A systematic review of the comparative effects of sound and music interventions for intensive care unit patients' outcomes.

Background: Despite syntheses of evidence showing efficacy of music intervention for improving psychological and physiological outcomes in critically ill patients, interventions that include nonmusic sounds have not been addressed in reviews of evidence. It is unclear if nonmusic sounds in the intensive care unit (ICU) can confer benefits similar to those of music.

Objective: The aim of this study was to summarise and contrast available evidence on the effect of music and nonmusic sound interventions for the physiological and psychological outcomes of ICU patients based on the results of randomised controlled trials.

Methods: This systematic review was directed by a protocol based on the Methodological Expectations of Cochrane Intervention Reviews. Quality of studies was assessed with the Cochrane risk of bias assessment tool. Searches were performed in the following databases: MEDLINE, Embase, APA PsycInfo, CINAHL Plus with Full Text, Academic Search Complete, RILM Abstracts of Music Literature, Web of Science, and Scopus.

Results: We identified 59 articles meeting the inclusion criteria, 37 involving music and 22 involving nonmusic sound interventions, with one study comparing music and sound. The identified studies were representative of a general ICU population, regardless of patients' ability to communicate. Our review demonstrated that both slow-tempo music and sound interventions can significantly (i) decrease pain; (ii) improve sleep; (iii) regulate cortisol levels; (iv) reduce sedative and analgesic need; and (v) reduce stress/anxiety and improve relaxation when compared with standard care and noise reduction. Moreover, compared to nonmusic sound interventions, there is more evidence that music interventions have an effect on stress biomarkers, vital signs, and haemodynamic measures.

Conclusion: These results raise the possibility that different auditory interventions may have varying degrees of effectiveness for specific patient outcomes in the ICU. More investigation is needed to clarify if nonmusic sound interventions may be equivalent or not to music interventions for the management of discrete symptoms in ICU patients.

Registration Of Reviews: The protocol was registered on Open Science Framework in November 6 2023 (https://doi.org/10.17605/OSF.IO/45F6E).