ABSTRACT
INTRODUCTION: Literature has shown cognitive overload which can negatively impact learning and clinical performance in surgery. We investigated learners' cognitive load during simulation-based trauma team training using an objective digital biomarker. METHODS: A cross-sectional study was carried out in a simulation center where a 3-h simulation-based interprofessional trauma team training program was conducted. A session included three scenarios each followed by a debriefing session. One scenario involved multiple patients. Learners wore a heart rate sensor that detects interbeat intervals in real-time. Low-frequency/high-frequency (LF/HF) ratio was used as a validated proxy for cognitive load. Learners' LF/HF ratio was tracked through different phases of simulation. RESULTS: Ten subjects participated in 12 simulations. LF/HF ratios during scenario versus debriefing were compared for each simulation. These were 3.75 versus 2.40, P < 0.001 for scenario 1; 4.18 versus 2.77, P < 0.001 for scenario 2; and 4.79 versus 2.68, P < 0.001 for scenario 3. Compared to single-patient scenarios, multiple-patient scenarios posed a higher cognitive load, with LF/HF ratios of 3.88 and 4.79, P < 0.001, respectively. CONCLUSIONS: LF/HF ratio, a proxy for cognitive load, was increased during all three scenarios compared to debriefings and reached the highest levels in a multiple-patient scenario. Using heart rate variability as an objective marker of cognitive load is feasible and this metric is able to detect cognitive load fluctuations during different simulation phases and varying scenario difficulties.
