Effect of an Eye Mask-Based Blackout Protocol on Sleep Quality and Melatonin

Sleep disturbance is a common problem among patients hospitalized in intensive care units due to continuous light exposure, noise, and frequent medical interventions. Disruption of the normal day-night cycle may reduce melatonin secretion and negatively affect sleep quality and recovery. This randomized controlled study aimed to evaluate the effect of an eye mask-based blackout protocol on sleep quality and melatonin levels in patients hospitalized in a chest intensive care unit. Participants were randomly assigned to either an intervention group or a control group. Patients in the intervention group wore a lightproof eye mask during nighttime hours (11:00 p.m. to 05:00 a.m.) in addition to standard light-reduction practices, while the control group received routine intensive care. Sleep quality was assessed using validated subjective scales, and melatonin levels were evaluated by measuring urinary 6-sulfatoxymelatonin. The study sought to determine whether reducing nighttime light exposure using a simple, non-invasive intervention could improve sleep quality and support circadian rhythm regulation in intensive care patients.