Prevalence of Surgical Flow Disruptions Across Intraoperative High- and Low-Workload Phases in Cardiac Surgery
Event Type
Oral Presentations
TimeTuesday, April 132:40pm - 3:00pm EDT
LocationPatient Safety Research and Initiatives
DescriptionSurgical flow disruptions (SFDs) are demonstrated to impact cognitive workload, as previously explored using retrospective, subjective self-report methods. Specifically, performance impairment in surgery was associated with increases in mental workload (Weigl et al., 2016). However, this relationship was only demonstrated in high-fidelity medical simulation, rather than real-life surgery. The goal of this descriptive study is to characterize cognitive and auditory SFDs during 5-minute segments of cardiac surgery procedures in the wild (operating room [OR]). Additionally, it aims to compare the nature of distractions observed during high team cognitive workload segments and low team cognitive workload segments for the OR team, measured using objective metrics.

Audio, video, and heart rate variability (HRV) data were collected intraoperatively from the attending surgeon, attending anesthesiologist, and primary perfusionist during cardiac surgery procedures at a tertiary teaching hospital (N=5). In this study, HRV served as an objective marker of cognitive workload. Procedures were divided into consecutive non-overlapping 5-minute segments. Segments were classified as high team workload segments if all three providers demonstrated above-average HRV levels, and were classified as low team workload segments if all three providers demonstrated below-average HRV levels. Within each segment, cognitive and auditory distractions were documented according to a modified version of the Disruptions in Surgery Index (see Jung et al., 2018). Cognitive distractions included a binary classification (Y=present/N=absent) of the following: teaching activity, device malfunction, irrelevant communication, management of another case, time pressure, and late arrival or absence of a surgical team member during the 5-minute segment observed. Auditory distractions included a count of the number of external communications, door openings, machine alarms, and loud noises per 5-minute segment observed.

Results revealed that higher team workload segments were associated with a higher percentage of cognitive distractions, namely irrelevant conversations (high workload: 20% (4/20) of segments; low workload: 13.33% (2/15) of segments) and management of another case (high workload: 15% (3/20) of segments; low workload: 6.67% (1/15) of segments). Chi-square tests of independence showed that the associations between workload and irrelevant conversations as well as workload and management of another case were not significant at the alpha level 0.05. Counts of auditory distractions such as external communications, machine alarms, and loud noises did not differ substantially between high- and low-workload segments. An independent, two-tailed t-test revealed that the count of door openings per segment, an auditory distraction, was significantly higher during low-workload segments (mean=3.4) compared to high-workload segments (mean=1.65, p=0.011). Overall, low-workload segments averaged 4.07 auditory distractions/segment, while high-workload segments averaged 2.35 auditory distractions/segment.

Through investigating characteristics of SFDs, this preliminary analysis suggests that cognitive distractions occur more often during segments of high team cognitive workload compared to segments of low team cognitive workload. Growing evidence suggests that cognitive factors may influence surgical safety (Suliburk et al., 2019). Given specific cognitive distractions observed during high-workload segments in this study, the role of interpersonal and communication skills likely represent a critical intraoperative area requiring further investigation. In this analysis, we did not demonstrate an impact of auditory distractions, specifically the number of times doors open, on workload. However, beyond the potential for door openings to contribute to auditory distractions, higher counts of door openings could introduce a greater potential for infection during the intraoperative phase, warranting greater attention to the specific surgical phases associated with more door openings. Further work is needed to clarify the impact of the associated distractions on patient outcomes and perioperative care.