Effects of nonpharmacological delirium-prevention interventions on critically ill patients' clinical, psychological, and family outcomes: A systematic review and meta-analysis

Background: Delirium is common in critically ill patients and may lead to severe complications, such as falls and injuries. Nonpharmacological interventions have been widely suggested to prevent delirium, yet the effects remain uncertain.

Objectives: The aim of the study was to determine the effects of nonpharmacological interventions on preventing delirium and improving critically ill patients' clinical, psychological, and family outcomes.

Methods: Ten databases were searched from their inception to September 2020. Two reviewers assessed the methodological quality and extracted details of the included studies. The data were narratively or statistically pooled where appropriate. Dichotomous variables are presented as odds ratio (OR), and continuous variables are presented as mean difference (MD). The Grading of Recommendations Assessment, Development, and Evaluation criteria were used to assess the quality of evidence for each review outcome.

Results: Thirty-four studies (10 randomised controlled trials, eight controlled clinical trials, and 16 before-and-after studies) were included in the analysis. Low-certainty evidence indicated that nonpharmacological interventions reduced delirium incidence (OR = 0.43, 95% confidence interval [CI] [0.33, 0.55]), delirium duration (MD = -1.43 days, 95% CI [-1.94, 0.92]), and length of stay in the intensive care unit (MD = -1.24 days, 95% CI [-2.05, -0.43]). Moderate-certainty evidence demonstrated no effect on mortality. Narrative synthesis further implied improvements in patients' psychological recovery (two studies, very low-certainty evidence) and families' satisfaction with care (two studies, very low-certainty evidence) through nonpharmacological interventions. As for effective intervention types, moderate-certainty evidence demonstrates that early mobilisation (OR = 0.33, 95% CI [0.24, 0.46], five studies, 859 participants, I² = 24%), family participation (OR = 0.25, 95% CI [0.18, 0.34], four studies, 997 participants, I² = 21%), and use of multicomponent interventions (OR = 0.48, 95% CI [0.34, 0.69], 13 studies, 3172 participants, I² = 77%) are associated with reduced incidence of delirium.

Conclusions: Healthcare professionals are recommended to apply early mobilisation, family participation, or multicomponent interventions in clinical practice to prevent delirium. Further studies investigating the effects of nonpharmacological interventions on patients' psychological and family outcomes are warranted.