INTRODUCTIONDraw-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 METHODSA 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.

RESULTSThe 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.

CONCLUSIONIn our experiment, we show that it is possible to use sevoflurane in an isoflurane/halothane DDV.

Anesthesia, Inhalation ; instrumentation ; methods ; Anesthetics, Inhalation ; administration & dosage ; Halothane ; Humans ; Isoflurane ; Methyl Ethers ; administration & dosage ; Nebulizers and Vaporizers ; Temperature

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