Accelerated recovery from sevoflurane anesthesia with isocapnic hyperpnoea.

Author(s): Katznelson R, Minkovich L, Friedman Z, Fedorko L, Beattie WS, Fisher JA

Affiliation(s): Department of Anesthesiology, Toronto General Hospital, Eaton North 3-453, 200 Elizabeth St., Toronto, ON M5G 2C4, Canada. rita.katznelson@uhn.on.ca

Publication date & source: 2008-02, Anesth Analg., 106(2):486-91, table of contents.

Publication type: Comparative Study; Randomized Controlled Trial

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). CONCLUSION: IH accelerates recovery from sevoflurane anesthesia and shortens operating room and postanesthetic care unit stay.