Reduction of Anesthesiologists' Sevoflurane Exposure During Pediatric Mask Induction With an Additional Scavenger: A Randomized Study

BACKGROUND: Pediatric inhalational induction with a face mask is a well-recognized source of occupational exposure to waste anesthetic gases. Conventional anesthesia machine scavenging systems are ineffective in capturing extra-circuit leaks occurring at the patient-mask interface. Urinary hexafluoroisopropanol (HFIP), a metabolite of sevoflurane, is a sensitive biomarker of systemic exposure. METHODS: In this prospective randomized parallel-group study, 20 anesthesiologists performing pediatric mask inductions with sevoflurane in an induction anesthesia room were allocated to work either with or without an additional external active gas scavenger positioned near the patient's face. Urine samples were collected before exposure and the following morning. HFIP concentrations were quantified by chromatography and normalized to creatinine. Between-group comparisons were performed using Welch's t-test, with a Mann-Whitney U test used as a sensitivity analysis. RESULTS: Urinary HFIP concentrations were significantly higher in anesthesiologists working without the additional scavenger compared with those using the scavenging system (mean ± SD: 0.63 ± 0.30 vs. 0.02 ± 0.04 μg/mL; p = 0.002; Cohen's d = 3.19). HFIP was undetectable or near the analytical detection limit in most samples obtained with scavenging. The observed difference corresponded to a very large effect size, indicating a marked reduction in systemic sevoflurane exposure when the additional scavenger was used. CONCLUSIONS: Use of an additional external scavenging system during pediatric mask induction was associated with a substantial reduction in anesthesiologists' biological exposure to sevoflurane, as assessed by urinary HFIP. These findings provide biological evidence supporting exposure reduction strategies during pediatric inhalational anesthesia, although the clinical significance of the observed differences remains to be established. TRIAL REGISTRATION: ClinicalTrials.gov: NCT06487169.