title: Pre-emptive lumbar epidural anaesthesia reduces postoperative pain and patient-controlled morphine consumption after lower abdominal surgery.
abstract: The present study tested the hypothesis that patients receiving epidural bupivacaine before surgery would require less morphine postoperatively and/or report less intense pain than patients receiving epidural bupivacaine after incision but before the end of surgery. Forty-two patients (ASA class I-III) scheduled for lower abdominal surgery were randomly assigned to 1 of 2 groups of equal size and prospectively studied using a double-blind, placebo-controlled crossover design. Epidural catheters were placed in the T12-L1 or L1-L2 interspaces pre-operatively, the position of the catheter was confirmed with 3% chloroprocaine with epinephrine 1:200,000, and sensory testing was carried out until levels had receded to below T12. Group 1 received 15 ml of 0.5% epidural bupivacaine injected 35 min before incision followed by 15 ml of epidural normal saline 30 min after incision. Group 2 received 15 ml of epidural normal saline injected 37 min before incision followed by 15 ml of 0.5% epidural bupivacaine 30 min after incision. General anaesthesia was induced with thiopental (4-6 mg/kg) and maintained with N2O/O2 and isoflurane. Paralysis was achieved with pancuronium (0.1 mg/kg). Opioids were not used as pre-medication or during surgery. Postoperative analgesia consisted of patient-controlled (PCA) intravenous morphine. Visual analogue pain scores (VAS) (at rest and after standardized mobilization) did not differ significantly between the 2 groups but McGill Pain Questionnaire (MPQ) pain ratings were significantly lower in group 1 at the 24 and 72 h assessments. Group 1 used significantly less morphine than did group 2 between 12 and 24 h after surgery.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Psychology, The Toronto Hospital, Toronto, M5G 2C4 OntarioCanada Department of Anaesthesia, The Toronto Hospital, Toronto, M5G 2C4 OntarioCanada Department of Behavioural Science, University of Toronto, Toronto, Ontario M5S 1A8 Canada Department of Anaesthesia, University of Toronto, Toronto, Ontario M5S 1A8 Canada.
authors.forename: Joel
authors.initials: J
authors.lastname: Katz
authors.forename: Michel
authors.initials: M
authors.lastname: Clairoux
authors.forename: Brian P
authors.initials: BP
authors.lastname: Kavanagh
authors.forename: Sandra
authors.initials: S
authors.lastname: Roger
authors.forename: Hilary
authors.initials: H
authors.lastname: Nierenberg
authors.forename: Cormac
authors.initials: C
authors.lastname: Redahan
authors.forename: Alan N
authors.initials: AN
authors.lastname: Sandler
mesh_terms: D000005:Abdomen / Q000601:surgery*; D016058:Analgesia, Patient-Controlled; D000758:Anesthesia; D000767:Anesthesia, Epidural; D001786:Blood Glucose / Q000378:metabolism; D002045:Bupivacaine / Q000627:therapeutic use; D018592:Cross-Over Studies; D004311:Double-Blind Method; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage / Q000627:therapeutic use*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000517:prevention & control*
chemical_list: D001786:Blood Glucose; D009020:Morphine; D006854:Hydrocortisone; D002045:Bupivacaine