Hypoxic gas mixture delivery due to malfunctioning inlet port of a Select-a-Tec vaporiser manifold

作者:John Riendl 刊名: 上传者:郭庆彪



CORRESPONDENCE 431 Hypoxic gas m&ture delivery particular problem, yet I cannot help wondering whether certain design features could be modified to further due to malfunctioning inlet port minimize hypoxic risk. of a Select-a-Tec vaporiser John Riendl MD FRcr'c manifold Department of Anaesthesia Dr. Everett Chalmers Hospital To the Editor: Frederieton, New Brunswick A potentially serious malfunction of an OHMEDA E3B 5N5 Modulus I gas machine occurred which allowed a hypoxic Present address: mixture to be delivered to a patient. At the time el the Department of Anaesthesia incident, the source of the problem was identified as a Nanaimo Regional Hospital malfunctioning inlet valve of the Select-a-Tee SM vapor- Nanaimo, British Columbia izer manifold. When a mounted Tee 4 vaporizer was set to V9S 2B7 a low concentration (0.25 per cent) the valve partially occluded the gas flow. This caused a back pressure which EDITORIAL NOTE preferentially dropped the oxygen flow while maintaining OHMEDA, Madison, Wisconsin, submitted the follow- the N20 flow. Valve replacement corrected the problem. ing Alert for puhli.cation in association with the above No patient injury occurred. letter. The Alert has been reproduced without change. Subsequent investigations by OHMEDA have revealed that this situation can occur when the two springs in the Urgent - Medical Device Safety Alert vaporizer manifold port valve are reversed (due to a servicing error) and the vaporizer setti