title: The timing of acupuncture stimulation does not influence anesthetic requirement.
abstract: Studies suggest that acupuncture is more effective when induced before the induction of general anesthesia than afterwards. We tested the hypothesis that electro-acupuncture initiated 30 min before the induction reduces anesthetic requirement more than acupuncture initiated after the induction. Seven volunteers were each anesthetized with desflurane on 3 study days. Needles were inserted percutaneously at four acupuncture points thought to produce analgesia in the upper abdominal area and provide generalized sedative and analgesic effects: Zusanli (St36), Sanyinjiao (Sp6), Liangqiu (Sp34), and Hegu (LI4). Needles were stimulated at 2 Hz and 10 Hz, with frequencies alternating at 2-s intervals. On Preinduction day, electro-acupuncture was started 30 min before the induction of anesthesia and maintained throughout the study. On At-induction day, needles were positioned before the induction of anesthesia, but electro-acupuncture stimulation was not initiated until after the induction. On Control day, electrodes were positioned near the acupoints, but needles were not inserted. Noxious electrical stimulation was administered via 25-gauge needles on the upper abdomen (70 mA; 100 Hz; 10 s). The desflurane concentration was increased 0.5% when movement occurred and decreased 0.5% when it did not. These up-and-down sequences continued until volunteers crossed from movement to no movement four times. The P(50) of logistic regression identified desflurane requirement. Desflurane requirement was similar on the Control (mean +/- sd; 5.2% +/- 0.6%), Preinduction (5.0% +/- 0.8%), and At-induction (4.7% +/- 0.3%; P = 0.125) days. This type of acupuncture is thus unlikely to facilitate general anesthesia or decrease the requirement for anesthetic drugs.
authors.affiliation: *Department of Anesthesiology and Perioperative Medicine and †Outcomes Research™ Institute, University of Louisville, Kentucky.
authors.forename: Grigory
authors.initials: G
authors.lastname: Chernyak
authors.forename: Papiya
authors.initials: P
authors.lastname: Sengupta
authors.forename: Rainer
authors.initials: R
authors.lastname: Lenhardt
authors.forename: Edwin
authors.initials: E
authors.lastname: Liem
authors.forename: Anthony G
authors.initials: AG
authors.lastname: Doufas
authors.forename: Daniel I
authors.initials: DI
authors.lastname: Sessler
authors.forename: Ozan
authors.initials: O
authors.lastname: Akça
mesh_terms: D000293:Adolescent; D000328:Adult; D000769:Anesthesia, Inhalation; D000777:Anesthetics / Q000008:administration & dosage*; D018685:Anesthetics, Inhalation; D001831:Body Temperature / Q000187:drug effects; D000077335:Desflurane; D015671:Electroacupuncture; D004569:Electroencephalography / Q000187:drug effects; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007530:Isoflurane / Q000031:analogs & derivatives*; D008297:Male; D013997:Time Factors
chemical_list: D000777:Anesthetics; D018685:Anesthetics, Inhalation; D000077335:Desflurane; D007530:Isoflurane