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

Abstract

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.

The scavenging of volatile anesthetic agents in the cardiovascular intensive care unit environment: a technical report

“…However, in a recent case series by Marbini et al, they assessed the degree of ICU environmental pollution with the AnaConDa device using isoflurane with only ten room air exchanges per hour and no additional active scavenging. 23 The authors showed peak isoflurane levels of 50 ppm at the expired port, which fell to less than 2 ppm around the patient's head and the predicted nursing area. A second study by Sackey et al in 15 patients during ICU sedation for 12-96 hr looked at ambient isoflurane pollution and consumption utilizing active scavenging and four room air exchanges per hour.…”

Sevoflurane therapy for life-threatening acute severe asthma: a case report

“…Only 2-33 parts per million (ppm) during a 12-hr shift were detected (highest values were measured 3 cm adjacent to the ventilator exhaust port). 14 In another study, spectrophotometric measurements showed 0.1-0.2 ppm at 50 cm from the patient's head. These values are significantly below internationally recommended exposure limits.…”

“…These values are significantly below internationally recommended exposure limits. [12][13][14] Nevertheless, a special scavenging system (CONTRAfluran TM ) is available, and its use seems to be sufficient. 22 Finally, signs of MH should always be monitored and therapy stopped if this complication develops, Administration of intravenous dantrolene sodium and application of supportive therapy may also be required (Table 4).…”

“…With this unique technique, approximately 90% of the delivered agent can be recycled, obviating the need for any active scavenging system and making the treatment safe and cost effective. [12][13][14] Written informed consent was obtained from the patient for publication of this case report and the accompanying images.…”

Sedation with sevoflurane in postoperative cardiac surgery: influence on troponin T and creatinine values

“…The safe use, in terms of minimal contamination, of the AnaConDa ® with a scavenging system in the ICU environments (values not exceeded 1 ppm) has been described (27). Moreover, its safe use without any scavenging system has been demonstrated (28), making this unnecessary according to some authors (29). In terms of efficiency, the direct costs of the use of sevoflurane as sedative agent are significantly lower when compared to midazolam (30).…”