Intrathecal fentanyl-induced pruritus during labour: the effect of prophylactic ondansetron

• Published in: International journal of obstetric anesthesia Vol. 13; no. 1; pp. 35 - 39
• Main Authors: Wells, J, Paech, M.J, Evans, S.F
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.01.2004
• Subjects: Adult; Analgesia, Obstetrical - adverse effects; Analgesics, Opioid - administration & dosage; Analgesics, Opioid - adverse effects; Double-Blind Method; Female; Fentanyl - administration & dosage; Fentanyl - adverse effects; Humans; Injections, Intravenous; Injections, Spinal; Naloxone - therapeutic use; Narcotic Antagonists - therapeutic use; Ondansetron - administration & dosage; Ondansetron - therapeutic use; Pain - epidemiology; Pain - prevention & control; Postoperative Nausea and Vomiting - epidemiology; Postoperative Nausea and Vomiting - prevention & control; Pregnancy; Pruritus - chemically induced; Pruritus - epidemiology; Pruritus - prevention & control; Serotonin Antagonists - administration & dosage; Serotonin Antagonists - therapeutic use
• ISSN: 0959-289X; 1532-3374
• DOI: 10.1016/j.ijoa.2003.07.001

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 μg 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.