Black particles in a breathing system are the kind of finding that makes every anesthesia professional stop and look twice. We’re sharing what a large health system uncovered after concerns for mold and moisture accumulation surfaced inside certain GE Healthcare anesthesia workstations used in operating rooms, especially during longer cases and in humid conditions. What started with a routine inspection quickly scaled into a broad audit of OR ventilators, a review of internal moisture points, and an urgent push for real-world mitigation.

We walk through what the investigation found, what cultures grew, and the question everyone asks first: what is the risk to patients? We discuss why the available evidence suggests the infectious risk is likely minimal when high-quality heat and moisture exchange (HME) filtration and breathing circuit filters are used correctly, and why the team still pulled affected machines from service for sterilization per manufacturer instructions. Patient safety isn’t only about infection, though, and we also cover how excess condensate can affect flow sensors and tidal volume accuracy.

Then we get concrete about prevention. We break down where moisture comes from inside an anesthesia ventilator, how low-flow anesthesia and rebreathing can increase water production in the circuit, and why simply turning up fresh gas flow isn’t the right fix when cost and environmental impact matter. You’ll hear the day-to-day moisture mitigation strategies that were implemented, including education, routine moisture and mold checks, overnight handling of circuits and sensors, and why add-on condenser drainage may be necessary for older compatible models.

If you want a practical checklist mindset for anesthesia workstation maintenance, OR ventilator safety, and moisture management, this is for you. Subscribe, share with your colleagues, and leave a review so more teams can spot problems early and keep patients safe.

For show notes & transcript, visit our episode page at apsf.org: https://www.apsf.org/podcast/309-mold-risk-in-anesthesia-workstations/

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