An integrated system for significant anaesthetic events monitoring.

Patient safety assessment in anaesthesia increasingly relies on the monitoring of frequent but merely undesirable events, like hypotension. We report on the design and implementation of such a monitoring system, where 8032 patients were included over a three years period. Thirty two 'Significant Anaesthetic Events' were defined and their occurrence was routinely collected for each patient. A total of 2106 significant anaesthetic events were reported. The data were analysed using control charts, which showed that an undesirable event was recorded in 1 out of 4 interventions. The control chart showed that the incidence of significant anaesthetic events was out of the expected boundaries during one month. The system sensitivity to change in the frequency of significant anaesthetic events was investigated by a controlled intervention, designed to increase the incidence of bradycardia by changing anxyolitic medication. During the intervention, the incidence of bradycardia doubled, while the incidence of other undesirable events was not affected. The system described for the collection of significant anaesthetic events was easy to set up, sensitive to changes and provided valuable tools in performance monitoring.