Sevoflurane Output in the Isoflurane/Halothane Diamedica Draw-over Vaporiser

Abstract

Introduction: Draw-over anaesthesia remains an attractive option for conduct of anaesthesia in austere conditions. The Diamedica Draw-over Vaporiser (DDV) is a modern draw-over vaporiser and has separate models for isoflurane/halothane and sevoflurane. Materials and Methods: A laboratory study was done to measure sevoflurane output in an isoflurane/halothane DDV. We did 3 series of experiments with the isoflurane/halothane DDV. We measured anaesthetic agent output in both push-over and draw-over setups, and at minute ventilation of 6 L/min and 3 L/min. Series 1 experiment was done with isoflurane in the DDV at ambient temperature of 20°C. Series 2 experiment was done with sevoflurane in the DDV at ambient temperature of 20°C. Series 3 experiment was done with sevoflurane in the DDV and with the DDV placed in a water bath of 40°C. Results: The sevoflurane output was found to be two-thirds of the isoflurane/halothane DDV dial setting at ambient temperature of 20°C. With the DDV in a 40°C water bath, the sevoflurane output was found to be about the isoflurane/halothane DDV dial settings. Conclusion: In our experiment, we show that it is possible to use sevoflurane in an isoflurane/halothane DDV. Key words: Anaesthetics, Disaster medicine, Inhalation, Military medicine