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Background: Leaks occur often throughout the process of delivering inhaled anesthesia prior to and during surgery. Leaks typically occur around the patient’s mouth, nose, and eyes. Potent inhaled anesthetics (PIAs) include halothane, sevoflurane, desflurane, and isoflurane. All PIAs, to one degree or another, pose hazards to human health. PIAs are associated with reproductive toxicity, spontaneous miscarriages in pregnant persons as well as an increased risk of congenital abnormalities in offspring. In other words, PIAs are thought to be both abortifacients as well as teratogens. PIAs are also associated with hepatotoxicity, neurotoxicity, cognitive impairment, as well as increased incidence of malignancy.

Methods: Preliminary interviews with stakeholders were conducted to assess the desirability, viability, and utility of a product to trap and remove waste anesthetic gas (WAG) from the perifacial region before it diffuses into the ambient air. We used wearable detector badges (similar to a dosimeter) from Assay Technology Inc. for qualitative measurements of WAG levels in several operating rooms. We used low-fidelity mockups for early prototyping, FDM and SLA 3D printing techniques, and urethane casts for high-fidelity working prototypes. We also performed real-time simulations using a visible aerosol agent in order to record and study the efficacy of our device.

Results: We found dramatically elevated levels of sevoflurane in the operating room, with our highest readings at ~10x NIOSH permissible exposure limits. With our visual simulation we saw a markedly reduced flow of WAG into the surrounding air.

Conclusions: Our device adequately addresses a significant and unaddressed issue in healthcare and shows viability from an economic standpoint as well. We are currently designing a study to further evaluate levels of WAG and exploring potential studies with live anesthetic agents.