370 Evaluating Noise and Light in Critical Care and Their Impact on Patients’ Sleep: A Closed-Loop Audit

Abstract Aim Sleep quality is often impaired in hospitalised patients, particularly in critical care, and is associated with worse outcomes such as increased delirium. Environmental factors, including excessive noise and bright lighting at night, contribute significantly to sleep disruption. This audit evaluated compliance with local guidelines on noise and light control and their impact on patients’ sleep. Method Compliance with the trust guideline ‘lights out and radios off by 10 pm’ was assessed in the Intensive Therapy Unit (ITU) and High Dependency Unit (HDU). Night-time noise levels were recorded at 4-hourly intervals. Patient-reported sleep quality was assessed using the Richards-Campbell Sleep Questionnaire (RCSQ). A second cycle was then conducted to evaluate the effectiveness of interventions such as raising awareness of critical care staffs, offering eye masks and ear plugs to patients, and clustering nursing intervention and care overnight. Results Compliance improved in both ITU (lights: 20% to 30%; radio: 70% to 70%) and HDU (lights: 56% to 70%; radio: 56% to 80%). Average night-time noise levels fell from 46 dB to 40 dB. Reported sleep duration increased in ITU (5.1 to 5.3 hours) and HDU (4.0 to 5.5 hours). RCSQ scores improved in both units (ITU: 53.5 to 56.4; HDU: 34.8 to 60.2). Fewer patients reported being disturbed by noise and monitor alarms (ITU: 33% to 25%; HDU: 80% to 30%). Conclusions Targeted environmental changes improved both compliance with sleep-promoting guidelines and patient-reported sleep quality. Ongoing education and interventions are recommended to sustain improvement and optimise sleep conditions in critical care.