Heart rate and heart rate variability as indirect markers of surgeons' intraoperative stress

In a difficult and demanding environment such as the operating room, the individual workload response of physicians is of particular importance. The aim of this study was to examine the specific effects of intraoperative stress on the cardiovascular system by measuring heart rate (HR) and heart rate variability (HRV).

In a cross-sectional study, the effect of intraoperative stress on autonomic balance, measured by HRV, among surgeons differing with respect to their intraoperative stress levels was studied. Based on their perceived stress (State Trait Anxiety Inventory), surgeons were classified into a stressed and a non-stressed sample. Data on HR and HRV were collected by means of ambulatory ECG-recordings. Changes in autonomic nervous system activity were quantified by frequency and time domain analysis of R-R interval variability. Demographic, anthropometric, and surgery-related group differences were assessed by non-parametric Mann-Whitney U test, differences between relative changes of HR and HRV by Wilcoxon signed-ranks test. In multivariate linear analysis of covariance, group differences were adjusted for possible confounding factors.

There was a significant difference in intraoperative HR for stressed and non-stressed surgeons (median: 99.3 vs. 63.7; P < 0.05). During sleep, HRV indices indicated a reduced autonomic recovery in stressed participants.

Our results reveal that higher perceived stress in the operating room is associated with increased intraoperative HR and decreased HRV at night. Non-stressed surgeons show greater relaxation during sleep compared to their stressed colleagues.