Comparison of a perfusion simulator to a clinical operating room: evaluation of eye tracking data and subjective perception. A pilot study.

BACKGROUND: With the aim of evaluating the perfusion simulator at the German Heart Center Berlin, similarity between simulation and clinical operation room (OR) was investigated regarding subjective perception and eye movement. METHODS: Eight perfusionists performed an operation on the heart-lung machine (HLM) wearing eye tracking glasses, each in real OR and simulator. The three most important phases for perfusionists (going on bypass, cardioplegia administration and coming off bypass) were considered. Additional to eye tracking data as objective measure, questionnaires were completed, and interviews conducted afterwards. RESULTS: The structure of simulator and real OR is perceived as basically the same. Yet there are differences in the HLM-models used and the temporal sequence. Different perception of both situations is reported in interviews and reflected in significant differences in the rating scales (NASA-TLX) on three of six subscales. In eye tracking data, certain AOIs could be identified for the individual phases, both in OR and simulator-an indication of fundamental similarity. However, differences regarding the proportions of the individual AOIs, especially in the first and third phase, are leading to the assumption that the simulator, and especially the simulation process, is only valid to a limited extent regarding subjective perception and eye tracking data. CONCLUSION: The use of the simulator for (advanced) training is accepted and explicitly requested by perfusionists. Yet further research is needed to identify the decisive factors (like simulation duration or additional tasks) for a valid execution in the simulator. Furthermore, a larger sample size should be regarded to allow statistical analysis.

Simulation-based training of critical events during cardiopulmonary bypass: importance of a critical events checklist.

OBJECTIVES: Evaluation of critical events training for clinical perfusionists is necessary to improve this educational approach. Critical events checklists are effective in reducing clinical complications, but should be tested in a simulation environment first. Individual behavior and stress response of clinical perfusionists during simulated critical events on cardiopulmonary bypass have not been evaluated yet. This study focuses on the evaluation of critical events training and critical events checklists in simulated cardiopulmonary bypass. METHODS: A total of 19 clinical perfusionists from a single hospital took part in two simulated critical event scenarios. Clinical perfusionist behavior and physiological responses were recorded using eye tracking, heart rate variability, video, and audio. In addition, workloads were determined and participants were interviewed. RESULTS: Relevant areas of interest were identified for each simulation phase. During critical event detection and subsequent decision-making, areas of interest hits and fixation durations varied with the use of a critical events checklist. Times to decision were shorter, decision quality was higher, and temporal workload was increased when the checklist was used. Evaluation of selected heart rate variability measures revealed a good correlation with pupil diameters. CONCLUSION: Evaluation of critical events during simulated cardiopulmonary bypass shows that the scenario is realistic and relevant for clinical practice. Integrating a critical events checklist improves the probability of correct decision-making and shortens the correct decision time. Temporal workload is increased when using a checklist. Eye tracking and heart rate variability are well suited to evaluate participants' behaviors and stress levels. All participants welcomed simulation training for critical incidents.

Evaluation of attention, perception, and stress levels of clinical cardiovascular perfusionists during cardiac operations: a pilot study.

BACKGROUND: Performing cardiopulmonary bypass is a complex task which involves evaluating visual input from patient monitors and technical parameters displayed at the heart-lung machine console as well as reacting to other sensory input. Only few studies are available concerning the competency requirements for clinical cardiovascular perfusionists, including attention, perception, and coping with mental stress. This study aims at evaluating attention, perception, and stress levels of clinical cardiovascular perfusionists during cardiopulmonary bypass. METHODS: Nine clinical cardiovascular perfusionists voluntarily offered to participate in the study. Participants were asked to wear Tobii 2 eye-tracking glasses throughout the procedures. Specific time points were analyzed (cardiopulmonary bypass on, initial cardioplegia delivery, steady state, cross-clamp off, and weaning from cardiopulmonary bypass). Data acquisition was supplemented by participants' self-evaluation regarding their stress levels and by National Aeronautics and Space Administration Task Load Index (NASA TLX) questionnaires. RESULTS: Seven datasets were sufficient to be evaluated. The clinical cardiovascular perfusionists' professional experience ranged from 0.5 to 24 years. Evaluation of eye-tracking data revealed large variations in areas of interest hits, fixation, and dwell times. Across all phases, the venous reservoir, mean arterial pressure, arterial pump display, cardioplegia control, and data management system received the highest levels of attention. Pupil diameter measurements increased at start of cardiopulmonary bypass, cardioplegia delivery, and weaning off, but returned to base level during steady state. Clinical cardiovascular perfusionists' self-evaluation showed that subjective stress level was highest at the start and the end of the procedure. NASA TLX questionnaires revealed medium-to-high mental and temporal workloads, but low physical workloads. Performance, effort, and frustration indices showed medium workloads. CONCLUSION: During cardiopulmonary bypass, perfusionists are subjected to stress. Peak stress levels were highest during start and end of cardiopulmonary bypass. Furthermore, visual attention and perception varied between the operative phases. Further studies are indicated to evaluate the design of heart-lung machines and stress-coping strategies during cardiopulmonary bypass.