Premium
Sevoflurane degradation by soda lime in a circle breathing system
Author(s) -
MUNDAY I. T.,
WARD P. M.,
FODEN N. D.,
JONES R. M.,
KENNA J. G.
Publication year - 1996
Publication title -
anaesthesia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.839
H-Index - 117
eISSN - 1365-2044
pISSN - 0003-2409
DOI - 10.1111/j.1365-2044.1996.tb07842.x
Subject(s) - sevoflurane , soda lime , medicine , anesthesia , ventilation (architecture) , lime , ether , chromatography , zoology , chemistry , meteorology , physics , materials science , organic chemistry , metallurgy , biology
Summary Sevoflurane is degraded by soda lime to a vinyl ether commonly referred to as compound A. We measured the concentration of compound A in the circle breathing system of 31 patients receiving sevoflurane anaesthesia. fnspiratory and expiratory gas samples were analysed using gas chromatography and flame ionisation detection. The end‐tidal sevoflurane concentration and soda lime temperature were recorded. The peak compound A concentration ranged between 10 to 32ppm in the inspiratory limb and 7 to 26 ppm in the expiratory limb. There was a positive correlation between the peak compound A concentration and the end‐tidal sevoflurane concentration (r 2 = 0.545, p < 0.0001) and the soda lime temperature (r 2 = 0.301, p = 0.0014). We conclude that the end‐tidal concentration of sevoflurane and the temperature of the soda lime are important variables in determining concentration of compound A in a circle system.