Wilkes Antony R
Department of Anaesthetics and Intensive Care Medicine, Wales College of Medicine, Cardiff University, Heath Park, Cardiff CF14 4XN, Wales, UK.
Expert Rev Med Devices. 2005 May;2(3):319-26. doi: 10.1586/17434440.2.3.319.
During anesthesia, a breathing system may be used for more than one patient. Any microbes expelled by one patient, whether gasborne in the form of droplets or liquidborne in sputum, should be prevented from entering the breathing system. Breathing system filters are intended to reduce the risk of cross infection during anesthesia and intensive care from these routes. The Medicines and Healthcare products Regulatory Agency published a report in 2004 that included data on the gasborne filtration performance of 104 different filters available on the UK market. A wide range in filtration performance was found. Filters intended for use with pediatric patients do not appear to offer the same level of protection as those intended for use with adult patients, despite the lower flow used to challenge these filters. Recent government initiatives to reduce the prevalence of tuberculosis and hepatitis C in England have again focused interest on the ability of filters to reduce the risk of cross infection from these particular microbes arising from patients who may not be aware that they are harboring the disease. Currently, there are no requirements for the level of filtration that breathing system filters have to provide, either in standards or from professional bodies.
