title: Naloxone versus nalbuphine infusion for prophylaxis of epidural morphine-induced pruritus.
abstract: This randomized, double-blind study compared the efficacy of two mu-receptor antagonists, naloxone and nalbuphine, in the prophylactic management of pruritus in postcesarean section patients receiving epidural morphine. Dosages of study drugs were individualized by the use of a patient self-administration (PSA) device. All 51 patients were healthy women who received a uniform epidural anesthetic and epidural morphine (5 mg). Coded solutions were infused for 24 h, with 5-min PSA lockout times: Group A (n = 17), nalbuphine 2.5 mg/h, PSA nalbuphine 1 mg; Group B (n = 16), naloxone 50 micrograms/hr, PSA saline; Group C (n = 18), naloxone 50 micrograms/h, PSA naloxone 40 micrograms. Patients were assessed for pruritus and pain every 8 h for 24 h. Both naloxone and nalbuphine provided good relief for pruritus; median pain and pruritus scores were in the none-to-mild range (0-3) for all groups at all assessment intervals. The pruritus scores of the PSA saline group were higher during the 16- to 24-h period (P < 0.05) than the scores of either group receiving A-receptor antagonist by PSA. There was evidence of shortening of the duration of analgesia in patients receiving naloxone who required treatment for pruritus after 16 h. Patients who self-administered large doses of nalbuphine over the first 8 h also reported pain scores consistent with reversal of analgesia. The potency ratio for naloxone:nalbuphine for antagonism of the pruritic effects of epidural morphine was approximately 40:1. Intervention to treat either unrelieved pruritus or pain, respectively, was necessary in the following numbers of patients: Group A, 0/1; Group B, 1/1; Group C, 2/2. Prophylactic infusions offer the potential for labor cost savings by minimizing the need for episodic therapeutic interventions to treat pruritus.
authors.affiliation: Department of Anesthesiology, University of Virginia Health Sciences Center, Charlottesville, VA 22908, USA.
authors.forename: W D
authors.initials: WD
authors.lastname: Kendrick
authors.forename: A M
authors.initials: AM
authors.lastname: Woods
authors.forename: M Y
authors.initials: MY
authors.lastname: Daly
authors.forename: R F
authors.initials: RF
authors.lastname: Birch
authors.forename: C
authors.initials: C
authors.lastname: DiFazio
mesh_terms: D015360:Analgesia, Epidural / Q000009:adverse effects*; D016362:Analgesia, Obstetrical / Q000009:adverse effects*; D016058:Analgesia, Patient-Controlled / Q000295:instrumentation; D000701:Analgesics, Opioid / Q000009:adverse effects*; D002585:Cesarean Section; D017046:Cost Savings; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D016014:Linear Models; D009020:Morphine / Q000009:adverse effects*; D009266:Nalbuphine / Q000627:therapeutic use*; D009270:Naloxone / Q000627:therapeutic use*; D009292:Narcotic Antagonists / Q000627:therapeutic use*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000517:prevention & control; D011247:Pregnancy; D011537:Pruritus / Q000191:economics / Q000517:prevention & control*; D017450:Receptors, Opioid, mu / Q000037:antagonists & inhibitors
chemical_list: D000701:Analgesics, Opioid; D009292:Narcotic Antagonists; D017450:Receptors, Opioid, mu; D009270:Naloxone; D009020:Morphine; D009266:Nalbuphine