Intrathecal fentanyl-induced pruritus during labour: the effect of prophylactic ondansetron.
Fentanyl is commonly used for spinal analgesia during labour but it is associated with a high incidence of pruritus. This randomised, double-blind, placebo-controlled study was performed to evaluate the effect of prophylactic ondansetron on the incidence and severity of pruritus among parturients receiving intrathecal fentanyl as part of combined spinal-epidural analgesia. Seventy-three women were randomised to receive either saline placebo (group P, n = 25), ondansetron 4 mg (group O4, n = 23) or ondansetron 8 mg (group O8, n = 25) intravenously before intrathecal fentanyl 25 micrograms and bupivacaine 2 mg. The incidence and severity of pruritus were measured using a verbal rating and a visual analogue scale, and by the requirement for rescue anti-pruritic medication (naloxone). The overall incidence of pruritus was 95% (group P 100%, group O4 95%, group O8 90%). There were no significant differences between groups for severity of pruritus or requirement for treatment (naloxone given to 45%, 28% and 35% of groups P, O4 and O8 respectively). Secondary outcomes such as the incidence of headache, pain and nausea were not significantly different between groups. We conclude that prophylactic ondansetron 4 or 8 mg intravenously was ineffective in reducing the incidence or severity of intrathecal fentanyl-induced pruritus during labour.
Wells
J
J
Department of Anaesthesia, Fremantle Hospital, Fremantle, Australia. jason.wells@health.wa.gov.au
Paech
M J
MJ
Evans
S F
SF
D000328:Adult; D016362:Analgesia, Obstetrical / Q000009:adverse effects*; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000009:adverse effects*; D004311:Double-Blind Method; D005260:Female; D005283:Fentanyl / Q000008:administration & dosage / Q000009:adverse effects*; D006801:Humans; D007275:Injections, Intravenous; D007278:Injections, Spinal; D009270:Naloxone / Q000627:therapeutic use; D009292:Narcotic Antagonists / Q000627:therapeutic use; D017294:Ondansetron / Q000008:administration & dosage / Q000627:therapeutic use*; D010146:Pain / Q000453:epidemiology / Q000517:prevention & control; D020250:Postoperative Nausea and Vomiting / Q000453:epidemiology / Q000517:prevention & control; D011247:Pregnancy; D011537:Pruritus / Q000139:chemically induced* / Q000453:epidemiology / Q000517:prevention & control*; D012702:Serotonin Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*
D000701:Analgesics, Opioid; D009292:Narcotic Antagonists; D012702:Serotonin Antagonists; D009270:Naloxone; D017294:Ondansetron; D005283:Fentanyl