Loudness in the Operating Room during Cardiac Surgery: Are Our Operating Rooms Quiet Enough?

Objectives: Technical devices and actions in the operating room (OR) result in higher noise levels. Increasing noise in the OR may increase the risk of errors, while complex and sophisticated surgical procedures need a quiet and harmonic environment. Therefore, we asked, how loud is it actually in a cardiac surgery OR?

Methods: During cardiac surgery with cardiopulmonary bypass (CPB), loudness levels were measured in three different places in the OR and at different situations: (1) next to operating table, (2) in the vicinity of the heart–lung–machine (HLM), and (3) at the IT work place. The 1-second loudness peaks dB(A) were recorded with calibrated loudness meters (sound-level meter Voltcraft DL-161S and sound-level calibrator SLC-100, CE, Hirschau, Germany) and measurements were done at 1-meter distance from noise source and from ear level. Additionally, maximum levels of typical acoustic events (sound level meter: SL–451, CE, Hirschau, Germany) were recorded and frequency spectrum analysis (FFT plot, ONYX) was performed. For comparison, measurements were performed on high traffic roads (highway A7 and federal road B3).

Results: The highest loudness in OR was registered near the operating table with median level of 62.7 dB(A) (range: 47.8–113.1 dB(A); p < 0.01 vs. HLM and IT work place). Uncontrolled conversation increased loudness to 72 dB(A), work of hypothermia device to 78 dB(A), cardiotomy suction to 160 dB(A), and unpacking of sterile materials up to 115 dB(A). Comparing loudness in the OR with loudness on high traffic roads (median: 60.7 dB(A), range: 32.9–96.6), levels were comparable to the loudness of highway.

Conclusion: Present study reveals status quo of loudness in OR during cardiac surgery. The measured loudness in the OR is in some moments comparable to the loudness of highways. We tolerate obviously suboptimal conditions for demanding operations at the highest level. For reducing the risk of errors and increase patient safety, noise reduction in the OR is mandatory.