Prevention of atmospheric contamination during isoflurane sedation

With a view to minimising staff exposure to exhaled isoflurane which had been used for sedation, we assessed the efficacy of either activated charcoal adsorption or active or passive mechanical scavenging systems in intensive care units (ICUs). Personal monitoring revealed minimal exposure of staff to the sedating agent. Infra-red analyses of ambient air rarely showed isoflurane levels greater than 26 ppm, with mean concentrations of around 1 ppm. Small spillages during vaporiser filling were of no polluting significance. The activated charcoal adsorbers functioned highly efficiently for at least 12-hour periods. With simple scavenging techniques, atmospheric isoflurane contamination during sedation with the agent remains well within an acceptable range and is unlikely to pose a health risk to nursing and medical staff.