title: Dextromethorphan reduces immediate and late postoperative analgesic requirements and improves patients' subjective scorings after epidural lidocaine and general anesthesia.
abstract: Central N-methyl-D-aspartate receptors modulate postoperative pain. We compared the effects of preincision oral dextromethorphan (DM), an N-methyl-D-aspartate receptor antagonist, on postoperative IV patient-controlled analgesia morphine demand and on subjective variables in 80 patients undergoing lower-body procedures who were randomly assigned to epidural lidocaine (LA; 16 mL, 1.6%) or general anesthesia (GA). The patients were premedicated 90 min before surgery with placebo or DM 90 mg (20 patients per group) in a double-blinded manner. Postoperative IV patient-controlled analgesia morphine administration started when subjective pain intensity was > or =4 of 10 (visual analog scale) and lasted 2 h. Observation continued up to 3 days, during which patients could use diclofenac. LA-DM and GA-DM patients required 45%-50% less morphine and diclofenac compared with their placebo counterparts (P < 0.001). However, GA-DM patients made twice as many attempts to self-administer morphine as LA-DM patients (P = 0.005). Eight LA-DM versus two GA-DM patients (P < 0.01) used no morphine or diclofenac. All DM patients experienced significantly (P < 0.001) less pain, were less sedated, and felt better than their placebo counterparts; however, compared with placebo, DM improved subjective scorings in the GA patients more significantly (P < 0.05) than in the LA patients. We conclude that oral DM 90 mg in patients undergoing surgery under LA or GA reduces morphine and diclofenac use by approximately 50% in the immediate and late postoperative period compared with placebo. Subjectively scored levels of pain, sedation, and well-being were better as well.
authors.affiliation: Post-Anesthesia Care Unit, Tel Aviv Sourasky Medical Center, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Avi A
authors.initials: AA
authors.lastname: Weinbroum
mesh_terms: D000368:Aged; D016058:Analgesia, Patient-Controlled; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000627:therapeutic use; D000767:Anesthesia, Epidural; D000768:Anesthesia, General; D000779:Anesthetics, Local; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000627:therapeutic use; D001182:Arthroscopy; D003915:Dextromethorphan / Q000627:therapeutic use*; D004008:Diclofenac / Q000008:administration & dosage / Q000627:therapeutic use; D004311:Double-Blind Method; D005260:Female; D006552:Hernia, Inguinal / Q000601:surgery; D006801:Humans; D008012:Lidocaine; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage / Q000627:therapeutic use; D010147:Pain Measurement / Q000187:drug effects; D010149:Postoperative Pain / Q000188:drug therapy*; D017060:Patient Satisfaction; D011229:Preanesthetic Medication
chemical_list: D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D000894:Anti-Inflammatory Agents, Non-Steroidal; D004008:Diclofenac; D003915:Dextromethorphan; D009020:Morphine; D008012:Lidocaine