Active Gas Scavenging is Unnecessary When Using the AnaConDa Volatile Agent Delivery System

The AnaConDa filter system has been used in intensive care units (ICUs) to deliver low concentrations of volatile anaesthetic agents to treat severe airflow obstruction and for sedation. The manufacturer and a recently published review recommend the use of a scavenging system with the device. It is unclear from the literature what levels of volatile agent staff are exposed to when the device is being used in ICU without a scavenger. We carried out an observational study requested by the local occupational health department to measure the levels of ICU staff exposure to isoflurane when the AnaConDa delivery system was used to treat asthma. This study was carried out using an ambient air analyser while the patient was receiving therapeutic levels of isoflurane via the AnaConDa device. We conclude that gas scavenging may not be necessary when using the AnaConDa device to deliver therapeutic doses of isoflurane.