Heart rate variability as a measure of mental stress in surgery: a systematic review

Purpose There is increasing interest in the use of heart rate variability (HRV) as an objective measurement of mental stress in the surgical setting. To identify areas of improvement, the aim of our study was to review current use of HRV measurements in the surgical setting, evaluate the different methods used for the analysis of HRV, and to assess whether HRV is being measured correctly. Methods A systematic review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA). 17 studies regarding HRV as a measurement of mental stress in the surgical setting were included and analysed. Results 24% of the studies performed long-term measurements (24 h and longer) to assess the long-term effects of and recovery from mental stress. In 24% of the studies, artefact correction took place. Conclusions HRV showed to be a good objective assessment method of stress induced in the workplace environment: it was able to pinpoint stressors during operations, determine which operating techniques induced most stress for surgeons, and indicate differences in stress levels between performing and assisting surgery. For future research, this review recommends using singular guidelines to standardize research, and performing artefact correction. This will improve further evaluation of the long-term effects of mental stress and its recovery.