Environmental and biological measurements of isoflurane and sevoflurane in operating room personnel

Veterinarians exposed to inhaled anesthetic present chromosome damage, apoptosis and cell cycle changes

This cross-sectional study evaluated, for the first time, DNA damage, viability, and cell death of lymphocytes and cell cycle phases of mononuclear and polymorphonuclear cells in veterinarians exposed to the volatile anesthetic isoflurane. Veterinarians who were occupationally exposed to isoflurane (exposed group; n = 20) and matched-unexposed individuals (volunteers without occupational exposure; n = 20) were enrolled in the study. DNA damage was assessed in lymphocytes by micronucleus (MN) and phosphorylated histone gamma-H2AX (γ-H2AX). Cell viability, cytotoxicity, and the cell cycle were evaluated by flow cytometry. Isoflurane was detected in urine samples by headspace gas chromatography-mass spectrometry. Compared with unexposed subjects, veterinarians occupationally exposed to isoflurane (25.7 ± 23.7 μg/L urine) presented statistically higher MN frequencies, lymphocytic apoptosis rates, and numbers of polymorphonuclear cells in the G0/G1 stage. Additionally, the exposed group presented statistically lower proportions of viable lymphocytes and G2/M polymorphonuclear cells. Our findings indicate that veterinarians who are frequently exposed to inhaled anesthetic exhibit chromosomal and cell damage in addition to changes in peripheral blood cell proliferation.

Exposure to anesthetic gases in the operating rooms and assessment of non-carcinogenic risk among health care workers

Health care workers employed operating room in hospital and health centers are unavoidably exposed to inhaling toxic gases, including isoflurane and sevoflurane. Chronic contact with these gases increases the risk of spontaneous abortion, congenital anomalies and cancers. Risk assessment is an important tool in predicting the possible risk to personnel's health. Therefore, this study was conducted with the aim of determining the concentration of isoflurane and sevoflurane gas in the air of the operating room and estimating the non-carcinogenic risk caused by them. In this descriptive-cross-sectional study, according to the occupational method (OSHA 103), 23 samples (isoflurane and sevoflurane) were collected in the air of operating rooms of four selected hospitals in Ahvaz city by using SKC sampling pumps and sorbent tube (Anasorb 747). The samples were determined by used to gas chromatography with a flame ionization detector (GC/FID). Statistical analysis, including the Kruskal-Wallis test, was used to compare the average concentration of anesthetic gases, and the one-sample t-test was used to compare the average with the standard level. In all analyses, the significance level was 0.05, which was performed by SPSS version 22 software. Result of this study showed that the average concentration of isoflurane in private and general hospitals were 23.636 and 17.575 ppm, respectively. Also, the average level of sevoflurane were 1.58 and 7.804 ppm. According to the results the mean amount of anesthetic gases was within the range recommended by Iran's Occupational and Environmental Health Center and the permissible threshold limit provided by ACGIH. In addition, non-cancer risks from occupational exposure to isoflurane and sevoflurane in selected private and general hospitals were acceptable (HQ < 1). Although the results show that overall occupational exposure to anesthetic gases is less than acceptable but long-term exposure to anesthetic gases may endanger the health of operating room staffs. Therefore, it is recommended to implement some technical controls, including regular inspection of ventilation systems, the use of advanced ventilation systems with high cleaning power, continuous control of anesthesia devices in terms of leakage, and periodic training of related staff.

A straightforward method for determination of the sevoflurane metabolite hexafluoroisopropanol in urinary occupational medical samples by headspace-gas chromatography mass spectrometry

Biological monitoring of the unmodified sevoflurane and its metabolite hexafluoroisopropanol (HFIP) in urine samples was proposed to determine the individual exposure levels of the medical staff. In this study, a method for simultaneous determination of both compounds in urine using static headspace-gas chromatography-mass spectrometry (HS-GC-MS) was developed. The method is linear over a broad concentration range from 1 to 1000 µg/L (r2 > 0.999) and shows high precision. Limits of quantification (LOQ) are 0.6 µg/L for sevoflurane and 3 µg/L for HFIP, representing an excellent sensitivity without the necessity of analyte enrichment. The method was successfully applied in a German pilot-study to monitor both compounds in samples from medical personnel working in operating theatres. Urinary concentrations of HFIP ranged between < LOQ and 145 µg/L, while sevoflurane was below the LOD in all samples.

[Working in the Operating Theatre - What does the Surgeon Need to Know About Occupational Medicine?]

Surgery is associated with numerous health hazards for the staff.The aim of this article is to show the risks to the health and ability to work of surgical staff and the possibilities for improving occupational health and safety in terms of behavioural and situational prevention, as well as secondary and tertiary prevention, especially with regard to cooperation with the occupational physician.The brief narrative overview is based on the author's own occupational medicine, surgery and interdisciplinary experience from daily practice and selective references from the current medical-scientific literature, using the example of the operating theatre work area.The possible activity-related health hazards and the risks to the working ability of medical staff as well as the possibilities for occupational health and safety in the sense of behavioural and situational prevention are an important matter in the interdisciplinary status of surgery that should not be underestimated (since it is also partly determined by law). Above all, this discipline must responsibly dedicate itself to the points of contact with occupational medicine (in addition to acquiring its own knowledge from the surgical side).

Occupational Exposure to Halogenated Anaesthetic Gases in Hospitals: A Systematic Review of Methods and Techniques to Assess Air Concentration Levels

Objective During the induction of gaseous anaesthesia, waste anaesthetic gases (WAGs) can be released into workplace air. Occupational exposure to high levels of halogenated WAGs may lead to adverse health effects; hence, it is important to measure WAGs concentration levels to perform risk assessment and for health protection purposes. Methods A systematic review of the scientific literature was conducted on two different scientific databases (Scopus and PubMed). A total of 101 studies, focused on sevoflurane, desflurane and isoflurane exposures in hospitals, were included in this review. Key information was extracted to provide (1) a description of the study designs (e.g., monitoring methods, investigated occupational settings, anaesthetic gases in use); (2) an evaluation of time trends in the measured concentrations of considered WAGs; (3) a critical evaluation of the sampling strategies, monitoring methods and instruments used. Results Environmental monitoring was prevalent (68%) and mainly used for occupational exposure assessment during adult anaesthesia (84% of cases). Real-time techniques such as photoacoustic spectroscopy and infrared spectrophotometry were used in 58% of the studies, while off-line approaches such as active or passive sampling followed by GC-MS analysis were used less frequently (39%). Conclusions The combination of different instrumental techniques allowing the collection of data with different time resolutions was quite scarce (3%) despite the fact that this would give the opportunity to obtain reliable data for testing the compliance with 8 h occupational exposure limit values and at the same time to evaluate short-term exposures.

Chemical risk in hospital settings: Overview on monitoring strategies and international regulatory aspects

Chemical risk in hospital settings is a growing concern that health professionals and supervisory authorities must deal with daily. Exposure to chemical risk is quite different depending on the hospital department involved and might origin from multiple sources, such as the use of sterilizing agents, disinfectants, detergents, solvents, heavy metals, dangerous drugs, and anesthetic gases. Improving prevention procedures and constantly monitoring the presence and level of potentially toxic substances, both in workers (biological monitoring) and in working environments (environmental monitoring), might significantly reduce the risk of exposure and contaminations. The purpose of this article is to present an overview on this subject, which includes the current international regulations, the chemical pollutants to which medical and paramedical personnel are mainly exposed, and the strategies developed to improve safety conditions for all healthcare workers.

Probabilistic health risk assessment of occupational exposure to isoflurane and sevoflurane in the operating room

Risk assessment is an important tool in predicting the possible risk to health. It heightens awareness by estimating the probability of adverse health effects in humans who are exposed to chemicals in the course of their work. Therefore, the present work aims to determine the occupational exposure of operating room staff to the volatile anesthetic gases, isoflurane and sevoflurane, and estimates non-cancer risk using the United States Environmental Protection Agency method. Air samples from the breathing zone of staff members were collected using the Occupational Safety and Health Administration Method 103 and analyzed using gas chromatography-mass spectroscopy. The results indicate that the measured concentrations of isoflurane and sevoflurane are below the National Institute of Occupational Safety and Health standard (2 ppm) for technicians and nurses, but not for anesthesiologists and surgeons. Moreover, the estimated non-cancer risk due to isoflurane is above the acceptable value for anesthesiologists (but acceptable for other occupational categories). A sensitivity analysis indicates that exposure time has the most effect on calculated risk (53.4%). Occupational exposure to anesthetic gases may endanger the health of operating room personnel. Therefore, control measures, such as daily testing of anesthetic devices, ensuring the effectiveness of ventilation systems, advanced scavenging methods, and regular training of staff are highly recommended.

Comparison of 3 Methods to Assess Occupational Sevoflurane Exposure in Abdominal Surgeons: A Single-Center Observational Pilot Study

BACKGROUND

Studies demonstrated that operating room personnel are exposed to anesthetic gases such as sevoflurane (SEVO). Measuring the gas burden is essential to assess the exposure objectively. Air pollution measurements and the biological monitoring of urinary SEVO and its metabolite hexafluoroisopropanol (HFIP) are possible approaches. Calculating the mass of inhaled SEVO is an alternative, but its predictive power has not been evaluated. We investigated the SEVO burdens of abdominal surgeons and hypothesized that inhaled mass calculations would be better suited than pollution measurements in their breathing zones (25 cm around nose and mouth) to estimate urinary SEVO and HFIP concentrations. The effects of potentially influencing factors were considered.

METHODS

SEVO pollution was continuously measured by photoacoustic gas monitoring. Urinary SEVO and HFIP samples, which were collected before and after surgery, were analyzed by a blinded environmental toxicologist using the headspace gas chromatography-mass spectrometry method. The mass of inhaled SEVO was calculated according to the formula mVA = cVA·(Equation is included in full-text article.)·t·ρ VA aer. (mVA: inhaled mass; cVA: volume concentration; (Equation is included in full-text article.): respiratory minute volume; t: exposure time; and ρ VA aer.: gaseous density of SEVO). A linear multilevel mixed model was used for data analysis and comparisons of the different approaches.

RESULTS

Eight surgeons performed 22 pancreatic resections. Mean (standard deviation [SD]) SEVO pollution was 0.32 ppm (0.09 ppm). Urinary SEVO concentrations were below the detection limit in all samples, whereas HFIP was detectable in 82% of the preoperative samples in a mean (SD) concentration of 8.53 µg·L (15.53 µg·L; median: 2.11 µg·L, interquartile range [IQR]: 4.58 µg·L) and in all postoperative samples (25.42 µg·L [21.39 µg·L]). The mean (SD) inhaled SEVO mass was 5.67 mg (2.55 mg). The postoperative HFIP concentrations correlated linearly to the SEVO concentrations in the surgeons' breathing zones (β = 216.89; P < .001) and to the calculated masses of inhaled SEVO (β = 4.17; P = .018). The surgeon's body mass index (BMI), age, and the frequency of surgeries within the last 24 hours before study entry did not influence the relation between HFIP concentration and air pollution or inhaled mass, respectively.

CONCLUSIONS

The biological SEVO burden, expressed as urinary HFIP concentration, can be estimated by monitoring SEVO pollution in the personnel's individual breathing zone. Urinary SEVO was not an appropriate biomarker in this setting.

Polymorphism in GSTM1 and GSTT1 genes influence DNA damage in personnel occupationally exposed to volatile anaesthetics (VA), from Peshawar, Pakistan

Objectives

The objective of this study was to assess the influence of antioxidant gene GSTM1 and GSTT1 on DNA damage in personnel occupationally exposed to volatile anaesthetics (VA).

Methods

The study groups were composed of 50 exposed subjects (anaesthesia workers) and 49 controls. Blood samples were collected from both subjects. DNA damage was analysed through the comet assay technique. Biomarker genes GSTM1 and GSTT1 were inspected through PCR technique for polymorphism.

Results

The comet assay technique showed that the Total Comet Score (TCS) in exposed subjects was significantly higher (p=0.0001) than the control. Age and smoking had significant effects on TCS in the study groups (p<0.05). Duration of occupational exposure had significant positive correlation (r=0.755, p<0.001) with DNA damage. The null polymorphism in GSTM1 and GSTT1 gene showed a significant effect (p<0.001 and p<0.000) on the DNA damage.

Conclusions

The polymorphism in GSTM1 and GSTT1 gene significantly damage DNA in personnel occupationally exposed to VA.

Genotoxicity of inhalational anesthetics and its relationship with the polymorphisms of GSTT1, GSTM1, and GSTP1 genes

Due to their wide applications, concern exists regarding possible genotoxic effects of inhalational anesthetics (IAs) among operating room personnel. This study was undertaken to examine genotoxic properties of co-exposure to nitrous oxide, sevoflurane, and isoflurane on induction of micronucleus (MN) and chromosomal aberrations (CAs) and to determine whether any associations exist between polymorphisms of GST genes and the level of genomic damage measured by MN and CAs assays. Sixty operating room personnel and 60 unexposed referent nurses were studied. The workers' exposure to the IAs was determined. DNA damage was evaluated by MN and CAs assays. Additionally, the GSTM1, GSTT1, and GSTP1 polymorphisms were detected. The mean concentrations of nitrous oxide, isoflurane, and sevoflurane were found to be 850.92 ± 919.78, 2.40 ± 0.86, and 0.18 ± 0.14 ppm, respectively. The frequency of MN and CAs in the exposed group was significantly higher than that of the non-exposed group. The frequency of MN was significantly higher in referent nurses with null GSTT1, compared to referent nurses with positive GSTT1. The frequency of MN was significantly higher in exposed individuals carrying the combined genotype of GSTT1 (-), GSTM1 (-), and GSTP1 AG as compared with subjects carrying a combination of GSTT1 (+), GSTM1 (+), and GSTP1 AA. Statistically significant associations were noted between exposure to the IAs, gender, and the combination of the three GSTs genotypes with MN frequency. These findings indicate that inhalation exposure to IAs induces genotoxic response and the polymorphisms of GSTs genes might modulate the effect of exposure to IAs on MN.