Sevoflurane Human Biomonitoring in Operating Room Personnel

Study Overview
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Brief Summary
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Sevoflurane is a widely used volatile agent for induction and maintenance of anaesthesia. The administration of sevoflurane involves the risk of occupational exposure. Possible negative implications of chronic occupational exposure to sevoflurane are not completely refuted. In Germany no maximum workplace concentration for sevoflurane is defined. This study aims to find out if working conditions of physicians and different anaesthesia techniques effect the extent of occupational exposure to sevoflurane.

Detailed Description
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In this prospective observational trial 7 cohorts of 4 participants each are investigated. The cohorts consist of physicians working at different places in the operating theatre with different occupational exposure to sevoflurane, and one cohort not working in the operating theatre at all. In order to determine the extent of occupational exposure to sevoflurane a human biomonitoring is conducted. Urinary Sevoflurane and its metabolite hexafluoroisopropanol (HFIP) are measured after 3 consecutive working days. UPDATE: After detecting traces of HFIP in all cohorts even in physicians not working in the operating theatre measurements were repeated, more cohorts were added including a negative control and measurements before the study period of 3 consecutive working days were added. UPDATE: For comparison one cohort of patients having undergone sevoflurane anaesthesia was added.

Official Title
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Human Biomonitoring of Operating Room Personnel With Occupational Exposure to the Volatile Anaesthetic Sevoflurane

Conditions
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Occupational Exposure

Intervention / Treatment
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* Diagnostic Test: HFIP and Sevoflurane are measured after 3 consecutive days of work.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Occupational exposure to sevoflurane while conducting sevoflurane anaesthesia/being present during sevoflurane anaesthesia Possible occupational exposure to sevoflurane while working in the operating room/perioperative anaesthesia care unit No occupational exposure to sevoflurane (working outside the operating theatre) Exclusion Criteria: Presence during a mask induction with sevoflurane

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Anaesthesiologists balanced<br>Anaesthesiologists performing balanced anaesthesia with sevoflurane. | Diagnostic Test: HFIP and Sevoflurane are measured after 3 consecutive days of work.<br>* Concentration of hexafluoroisopropanol and Sevoflurane are measured in urine by gas chromatography<br>|
| Anaesthesiologists TIVA<br>Anaesthesiologists performing only total intravenous anaesthesia. | Diagnostic Test: HFIP and Sevoflurane are measured after 3 consecutive days of work.<br>* Concentration of hexafluoroisopropanol and Sevoflurane are measured in urine by gas chromatography<br>|
| Surgeons<br>Surgeons working in the operating room while anaesthesia of the patients is randomly maintained with sevoflurane or propofol. | Diagnostic Test: HFIP and Sevoflurane are measured after 3 consecutive days of work.<br>* Concentration of hexafluoroisopropanol and Sevoflurane are measured in urine by gas chromatography<br>|
| Anaesthesiologists PACU<br>Anaesthesiologists working in the postoperative care unit. | Diagnostic Test: HFIP and Sevoflurane are measured after 3 consecutive days of work.<br>* Concentration of hexafluoroisopropanol and Sevoflurane are measured in urine by gas chromatography<br>|
| Anaesthesiologists outside the operating room<br>Anaesthesiologists working outside of the operating room, for example pain service or anaesthesiological walk-in clinic | Diagnostic Test: HFIP and Sevoflurane are measured after 3 consecutive days of work.<br>* Concentration of hexafluoroisopropanol and Sevoflurane are measured in urine by gas chromatography<br>|
| Physicians not exposed<br>Physicians not having contact with patients on wards/outpatient clinics after exposure with sevoflurane | Diagnostic Test: HFIP and Sevoflurane are measured after 3 consecutive days of work.<br>* Concentration of hexafluoroisopropanol and Sevoflurane are measured in urine by gas chromatography<br>|
| Patients<br>Patients having undergone sevoflurane anesthesia for elective surgery | Diagnostic Test: HFIP and Sevoflurane are measured after 3 consecutive days of work.<br>* Concentration of hexafluoroisopropanol and Sevoflurane are measured in urine by gas chromatography<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Urinary HFIP concentration (µg/l) | After 3 consecutive days of work a urine sample is collected and urinary HFIP is measured by gas chromatography | After 3 consecutive days of work | 
| Urinary sevoflurane concentration (µg/l) | After 3 consecutive days of work a urine sample is collected and urinary sevoflurane is measured by gas chromatography | After 3 consecutive days of work |