title: The Efficacy of Earplugs as a Sleep Hygiene Strategy for Reducing Delirium in the ICU: A Systematic Review and Meta-Analysis.
abstract: OBJECTIVE
  A systematic review and meta-analysis to assess the efficacy of earplugs as an ICU strategy for reducing delirium.
  
  
  METHODS
  MEDLINE, EMBASE, and the Cochrane Central Register of controlled trials were searched using the terms "intensive care," "critical care," "earplugs," "sleep," "sleep disorders," and "delirium."
  
  
  METHODS
  Intervention studies (randomized or nonrandomized) assessing the efficacy of earplugs as a sleep hygiene strategy in patients admitted to a critical care environment were included. Studies were excluded if they included only healthy volunteers, did not report any outcomes of interest, did not contain an intervention group of interest, were crossover studies, or were only published in abstract form.
  
  
  METHODS
  Nine studies published between 2009 and 2015, including 1,455 participants, fulfilled the eligibility criteria and were included in the systematic review. Studies included earplugs as an isolated intervention (n = 3), or as part of a bundle with eye shades (n = 2), or earplugs, eye shades, and additional sleep noise abatement strategies (n = 4). The risk of bias was high for all studies.
  
  
  RESULTS
  Five studies comprising 832 participants reported incident delirium. Earplug placement was associated with a relative risk of delirium of 0.59 (95% CI, 0.44-0.78) and no significant heterogeneity between the studies (I, 39%; p = 0.16). Hospital mortality was reported in four studies (n = 481) and was associated with a relative risk of 0.77 (95% CI, 0.54-1.11; I, 0%; p < 0.001). Compliance with the placement of earplugs was reported in six studies (n = 681). The mean per-patient noncompliance was 13.1% (95% CI, 7.8-25.4) of those assigned to receive earplugs.
  
  
  CONCLUSIONS
  Placement of earplugs in patients admitted to the ICU, either in isolation or as part of a bundle of sleep hygiene improvement, is associated with a significant reduction in risk of delirium. The potential effect of cointerventions and the optimal strategy for improving sleep hygiene and associated effect on patient-centered outcomes remains uncertain.
authors.affiliation: 1Department of Intensive Care Medicine, St John of God Hospital Subiaco, Subiaco, WA, Australia. 2School of Medicine and Pharmacology, University of Western Australia, Crawley, WA, Australia. 3Department of Intensive Care Medicine, Fiona Stanley Hospital, Murdoch, Perth, WA, Australia. 4Department of Intensive Care Medicine, Faculty of Health, University of Technology Sydney, Sydney, NSW, Australia. 5Department of Intensive Care Medicine, Royal Perth Hospital, Perth, WA, Australia. 6School of Medicine and Pharmacology, University of Western Australia, Crawley, WA, Australia.
authors.forename: Edward
authors.initials: E
authors.lastname: Litton
authors.forename: Vanessa
authors.initials: V
authors.lastname: Carnegie
authors.forename: Rosalind
authors.initials: R
authors.lastname: Elliott
authors.forename: Steve A R
authors.initials: SA
authors.lastname: Webb
mesh_terms: D002986:Clinical Trials as Topic; D003693:Delirium / Q000453:epidemiology / Q000517:prevention & control*; D020920:Dyssomnias / Q000453:epidemiology / Q000517:prevention & control*; D004430:Ear Protective Devices; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D010349:Patient Compliance; D012890:Sleep