Limits...
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.

Kunze N, Weigel C, Vautz W, Schwerdtfeger K, Jünger M, Quintel M, Perl T - J Occup Med Toxicol (2015)

Bottom Line: 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.MCC-IMS shows a significantly lower LOD and LOQ than comparable methods.The exposure of the personnel working in these areas did not exceed recommended limits and therefore adverse health effects are unlikely.

View Article: PubMed Central - PubMed

Affiliation: Department for Anaesthesiology, Centre for Anaesthesiology, Emergency and Intensive Care Medicine, University Medical Centre, University of Göttingen, Robert-Koch-Straße 40, 37075 Göttingen, Germany.

ABSTRACT

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.

No MeSH data available.


Related in: MedlinePlus

Topographic MCC-IMS plot marking the positions and intensities of the monomer and the dimer of sevoflurane at a concentration of 200 ppbv during calibration with the x-axis indicating the inverse ion mobility involt seconds per square centimeter (Vs/cm2) and the y-axis indicating the MCC retention time in seconds (s). Signal intensities are indicated by the peak colour, whereas white indicates lowest and yellow highest signal intensities.
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Fig1: Topographic MCC-IMS plot marking the positions and intensities of the monomer and the dimer of sevoflurane at a concentration of 200 ppbv during calibration with the x-axis indicating the inverse ion mobility involt seconds per square centimeter (Vs/cm2) and the y-axis indicating the MCC retention time in seconds (s). Signal intensities are indicated by the peak colour, whereas white indicates lowest and yellow highest signal intensities.

Mentions: Room air measurements were performed during paediatric anaesthesia and in the PACU of the University Medical Centre using a MCC-IMS device (Leibniz-Institut für Analytische Wissenschaften – ISAS – e.V., Dortmund, Germany). The fundamentals of ion mobility spectrometry are described in detail in literature, as well as the principle of gas sample analyses by the MCC-IMS technology has been described in detail previously [15]. We therefore only give a short overview on its principle (see Table 1 for the specifications of the MCC-IMS used for this study): Gas samples are drawn directly by the MCC-IMS’s membrane pump and through an 8 ml sample loop consisting of Teflon. A six-port valve (ISAS, Dortmund, Germany) enables its introduction into the multi-capillary column. After pre-separation, the gas samples are lead into the ionization chamber, where they are ionized through charge transfer from prior ionized reactant ions. A shutter grid that opens for defined range of time (300 μs) separates drift region and ionization region. Ionized molecules pass the shutter grid and get accelerated in a weak electric field towards the detector (Faraday plate) along the drift region of the MCC-IMS. On their way to the detector, ions are separated through collision with drift gas molecules moving in the opposite direction, with their individual velocities depending on size, shape and charge of the molecules. Drift times are measured and the respective drift velocities are calculated for the known drift distances. Ion mobility is calculated by normalizing the drift velocities to the known electrical field. In a last step the reduced ion mobility, which is characteristic to an ion and independent on the experimental conditions, is calculated by normalization to temperature and pressure [22]. In the drift region ions are moving through an external electric field with positive or negative polarity. We used the mode for the detection of the negative ions of sevoflurane. Analyses of the detected MCC-IMS signals were performed using the BB_IMSAnalyse software (Version 1.0, ISAS, Dortmund, Germany). With the MCC working at a temperature of 40°C the peak position of the sevoflurane monomer was found to be 1/K0 = 0.635 Vs/cm2 at 7 s retention time (see Figure 1). Descriptive statistical analyses and statistical plots were done using statistical software (Statistica 10, StatSoft Inc., Tulsa, USA).Table 1


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.

Kunze N, Weigel C, Vautz W, Schwerdtfeger K, Jünger M, Quintel M, Perl T - J Occup Med Toxicol (2015)

Topographic MCC-IMS plot marking the positions and intensities of the monomer and the dimer of sevoflurane at a concentration of 200 ppbv during calibration with the x-axis indicating the inverse ion mobility involt seconds per square centimeter (Vs/cm2) and the y-axis indicating the MCC retention time in seconds (s). Signal intensities are indicated by the peak colour, whereas white indicates lowest and yellow highest signal intensities.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4379543&req=5

Fig1: Topographic MCC-IMS plot marking the positions and intensities of the monomer and the dimer of sevoflurane at a concentration of 200 ppbv during calibration with the x-axis indicating the inverse ion mobility involt seconds per square centimeter (Vs/cm2) and the y-axis indicating the MCC retention time in seconds (s). Signal intensities are indicated by the peak colour, whereas white indicates lowest and yellow highest signal intensities.
Mentions: Room air measurements were performed during paediatric anaesthesia and in the PACU of the University Medical Centre using a MCC-IMS device (Leibniz-Institut für Analytische Wissenschaften – ISAS – e.V., Dortmund, Germany). The fundamentals of ion mobility spectrometry are described in detail in literature, as well as the principle of gas sample analyses by the MCC-IMS technology has been described in detail previously [15]. We therefore only give a short overview on its principle (see Table 1 for the specifications of the MCC-IMS used for this study): Gas samples are drawn directly by the MCC-IMS’s membrane pump and through an 8 ml sample loop consisting of Teflon. A six-port valve (ISAS, Dortmund, Germany) enables its introduction into the multi-capillary column. After pre-separation, the gas samples are lead into the ionization chamber, where they are ionized through charge transfer from prior ionized reactant ions. A shutter grid that opens for defined range of time (300 μs) separates drift region and ionization region. Ionized molecules pass the shutter grid and get accelerated in a weak electric field towards the detector (Faraday plate) along the drift region of the MCC-IMS. On their way to the detector, ions are separated through collision with drift gas molecules moving in the opposite direction, with their individual velocities depending on size, shape and charge of the molecules. Drift times are measured and the respective drift velocities are calculated for the known drift distances. Ion mobility is calculated by normalizing the drift velocities to the known electrical field. In a last step the reduced ion mobility, which is characteristic to an ion and independent on the experimental conditions, is calculated by normalization to temperature and pressure [22]. In the drift region ions are moving through an external electric field with positive or negative polarity. We used the mode for the detection of the negative ions of sevoflurane. Analyses of the detected MCC-IMS signals were performed using the BB_IMSAnalyse software (Version 1.0, ISAS, Dortmund, Germany). With the MCC working at a temperature of 40°C the peak position of the sevoflurane monomer was found to be 1/K0 = 0.635 Vs/cm2 at 7 s retention time (see Figure 1). Descriptive statistical analyses and statistical plots were done using statistical software (Statistica 10, StatSoft Inc., Tulsa, USA).Table 1

Bottom Line: 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.MCC-IMS shows a significantly lower LOD and LOQ than comparable methods.The exposure of the personnel working in these areas did not exceed recommended limits and therefore adverse health effects are unlikely.

View Article: PubMed Central - PubMed

Affiliation: Department for Anaesthesiology, Centre for Anaesthesiology, Emergency and Intensive Care Medicine, University Medical Centre, University of Göttingen, Robert-Koch-Straße 40, 37075 Göttingen, Germany.

ABSTRACT

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.

No MeSH data available.


Related in: MedlinePlus