title: Perioperative intravenous lidocaine has preventive effects on postoperative pain and morphine consumption after major abdominal surgery.
abstract: Sodium channel blockers are approved for IV administration in the treatment of neuropathic pain states. Preclinical studies have suggested antihyperalgesic effects on the peripheral and central nervous system. Our objective in this study was to determine the time course of the analgesic and antihyperalgesic mechanisms of perioperative lidocaine administration. Forty patients undergoing major abdominal surgery participated in this randomized and double-blinded study. Twenty patients received lidocaine 2% (bolus injection of 1.5 mg/kg in 10 min followed by an IV infusion of 1.5 mg. kg(-1). h(-1)), and 20 patients received saline placebo. The infusion started 30 min before skin incision and was stopped 1 h after the end of surgery. Lidocaine blood concentrations were measured. Postoperative pain ratings (numeric rating scale of 0-10) and morphine consumption (patient-controlled analgesia) were assessed up to 72 h after surgery. Mean lidocaine levels during surgery were 1.9 +/- 0.7 microg/mL. Patient-controlled analgesia with morphine produced good postoperative analgesia (numeric rating scale at rest, <or=3; 90%-95%; no group differences). Patients who received lidocaine reported less pain during movement and needed less morphine during the first 72 h after surgery (103.1 +/- 72.0 mg versus 159.0 +/- 73.3 mg; Student's t-test; P < 0.05). Because this opioid-sparing effect was most pronounced on the third postoperative day, IV lidocaine may have a true preventive analgesic activity, most likely by preventing the induction of central hyperalgesia in a clinically relevant manner.
  
  
  CONCLUSIONS
  The perioperative administration of systemic small-dose lidocaine reduces pain during surgery associated with the development of pronounced central hyperalgesia, presumably by affecting mechanoinsensitive nociceptors, because these have been linked to the induction of central sensitization and were shown to be particularly sensitive to small-dose lidocaine.
authors.affiliation: *Department of Anesthesiology, University of Erlangen, Erlangen, Germany; †Department of Anesthesiology Mannheim, University of Heidelberg, Mannheim, Germany; and ‡Department of Anesthesiology, St. Marien Hospital Siegen, Siegen, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Koppert
authors.forename: Marc
authors.initials: M
authors.lastname: Weigand
authors.forename: Frank
authors.initials: F
authors.lastname: Neumann
authors.forename: Reinhard
authors.initials: R
authors.lastname: Sittl
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schuettler
authors.forename: Martin
authors.initials: M
authors.lastname: Schmelz
authors.forename: Werner
authors.initials: W
authors.lastname: Hering
mesh_terms: D000005:Abdomen / Q000601:surgery*; D000368:Aged; D016058:Analgesia, Patient-Controlled; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000627:therapeutic use*; D000779:Anesthetics, Local / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage / Q000627:therapeutic use*; D010149:Postoperative Pain / Q000188:drug therapy / Q000517:prevention & control*; D020250:Postoperative Nausea and Vomiting / Q000453:epidemiology; D011446:Prospective Studies; D016019:Survival Analysis
chemical_list: D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D009020:Morphine; D008012:Lidocaine