Noise levels with the potential to impede communication during surgery

Surgical teams consist of personnel who may or may not regularly work together, among whom communication can be more difficult because of surgical masks, face shields, or goggles, factors believed to have contributed to a recent serious medication error that occurred when the anaesthetist misunderstood the surgeon’s request. In a multihospital, occupational health intervention study a sound level meter was used to measure ambient noise for 15 min or > during 256 surgeries included in the study. Results revealed an Leq of 70.7 dB(A) and peak of 115.8 dB(A) (at the 95th percentile). Since the clarity of words depends on maintaining a signal-to-noise ratio of at least 15 dB(A), personnel working with such noise would likely increase their speaking levels up to 75–85 dB(A), a level substantially higher than normal speech ranging from 55–65 dB(A). Although the effect of noise levels on patient safety, or the health of OR personnel who must raise their voices to be heard, as well as on the overall climate that results when noise is elevated, have not been thoroughly investigated, evidence of negative effects is growing. And, while further characterization of OR noise is justified, this should be carried out to develop tailored interventions that can then be evaluated. [Work was funded by Ontario’s Workplace Safety Insurance Board.]