Randomized cross-over trial comparing stress responses amongst undergraduates and surgeons with and without background music during simulated surgery

High stress may diminish a surgeon's performance in the operating room. Music is perceived to reduce stress in this setting, however the psycho-physiological effects of music on intra-operative stress in inexperienced and experienced operators is incompletely understood. The effect of music on the psychological (Six-Item State-Trait Anxiety Inventory STAI-6 and Surgical Taskload Index SURG-TLX) and physiological responses (e.g., heart rate variability) was determined to a simulated surgical task (carotid patch-angioplasty) in 15 medical students and 12 vascular surgeons under stressing conditions in a randomised crossover design. Music did not affect the speed or accuracy of the simulated surgical stress task performance. While the surgical task increased SURG-TLX scores from baseline to control (Δ32 22-42; mean difference 95% confidence interval) and to music (Δ30 20-40), and increased STAI-6 scores in both conditions, there was no difference between music and control. The surgical task also increased heart rate (peak Δ5.1 bpm 3.0-7.1 vs. baseline p < 0.0001) and an index of cardiac sympathetic nervous system activity, and reduced an index of parasympathetic nervous system activity, with the latter two exacerbated by music (SNS index: 0.14 0.004-0.27, p = 0.042; PNS index: - 0.11 - 0.22 to - 0.008, p = 0.032). The more experienced group performed faster and more accurately than the inexperienced group, but there were no psychological or physiological differences in their responses to music. Despite previous research identifying generally positive surgeon perceptions of music on the intra-operative experience of stress, herein, background music failed to improve surgical task performance or attenuate subjective ratings of task load and anxiety, and physiological arousal.