Use of a non-invasive biomarker salivary alpha-amylase to assess the role of probiotics in sleep regulation and stress attenuation in surgical patients: A randomised double-blind clinical trial

Evaluating the effect of preoperative interventions on sleep health in the perioperative period: a systematic review

Surgery and general anaesthesia have deleterious effects on sleep and disrupted perioperative sleep health is a risk factor for poor surgical outcomes. The objective of this systematic review was to summarise preoperative interventions that report sleep outcomes. Studies that delivered an intervention initiated >24 h prior to surgery among an adult sample without a diagnosed sleep disorder were included. Studies were excluded if they were preclinical or were not published in English. MEDLINE, MEDLINE ePubs Ahead of Print and In-process Citations, Embase, Cochrane Central Register of Controlled Trials, APA PsycINFO, CINAHL, and the Web of Science were searched on February 2, 2023. This review was reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses and was registered with the International Prospective Register of Systematic Reviews (identifier: CRD42021260578). Risk of bias was assessed using the Cochrane Risk-of Bias 2 tool for randomised trials and the Risk Of Bias In Non-randomised Studies - of Interventions for non-randomised trials. Certainty of findings were assessed using the Grading of Recommendations, Assessment, Development and Evaluation framework. The searching yielded 10,938 total citations, and after screening resulted in 28 randomised and 19 non-randomised trials (47 total) with 4937 participants. Sleep was a primary outcome in 16 trials; a sleep outcome was significantly improved relative to comparator in 23 trials. This review demonstrates that preoperative sleep is modifiable via a variety of interventions, including pharmacological, non-pharmacological, and nursing interventions delivered preoperatively or perioperatively. Our results should be considered with caution due to an overall intermediate to high risk of bias in the included trials, and low to very low certainty of evidence. This review supports the modifiability of sleep health among surgical patients and provides the groundwork for preoperative sleep optimisation research.