RESUMEN
Excessive noise is ubiquitous in the ICU, and there is growing evidence of the negative impact on work performance of caregivers. This study aims to determine the effectiveness of interventions to reduce noise in the ICU. DATA SOURCES: Databases of PubMed, EMBASE, PsychINFO, CINAHL, and Web of Science were systematically searched from inception to September 14, 2022. STUDY SELECTION: Two independent reviewers assessed titles and abstracts against study eligibility criteria. Noise mitigating ICU studies were included when having at least one quantitative acoustic outcome measure expressed in A-weighted sound pressure level with an experimental, quasi-experimental, or observational design. Discrepancies were resolved by consensus, and a third independent reviewer adjudicated as necessary. DATA EXTRACTION: After title, abstract, and full-text selection, two reviewers independently assessed the quality of each study using the Cochrane's Risk Of Bias In Nonrandomized Studies of Interventions tool. Data were synthesized according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, and interventions were summarized. DATA SYNTHESIS: After screening 12,652 articles, 25 articles were included, comprising either a mixed group of healthcare professionals (n = 17) or only nurses (n = 8) from adult or PICU settings. Overall, the methodological quality of the studies was low. Noise reduction interventions were categorized into education (n = 4), warning devices (n = 3), multicomponent programs (n = 15), and architectural redesign (n = 3). Education, a noise warning device, and an architectural redesign significantly decreased the sound pressure levels. CONCLUSIONS: Staff education and visual alert systems seem promising interventions to reduce noise with a short-term effect. The evidence of the studied multicomponent intervention studies, which may lead to the best results, is still low. Therefore, high-quality studies with a low risk of bias and a long-term follow-up are warranted. Embedding noise shielding within the ICU-redesign is supportive to reduce sound pressure levels.
RESUMEN
OBJECTIVES: To explore sound levels, alarm frequencies and the association between alarms and sound levels. DESIGN: A single center observational cross-sectional study. SETTING: Four intensive care units. MAIN OUTCOME MEASURES: Contribution of alarms: red (life threatening), yellow (indicate excess of limits) and blue (technical) to sound pressure levels dB(A) at nursing stations. RESULTS: Mean sound pressure levels differed significantly between day (56.1 ± 5.5), evening (55.1 ± 5.7) and night periods 53.6 ± 5.6; p < 0.01. 175,996 alarms were recorded of which 149,764 (85%) were yellow, 18,080 (10%) were red and 8,152 (5%) were blue. The mean sound levels without alarms (background) is 56.8 dB(A), with only red: 56.0 dB(A), only yellow: 55.6 dB(A), only blue: 56.0 dB(A) and mixed alarms: 56.3 dB(A). Yellow alarms (b = -0.93; 95% CI: -1.26 to -0.6; p < 0.001) were weakly but significantly associated with mean sound levels and lead to a slight decrease in noise level (1 dB), Red alarms (b = -0.3; 95% CI: -1.237 to 0.63; p = 0.52). The R Square of the model with all alarms was 0.01 (standard error of estimate, 6.9; p < 0.001). CONCLUSIONS: Sound levels were high during all day-periods. Alarms exceeding limits occurred most frequently. However, the contribution of alarms to sound levels measured at the nursing station is clinically limited.