Development of a prototype anti-pollution filter for volatile anesthetics

Area of Science:

• Anesthesiology
• Environmental Health
• Biomedical Engineering

Background:

• Volatile anesthetic agents in cardiopulmonary bypass (CPB) enable "single drug anesthesia" and lower postoperative troponin.
• Connecting exhaust systems to the oxygenator's gas outlet prevents operating room pollution.
• Atmospheric pollution by volatile agents during CPB remains a concern.

Purpose of the Study:

• To design and test a prototype filter for volatile anesthetic agents.
• To evaluate the filter's adsorption efficacy during simulated CPB.
• To prevent both operating room and environmental pollution.

Main Methods:

• Bench tests were conducted to design a prototype filter, ensuring no damage to membrane oxygenators.
• Tests included adsorption efficacy, filter dimensions, flow-pressure curves, sizing, and tightness.
• Calgon AT 410 activated charcoal granules were selected for their adsorption properties.

Main Results:

• The prototype filter effectively adsorbed isoflurane (100 min), sevoflurane (95 min), and desflurane (95 min).
• A filter chamber of 30-cm width and 10-cm diameter with 200g of Calgon AT410 was sufficient for 90 min of sevoflurane adsorption.
• The filter design prevented damage to membrane oxygenators during ex-vivo testing.

Conclusions:

• The prototype filter successfully adsorbed significant amounts of volatile anesthetic agents during simulated CPB.
• This filter offers a potential solution for reducing environmental contamination from anesthetic gases.
• Further development could lead to widespread use in CPB procedures.