Occupational exposure to volatile anaesthetics - Epidemiology and approaches to reducing the problem

Long term occupational exposure to trace concentrations of volatile anaesth etics is thought to have adverse effects on the health of exposed personnel . In contrast with halothane - an agent likely to cause mutagenic effects a nd proven to be teratogenic - isoflurane and enflurane have not so far been proved to have adverse effects on the health of personnel exposed long ter m. Data on the newer agents sevoflurane and desflurane are limited. Since p ossible health hazards from long term exposure to inhalational anaesthetics cannot yet be definitively excluded, many Western countries have establish ed limits for exposure. These usually range from 2 to 10 ppm as a time-weig hted average over the time of exposure. A number of investigations have demonstrated that, in operating theatres wi th modern climate control and waste anaesthetic gas scavenging systems, occ upational exposure is unlikely to exceed threshold limits. However, occupat ional exposure from the use of volatile agents in operating theatres with p oor air control - especially during bronchoscopy procedures in paediatric p atients - remains a source of concern. This also holds true for both postan aesthesia care units (PACU) and intensive care units (ICU) lacking proper a ir conditioning and waste gas scavengers. To minimise occupational exposure to volatile anaesthetics, all measures mu st be taken to provide climate control and properly working scavenging devi ces, and ensure sufficient personal skill of the anaesthetist, e.g. during inhalational mask induction. Furthermore, low-flow anaesthesia should be us ed whenever possible. The sole use of intravenous drugs such as propofol in stead of volatile agents, were this possible, would eliminate occupational exposure, but may result in environmental pollution by toxic metabolites (e .g. phenol).