Ronald S. Litman, D.O.; Girish P. Joshi, M.B.B.S., M.D., F.F.A.R.C.S.I. Anesthesiology 2014
"Therefore, we recommend the use of specially designed charcoal filters (Vapor-Clean; Dynasthetics, Salt Lake City, UT) which easily insert into the proximal ends of the inspiratory and expiratory limbs of the anesthetic circuit.10 These filters will rapidly capture residual amounts of anesthetic gas remaining in the anesthesia circuit as long as the agent vaporizer is turned off (if the vaporizer is turned on, the filters can be easily saturated and anesthetic gas will reach the patient). This process can be accomplished in the several minutes that it takes to change over the machine between patients."
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