Efficacy of controlling night-time noise and activities to improve patients' sleep quality in a surgical intensive care unit

Aim: The aim of the study was to test the efficacy of sleep care guidelines for controlling night-time noise and improving sleep quality of patients in a surgical intensive care unit. Background: Poor sleep quality places critically ill patients at greater risk for infection, complications and mortality. Environmental stimuli such as noises, continuous lighting and frequent care-related activities in an intensive care unit interfere with patients' sleep. Design: The study used a quasi-experimental design. Method: Sixty surgical patients were recruited from an intensive care unit in Taiwan during December 2007-May 2008. The control group received the usual care, and the experimental group was cared for by nurses who followed the sleep care guidelines for noise and light reduction. Data were collected on noise level and sleep quality using the Sleep in the Intensive Care Unit Questionnaire, the Richards Campbell Sleep Questionnaire and a decibel meter. Results: The results showed that both the peak sound level (χ² = 50·1, p < 0·001) and average noise level (χ² = 46·5, p < 0·001) were reduced significantly, after implementing the guidelines. The perceived noise (t = -2·07, p = 0·046) and sleep interruptions from care-related activities (t = 5·282, p < 0·001) and noises (t = 4·361, p < 0·001) were all significantly lower in the experimental group than in the control group. The experimental group also reported better sleep quality (t = -2·28, p = 0·027) and sleep efficiency (t = -2·03, p = 0·047) than did the control group.Conclusions. These results support the efficacy of the guidelines for controlling night-time noise and care activities to improve patients' sleep quality. Relevance to clinical practice: Nurses should try to reduce external environmental stimuli and maintain an almost undisturbed period between midnight and 5:00 a.m. to enhance patients' sleep in a surgical intensive care unit.