Multi-capillary column-ion mobility spectrometry (MCC-IMS) as a new method for the quantification of occupational exposure to sevoflurane in anaesthesia workplaces: an observational feasibility study

BACKGROUND: Occupational exposure to sevoflurane has the potential to cause health damage in hospital personnel. Workplace contamination with the substance mostly is assessed by using photoacoustic infrared spectrometry with detection limits of 10 ppbv. Multi-capillary column-ion mobility spectrometry (MCC-IMS) could be an alternative technology for the quantification of sevoflurane in the room air and could be even more accurate because of potentially lower detection limits. The aim of this study was to test the hypothesis that MCC-IMS is able to detect and monitor very low concentrations of sevoflurane (<10 ppbv) and to evaluate the exposure of hospital personnel to sevoflurane during paediatric anaesthesia and in the post anaesthesia care unit (PACU). METHODS: A MCC-IMS device was calibrated to several concentrations of sevoflurane and limits of detection (LOD) and quantification (LOQ) were calculated. Sevoflurane exposure of hospital personnel was measured at two anaesthesia workplaces and time-weighted average (TWA) values were calculated. RESULTS: The LOD was 0.0068 ppbv and the LOQ was 0.0189 ppbv. During paediatric anaesthesia the mean sevoflurane concentration was 46.9 ppbv (8.0 - 314.7 ppbv) with TWA values between 5.8 and 45.7 ppbv. In the PACU the mean sevoflurane concentration was 27.9 ppbv (8.0 – 170.2 ppbv) and TWA values reached from 8.3 to 45.1 ppbv. CONCLUSIONS: MCC-IMS shows a significantly lower LOD and LOQ than comparable methods. It is a reliable technology for monitoring sevoflurane concentrations at anaesthesia workplaces and has a particular strength in quantifying low-level contaminations of sevoflurane. The exposure of the personnel working in these areas did not exceed recommended limits and therefore adverse health effects are unlikely

Occupational exposure to sevoflurane during cardiopulmonary bypass

Volatile anaesthetic agents are widely used for maintenance of anaesthesia in all kinds of surgical procedures. Despite the implementation of measures such as adequate ventilation of the operating room and the use of efficient scavenging systems, concern remains about the risks for occupational exposure, especially in situations associated with an increased risk of anaesthetic gas waste, such as with the use of volatile anaesthetic agents on cardiopulmonary bypass. The present contribution reports the results of a preliminary safety assessment involving measurements of sevoflurane concentrations in the ambient air of a cardiac surgery operating room. In 22 cardiac surgical procedures with cardiopulmonary bypass (11 with open and 11 with closed venous reservoir), measurements of trace concentrations were obtained every 10 min at the following sites: at the outlet of the oxygenator, at the outlet of the cardiotomy reservoir, in the breathing zone of the perfusionist and above the surgical field. The concentrations were measured on-line using a photoacoustic infrared spectrometer. Mean sevoflurane waste concentrations remained consistently below the recommended target value of 4.68 ppm throughout the observation period at the different measurement sites. These results indicate that, with the use of sevoflurane on cardiopulmonary bypass, the recommended levels for occupational exposure are not exceeded, provided adequate operation room ventilation and waste gas scavenging is performed