Accelerated recovery from sevoflurane anesthesia with isocapnic hyperpnoea.
BACKGROUND
Isocapnic hyperpnoea (IH) reduces recovery time from isoflurane anesthesia in animals and humans. We studied the effect of IH on the emergence profile of sevoflurane-anesthetized patients by comparing postoperative recovery variables in patients administered IH (IH group) to those recovered in the customary fashion (control group).


METHODS
We enrolled 30 ASA I-III patients undergoing elective gynecological surgery. Induction and maintenance of anesthesia were standardized with a protocol consisting of fentanyl, propofol, rocuronium, and sevoflurane in air/O2. Patients were randomly assigned to control (C) or IH groups at the end of the surgery. We recorded time intervals from discontinuing sevoflurane to recovery milestones.


RESULTS
Time to tracheal extubation was much shorter in the IH group compared with group C (6.2 +/- 2.1 vs 12.3 +/- 3.8 min, respectively, P < 0.01). The IH group also had shorter times to initiation of spontaneous ventilation (4.2 +/- 1.7 vs 6.5 +/- 3.8 min, P = 0.047), eye opening (5.5 +/- 1.4 vs 13.3 +/- 4.4 min, P < 0.01), bispectral index value >75 (3.9 +/- 1.1 vs 8.8 +/- 3.7 min, P < 0.01), leaving operating room (7.7 +/- 2.0 vs 15.3 +/- 3.4 min, P < 0.01), and eligibility for postanesthetic care unit discharge (67.2 +/- 19.3 vs 90.6 +/- 20.0 min, P < 0.01).


CONCLUSIONS
IH accelerates recovery from sevoflurane anesthesia and shortens operating room and postanesthetic care unit stay.
Katznelson
Rita
R
Department of Anesthesiology, Toronto General Hospital, Eaton North 3-453, 200 Elizabeth St., Toronto, ON M5G 2C4, Canada. rita.katznelson@uhn.on.ca
Minkovich
Leonid
L
Friedman
Zeev
Z
Fedorko
Ludvik
L
Beattie
W Scott
WS
Fisher
Joseph A
JA
D000328:Adult; D000762:Anesthesia Recovery Period; D000769:Anesthesia, Inhalation / Q000295:instrumentation / Q000379:methods*; D002245:Carbon Dioxide / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008738:Methyl Ethers / Q000008:administration & dosage*; D008875:Middle Aged; D010100:Oxygen / Q000008:administration & dosage; D012121:Respiration, Artificial / Q000295:instrumentation / Q000379:methods*; D012189:Retrospective Studies; D000077149:Sevoflurane; D013997:Time Factors
D008738:Methyl Ethers; D002245:Carbon Dioxide; D000077149:Sevoflurane; D010100:Oxygen