Dynamic changes in blood solubility of desflurane, isoflurane, and halothane during cardiac surgery.
OBJECTIVE
To determine an estimate of blood/gas partition coefficients of volatile anesthetics during cardiac surgery.


METHODS
Descriptive


METHODS
University hospital


METHODS
Six adult patients undergoing valvular replacement with hypothermic cardiopulmonary bypass.


RESULTS
Blood samples were obtained from patients at 6 time points: before induction, at skin incision, at aortic cannulation, at rewarming during bypass, at weaning off bypass, and at skin suture. Measured blood/gas partition coefficients were plotted against corresponding solubilities estimated according to the combined effects of hypothermia and hemodilution. Significant differences were found in blood/gas partition coefficients of the 3 anesthetics at different times during surgery (p < 0.05). Blood/gas partition coefficients at weaning off bypass were the lowest, about 75% of that before anesthetic induction. A direct linear relationship for estimated solubility against measured solubility was found (r2 = 0.94; p < 0.05).


CONCLUSIONS
Dynamic changes in blood/gas partition coefficients of volatile anesthetics were found during cardiac surgery. They could be estimated by using multiple linear regression equations reflecting the combined effects of hypothermia and hemodilution.
Zhou
J X
JX
Department of Anesthesiology, Fuwai Hospital and Cardiovascular Institute, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, P. R. China. jianxinz@yeah.net
Liu
J
J
D000328:Adult; D018685:Anesthetics, Inhalation / Q000097:blood*; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D000077335:Desflurane; D006221:Halothane / Q000097:blood* / Q000737:chemistry; D006438:Hemodilution; D006801:Humans; D007530:Isoflurane / Q000031:analogs & derivatives / Q000097:blood* / Q000737:chemistry; D008297:Male; D012995:Solubility
D018685:Anesthetics, Inhalation; D000077335:Desflurane; D007530:Isoflurane; D006221:Halothane