggest them.