Operating room noise levels in anaesthesia a systematic review and meta-analysis

Intraoperative noise is an occupational hazard with the potential to compromise anaesthetist performance and patient safety. The WHO recommends hospital sound exposure ≤ 35 dB LAeq (A-weighted equivalent continuous sound level), yet noise levels routinely exceed this level. This systematic review and meta-analysis aimed to determine intraoperative noise levels worldwide.

Five databases were searched from inception to May 2026, in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies were eligible for inclusion if they included surgical specialty and a measure of noise sampled recorded with validated sound metres. Studies were eligible for meta-analysis if they included a mean time-weighted average. Two authors undertook searches and risk-of-bias assessment. Meta-regression estimated pooled means, heterogeneity, and variance.

Fifty studies met the inclusion criteria in the systematic review, with 28 studies providing 43 unique datasets subclassified by type of surgical procedure for analysis. The pooled random-effects mean intraoperative noise level was 70.7 A-weighted dB [dB(A)] (95% CI 69.0-72.3). Subgroup analysis demonstrated the highest exposures in otolaryngology at 78.8 dB(A) (95% CI 72.8-84.7) and orthopaedics at 73.3 dB(A) (95% CI 68.9-77.8). Meta-regression confirmed surgical specialty as a significant predictor of mean exposure (Q=25.8, degrees of freedom=6, P=0.0002).

Anaesthetists are consistently exposed to intraoperative sound levels exceeding WHO guidelines, particularly in high-intensity specialties such as orthopaedics and otolaryngology. These findings provide a specialty-specific synthesis of noise exposure and highlight the need for targeted interventions, standardised measurement, and research linking exposure to clinical outcomes.