Studies have used several methods, such as HRV analysis, salivary cortisol estimation, and questionnaire surveys, to assess surgeons’ stress and have reported an association with intraoperative environment, night work, patient factors, and surgeon factors.8,16,17 However, these previous methods are complicated, experimental, and not practical for checking stress in surgeons. In the present study, we used a commercially available wearable smart device for quantifying the level of surgeons’ stress in the operating theater. Using a novel, non-invasive and lightweight wrist-type wearable smart device was not only convenient and easy but also appropriate for the busy operational situations of surgeons; wearing and removing the wearable smart device and recording the results took less than five minutes.
One of the basic mechanisms for assessing stress in the wrist-worn wearable devices was the measure of HRV, which indicates the periodic variations in the HR and helps in the evaluation of the relative contributions of the sympathetic and parasympathetic nervous system. HRV has been proposed as a reliable biomarker of stress and health.18 Other studies have reported surgeons’ stress through assessing perioperative HRV.2,4,19
Our findings revealed that SpO2 decreased significantly before and after surgery compared with the resting state. Although the pulse oximetry transcutaneously monitors functional SpO2 of hemoglobin in arterial blood, SpO2 could be underestimated in the cold temperature of the operation room, which causes vasoconstriction of the peripheral blood vessels of surgeons.20 Additionally, the usage of surgical masks could have an effect of decreasing SpO2 in surgeons.21
When we designed this study, we hypothesized that surgeons’ stress would increase before and decrease after surgery. Our findings showed that stress significantly increased shortly before surgery compared with the baseline level. However, the stress level after surgery remained significantly higher; only the short-form STAI score significantly decreased after surgery. Thus, the surgeons were still under high physical stress even after surgery, whereas the psychological stress tended to be resolved after surgery.
In the present study, we found that the baseline stress was significantly higher in clinical fellows compared with surgical residents and professors. The work hours of surgical residents in South Korea have been capped at 80 hours/week, according to policy imposed in 2017. However, this limitation does not apply to clinical fellows, who continue to have extremely heavy workloads compared with other medical positions. Clinical fellows also play a pivotal role in perioperative care in most tertiary hospitals in South Korea. Thus, they are consistently exposed to stress related to inpatient management, including critical care. This could explain the highest stress level being reported among clinical fellows compared with their colleagues.
Meanwhile, the baseline stress level of professors was significantly lower compared with the other groups, but their postoperative stress level was significantly higher. Professors are responsible for surgeries as the main surgeon. Main surgeons are under environmental, physiological, and psychological pressure, as well as carry the responsibility for patients’ prognoses and the possibility of surgical complications. In the present study, the years of surgical experience, patient’s weight, and PAI were significantly associated with increments in the stress of surgeons. In general, obesity and PAI are usually associated with surgical difficulties and longer operation time, which could increase the surgeon’s stress.
The pre-operative period of emergency operations is especially more stressful for surgeons; their stress level is observed to decrease in the post-operation period.22 The uncertainty of emergency cases and resuscitation of critically ill patients could be important stress factors for surgeons. However, we found no significant difference between emergency and elective surgeries in terms of the stress level of surgeons. The participants’ pre-operative stress level was higher and their post-operative stress level lower in emergency operations, but not to a statistically significant degree. We also observed that night-time surgery did not increase the surgeon’s stress significantly compared with day-time surgery. However, considering that night duty could influence the efficiency of the surgeon for the next day’s duty, which could be associated with the patient’s safety, hospitals should consider giving surgeons the day off after night duty to prevent burnout among surgeons.
This study has several limitations. First, the wrist-worn wearable device could not be worn by surgeons during operations owing to contamination concerns. Therefore, we could not obtain data on the intraoperative changes in surgeons’ stress. Several chest-strap type monitors have been introduced, but these cause chest tightness and are uncomfortable for surgeons.23 Second, the categories of surgery were limited. Finally, we did not consider the experience and learning curves of residents and clinical fellows.
The use of smart devices in the health care industry is progressing in many areas. At present, many studies using wearable smart devices have been conducted on patients and workers in other fields, such as aviation, but rarely among medical professionals. The current work showed that surgeons’ stress significantly increased before and after surgery compared with their resting state, and clinical fellows’ stress was significantly higher compared with residents and professors. As far as we know, this is the first study to assess the stress level of surgeons, fellows and resident using commercially wearable smart device which gives subjective stress level. Our findings can be used to provide a better working environment for surgeons and help them preventing burnout.
In conclusion, we assessed surgeons’ stress using a wearable smart device and demonstrated that surgery significantly increased stress. A wearable smart device could be an intuitive and feasible method to estimate surgeon’s stress in the busy nature of the operating room.