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Physiological synchronization and entropy as measures of team cognitive load
Roger D Dias1, Marco A Zenati2, Ronald Stevens3
1STRATUS Center for Medical Simulation, Brigham and Women's Hospital, USA; Department of Emergency Medicine, Harvard Medical School, USA.
Journal of Biomedical Informatics
|July 12, 2019
Summary
This study introduces a new method to measure team cognitive load in real-time during surgery using heart rate variability. The approach revealed shifts in team synchronization and organization, especially during critical events, improving patient safety insights.
Area of Science:
- Medical Physiology
- Human Factors Engineering
- Team Performance Science
Background:
- The operating room (OR) is a complex, high-risk environment demanding significant cognitive effort from surgical teams.
- Cognitive overload in OR staff can negatively impact team performance and patient safety.
- Existing methods for assessing team cognitive load are limited in real-time, dynamic measurement.
Purpose of the Study:
- To investigate the feasibility of a novel methodological approach for characterizing dynamic changes in team cognitive load.
- To measure team cognitive load by assessing synchronization and entropy of heart rate variability (HRV) parameters during real-life cardiac surgery.
- To develop and validate a technique for real-time assessment of team physiological synchronization.
Main Methods:
- Utilized unobtrusive wearable heart rate sensors to capture interbeat intervals (IBI) from surgeon, anesthesiologist, and perfusionist.
- Developed symbolic representations of Individual Cognitive State (ICS) and Team Cognitive State (TCS) based on IBI data.
- Calculated Shannon's entropy of HRV to estimate team organization and detect fluctuations related to cognitive demands and situational events.
Main Results:
- Successfully captured dynamic changes in team cognitive load using HRV synchronization and entropy during cardiac surgery.
- Demonstrated that cognitive load patterns shifted rapidly following a near-miss medication event, leading to a more organized and synchronized team state.
- The distribution of TCS symbols provided insights into temporal states and dynamic changes in team cognitive load.
Conclusions:
- The described methodological approach offers a feasible and novel technique for assessing team cognitive load and physiological synchronization in real-time.
- This method can be applied to various team-based environments beyond the OR to understand team dynamics.
- Further research is needed to gather additional validity evidence for the proposed team cognitive load measurement methods.
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