The behavioral effects of noise on man: the patient with "intensive care unit psychosis".

Alterations in the behavior of a critically ill patient, commonly referred to as ICU psychosis, may result from the physiological stresses incurred by these patients compounded by disruptions from environmental noises. Research has demonstrated that noise levels can greatly affect sleep stage progression as well as the frequency of awakenings in normal subjects during brief testing sessions. Furthermore, the ability to solve problems and tolerate frustration decreases when persons are exposed to noise. Clinical research studies have reported the excessive noise levels in everyday ICU equipment and procedures, such as hypothermia blankets, ventilators, and intermittent positive pressure breathing. Yet when patients were polled about the most disturbing noises, staff conversations and personnel activity were ranked among the highest. In addition, a direct relationship between level of noise and the amount of pain medication administered to patients was reported. Recommendations for the elimination of most noise within an ICU were personnel related. Being more cognizant of conversational topics and noise levels could greatly reduce the patient's level of irritability and feelings of impersonalization. Specific issues regarding current practice, staff behavior, and structural design were addressed. Thus familiarity with behavioral and clinical research regarding noise and its effect on man's behavior can serve as a guideline to the improvement of the quality of care that the critically ill patient receives.