The effect of an eye mask-based blackout protocol on patients' sleep quality and melatonin levels: a randomised...

Sleep disruption is among the most common problems in intensive care units due to continuous lighting, noise, and ongoing medical interventions. Disturbed circadian rhythms may decrease melatonin secretion and adversely affect patient recovery and well-being. Creating a dark environment during sleep may improve sleep quality and support melatonin regulation.

To evaluate the effect of an eye mask-based blackout protocol on sleep quality and melatonin levels in patients hospitalised in the chest intensive care unit.

This randomised controlled trial was conducted in the chest intensive care unit of a university hospital between August 2024 and May 2025. Sixty patients were randomly assigned to experimental (n = 30) and control (n = 30) groups. The experimental group received an eye mask-based blackout protocol (eye mask from 11:00 p.m. to 05:00 a.m. with a standardised nighttime light-reduction procedure), while the control group received routine care. Urine samples were collected overnight to measure melatonin metabolite (aMT6s) levels, and data were obtained using the Sleep Quality Visual Analogue Scale (VAS) and Richard Campbell Sleep Scale. Pre- and post-test values were compared and analysed using appropriate statistical tests.

Sleep quality scores and urinary aMT6s levels were significantly higher in the experimental group after the intervention (p < 0.001). The mean VAS score rose from 4.33 to 7.97, and the Richard Campbell Sleep Scale score increased from 224.67 to 447.50. Urinary aMT6s (ng/mg creatinine) increased from 15.06 to 97.09. No significant improvements in subjective sleep quality were observed in the control group, although urinary aMT6s levels also increased, suggesting that factors other than the intervention may have influenced aMT6s values.

An eye mask-based blackout protocol may improve sleep quality and may be associated with increased urinary aMT6s levels in intensive care patients.

Eye mask use is a simple, inexpensive, and non-invasive nursing intervention that may enhance patient comfort and improve subjective sleep quality in intensive care settings.

This clinical trial was registered at ClinicalTrials.gov with the identifier NCT07385768 (Record name/ID: ATAUNI-SLEEP-ICU-01). The record was initially released on 20 January 2026 and was last publicly released on 29 January 2026.