Sevoflurane output from the Oxford Miniature Vaporizer in drawover mode

The sevoflurane output from the Oxford Miniature Vaporizer (OMV) was measur ed in a series of bench tests in a drawover system. Using a range of settin gs on two OMVs in series, output ranged from 0.5 to 5.9% with a 600 ml tida l volume at a rate of 12 breaths/min produced by a Penlon Multivent. The OM Vs' output was steady over 40 minutes. In rests with tidal volumes Ranging from 300 ml to 1200 ml, the OMVs' output was lower at higher minute volumes . When continuous flow of carrier gas at 7.2 l/min was used, the output was lower than at the equivalent intermittent flow rate. Using two OMVs with a drawover system appears to be a feasible technique for the induction and m aintenance of sevoflurane anaesthesia. Clinical tests of sevoflurane drawov er anaesthesia ale now required so that the advantages of sevoflurane can g ain wider application in field and military anaesthesia.