Measuring Mental Stress During Otologic Surgery Using Heart Rate Variability Analysis

Abstract

Objectives: Healthy individuals have significant beat-to-beat variability in heart rate, and this variability decreases with mental stress. We aim to use heart rate variability (HRV) to objectively compare mental stress levels in otologic surgeons at rest and during key portions of procedures. Design: Pilot study. Setting: Operating room and laboratory. Participants: Two neurotology fellows performed six mastoidectomy and facial nerve (FN) dissections in the operating room and six in a cadaver lab while continuous electrocardiograms were measured wirelessly. Five-minute samples were recorded during resting, preoperative, mastoidectomy, and FN dissection. Beat-to-beat time intervals were analyzed in time and frequency domains. The standard deviation of normal beat-to-beat intervals (SDNN) and the ratio of low frequency to high frequency power (LF/HF, measure of sympathetic tone) were calculated. Decreases in SDNN and increases in LF/HF indicate elevated mental stress. Results: Mean resting SDNN was 43.9 ± 9.2 ms, not statistically different from preoperative SDNN (34.1 ± 8.2 ms, p = 0.13). SDNN decreased during mastoidectomy (29.4 ± 11.7 ms) and FN dissection (22.8 ± 3.1 ms), which was significant compared to preoperative values (p = 0.03). Intraoperative LF/HF increased for FN dissection (6.8 ± 2.6) compared to resting (2.2 ± 0.7, p = 0.004), indicating increased sympathetic tone. Mastoid and FN cadaveric procedures resulted in SDNN of 33.6 ± 3.8 and 32.9 ± 4.7 ms, respectively, not statistically different from preoperative values (p = 0.82 and p = 0.94, respectively). Cadaveric FN dissection did not result in increased LF/HF (2.4 ± 0.9) compared to resting (p = 0.94). Conclusions: Decreased HRV and increased sympathetic tone were observed intraoperatively, indicating high levels of mental stress, particularly with FN dissection. Similar changes were not found during cadaveric dissections.

Heart rate variability as a strain indicator for psychological stress for emergency physicians during work and alert intervention: a systematic review

“…For example, reviews showed that stressed surgeons (e.g., intraoperatively) offered reduced HRV [ 16 , 17 ]. The same was observed for ENT physicians performing surgery [ 47 ]. High workload and low work control in non-operating resident physicians were also associated with of decreased heart rate variability [ 48 ].…”

<p>Perceived Surgeon Stress During No-Sedation Topical Phacoemulsification</p>

“…Two neuro-otology fellows were monitored with wireless continuous electrocardiograms while performing six mastoidectomies and facial nerve dissections both on patients and on cadavers. 16 Decreased heart rate variability and increased sympathetic tone -indicating high levels of mental stress -were observed during surgeries on patients, yet similar changes did not occur during cadaveric dissections. Practice-related stress may lead to physician burnout, family problems, decreased quality of patient care, depression, and professional impairment because of illicit drug or alcohol abuse.…”

“…[1][2][3][4][5][6] Low levels of stress may improve surgical performance but higher levels can adversely affect cognitive function and systemic health. [7][8][9][10][11][12][13][14][15][16][17][18] Unfortunately, few studies regarding stress among ophthalmic surgeons have been published in the literature. [19][20][21][22] The present study aims to improve our understanding of surgeon-related stress that occurs during phacoemulsification.…”

Methods and Measures for Mental Stress Assessment in Surgery: A Systematic Review of 20 Years of Literature

“…Generally, an increase in average HR indicates elevated sympathetic activity and physical expenditure, and decrease in HRV corresponds to smaller changes in time interval between consecutive heart beats, more arousal and strain, and less cardiac relaxation [4]. HRV is controlled by the autonomic nervous system [125] and is calculated through temporal features (SDNN, RMSSD, pNN50) and spectral features (LF: sympathetic activity, HF: parasympathetic activity, LF/HF) [133]. An increase in LF/HF shows imbalance in the autotonomic tone and increase in mental stress [125].…”

“…HRV is controlled by the autonomic nervous system [125] and is calculated through temporal features (SDNN, RMSSD, pNN50) and spectral features (LF: sympathetic activity, HF: parasympathetic activity, LF/HF) [133]. An increase in LF/HF shows imbalance in the autotonomic tone and increase in mental stress [125]. The majority of reviewed studies computed or read measured heart rates, followed by spectral and temporal feature analysis for HRV.…”