Study On Sleep, Melatonin And Non-pharmacological Intervention For Sleep Promotion In ICU Patients

Part I Effects of a simulated ICU environment on nocturnal sleep, melatonin and cortisol in healthy subjectsObjective: To observe the noise and light condition in ICU environment and determine the physiological and psychological effects of ICU noise and light, and of earplugs and eye masks, used in these conditions in healthy subjects.Methods: ICUs noise and light were continuously monitored for 24 hours. Fourteen subjects underwent polysomnography under four conditions: adaptation, baseline, exposure to recorded ICU noise and light (NL), and NL plus use of earplugs and eye masks (NLEE). Urine was analyzed for melatonin and cortisol levels. Subjects rated their perceived sleep quality, anxiety levels and perception of environmental stimuli.Results: There were excessive noise levels in the ICUs,, with means 70.1dB(A) 24 hours and nighttime means > 60 dB(A). Nocturnal illumination in ICUs vary widely. Subjects had poorer perceived sleep quality, more light sleep, longer rapid eye movement (REM) latency, less REM sleep when exposed to simulated ICU noise and light (P<0.05). Nocturnal melatonin (P=0.007) and cortisol secretion levels (P=0.004) differed significantly by condition but anxiety levels did not (P=0.06). Use of earplugs and eye masks resulted in more REM time, shorter REM latency, less arousal (P<0.05) and elevated melatonin levels (P=0.002).Conclusions: There are excessive noise and night-time continuous artificial lighting in ICUs. Earplugs and eye masks promote sleep and hormone balance in healthy subjects exposed to simulated ICU noise and light, making their promotion in ICU patients reasonable. PartПNon-pharmacological interventions for sleep promotion in ICU patientsObjective To assess the efficacy of non-pharmacological interventions for sleep promotion in critically ill adult patients; To determine the effects of a noise and light reduction intervention combined relaxing music therapy on the sleep of adult patients in a cardiac surgery critical care unit.Methods First stage, Cochrane systematic review of randomized controlled trials (RCTs), quasi-RCTs and controlled clinical trials (CCTs) for non-pharmacological interventions for sleep promotion in ICU adult patients was performed. Clinical trials were searched in MEDLINE,EMBASE,CCTR,CBMdisc,PQDD,ISI web of science and from the reference of all include trials. The selection of studies, data extraction and assessment of quality were done independently by two reviewers. Data were processed by Rev Man 5.0 from the Cochrane collaboration. Second stage, a RCT to determine the effects of a noise and light reduction intervention combined relaxation music therapy on the sleep of adult patients in a cardiac surgery critical care unit was performed. Fifty patients were randomly assigned to intervention group (n=25) and the usual nursing care group (control group, n=25). Intervention group used earplugs and eye mask during nighttime sleep hours following a period of 15 to 30 minutes relaxing music. Urine from 8pm to 8am before surgery and first day, second day after surgery was analyzed for melatonin and cortisol levels. Partcipants rated their perceived sleep quality and perception of environmental stimuli.Results1. Fourteen trials including 965 patients met the inclusion criteria. Eleven trials were RCTs, 3 were CCTs. The quality of all trials varied, only one trial was grade A. One was about back massage and relaxation intervention, 3 were used earplugs and (or) eye masks, one was used relaxation and imagery, one was about ICU environment control, one was controlled periods for family member visit, one was used behavior intervention, one for nursing intervention before surgery, and 5 were about different ventilation mode. Meta-analysis indicated: use of earplugs and eye mask is not better than usual nursing care in term of subjective sleep quality, but two other trials showed use of earplugs and /or eye mask improved patients'subjective sleep quality. These interventions, such as back massage, ICU environment control, controlled periods for family member visit, nursing intervention before surgery improved patients subjective sleep quality effectively (P<0.05). There were significant increased fragmentation index and decreased percentage of stages 1 and 2 NREM sleep with pressure support ventilation (PSV) than with assist-control ventilation (ACV) (P<0.05). For no-sedated patients, there were no significant different in PSG sleep variables compared proportional assist ventilation (PAV) to pressure support ventilation (PSV) (P>0.05); For sedated patients, the sleep efficiency was significantly higher with PAV than with high PSV (P<0.05).2. Five patients dropped out of the study, all in intervention group. No differences were found in nocturnal urinary secretion levels of 6-MT and cortisol of three nights between the intervention and control group (P>0.05). Differences in nocturnal urinary secretion levels of 6-MT and cortisol were both significant among the three nights within two group, the levels of 6-MT were significantly decreased on the first day and second day after surgery (P<0.05), but the levels of cortisol were increased significantly (P<0.05). Subjective sleep quality were significant increased compared intervention group with control group (P<0.05).Conclusion1. There was no sufficient evidence to conclude that non-pharmacological interventions is effective or safe in sleep promotion for adult ICU patients. More randomised controlled trials with greater number of participants are needed in future study.2. ICU patients after cardiac surgery suffer from severe decrease of nocturnal melatonin and increase of cortisol.3. A noise and light reduction intervention combined relaxing music therapy resulted in better subjective sleep quality.4. A noise and light reduction intervention combined relaxing music therapy...