Errors on anaesthetic record charts as a measure of anaesthetic performance during simulated critical incidents

We have measured the performance of 10 trainee anaesthetists during a single simulated anaesthetic during which there was a complex critical incident. Errors in the recording on the anaesthetic charts of the "patient's" oxygen saturation, heart rate, systolic and diastolic arterial pressures and end-tidal carbon dioxide concentrations were used as a measure of mental workload and hence performance. The critical incident was designed to be stressful and contained, in sequence, episodes of hypotension, arrhythmia and bronchospasm. Chart recording errors increased markedly during the critical incident (P < 0.01) and decreased subsequently when the "patient" had stabilized. More than 22% of the values charted during the simulation were in error by more than 25% of the real value, and errors in excess of 100% of the actual value were recorded. There was no evidence of a tendency to consistently underestimate the magnitude of abnormal values. This method is appropriate for assessing the performance of groups of anaesthetists during simulated critical incidents. It also raises questions on the accuracy of anaesthetic record charts when recording critical incidents.