Familiarising anaesthetists with a new drug using the Leiden Anaesthesia Simulator

E. Olofsen, V. Chopra, M.J. Geerts and J.G. Bovill. Department of Anaesthesiology, Leiden University Medical Centre, The Netherlands

Background

Anaesthesia simulators are increasingly being used to train anaesthetists in dealing with situations that are potentially harmful to the patient. Here we describe the use of the full-scale Leiden Anaesthesia Simulator to demonstrate the characteristics of the new opioid remifentanil to anaesthetists.

Methods

The software underlying the Leiden Anaesthesia Simulator consists of models of the cardiovascular and respiratory systems and ECG, blood pressure and plethysmographic waveforms. A pharmacological module determines how the variables of physiological models are affected after administration of drugs. Pharmacodynamic end-points include levels of analgesia, consciousness, neuromuscular blockade, and cardiovascular and respiratory depression. Four scenarios were designed to demonstrate the characteristics of the ultra-short-acting opioid remifentanil. Scenarios addressed 1) post-operative analgesia 2) effects of overdose 3) intravenous line occlusion and 4) use and dosage in patients with cardiac disease.

Results

Results are presented from a simulation session which showed the effects of occlusion of the intravenous line through which remifentanil was being administered. The figure shows the concentrations of remifentanil (remi concn.) and the mean arterial pressure (MAP). After induction of anaesthesia, the intravenous line was intentionally occluded by turning a three-way valve in the wrong direction at the time represented by the first arrow. Surgical incision occurred at the second arrow. The problem of inadequate anaesthesia was detected because the “patient’s” blood pressure increased dramatically at incision. When the three-way valve was opened, the stored remifentanil got flushed into the patient. The rapid elimination of remifentanil is clearly shown by its concentration curve.

Conclusions

The special characteristics of new drugs can be succesfully demonstrated by use of an anaesthesia simulator. This allows anaesthetists to explore “what-happens-if” questions about situations potentially resulting in inadequate anaesthesia or unintentional overdosing.

Acknowledgement

This study was supported by Glaxo-Wellcome.