High-dose intrathecal diamorphine for analgesia after Caesarean section

Anaesthesia. 2001 Jan;56(1):54-60. doi: 10.1046/j.1365-2044.2001.01763-3.x.


Forty women undergoing elective Caesarean section under spinal anaesthesia using hyperbaric 0.5% bupivacaine were randomly allocated to receive either 0.5 mg or 1 mg intrathecal diamorphine. All women received diclofenac 100 mg at the end of surgery and morphine via a patient-controlled analgesia system. Oral analgesics were not used. Postoperative analgesia was more prolonged and more reliable in the 1-mg group. Mean time to first analgesia was 10.2 h in the 1-mg group and 6.9 h in the 0.5-mg group, and 45% in the 1-mg group used no morphine, compared with 10% in the 0.5-mg group. Mean morphine consumption over 24 h was 5.2 mg in the 1-mg group and 10.6 mg in the 0.5-mg group. Pain scores all tended to be lower in the 1-mg group but this was only significant at 4 h. There were no serious side-effects. Minor side-effects were common but well tolerated, and the incidence did not differ between the groups. If intrathecal diamorphine is used in combination with rectal diclofenac and without oral analgesia, then 1 mg provides superior analgesia to 0.5 mg without any worsening of the side-effects.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Administration, Rectal
  • Adult
  • Analgesia, Obstetrical / methods*
  • Analgesia, Patient-Controlled / statistics & numerical data
  • Analgesics, Opioid / administration & dosage*
  • Anti-Inflammatory Agents, Non-Steroidal / administration & dosage
  • Cesarean Section / methods*
  • Chi-Square Distribution
  • Diclofenac / administration & dosage
  • Dose-Response Relationship, Drug
  • Drug Therapy, Combination
  • Female
  • Heroin / administration & dosage*
  • Humans
  • Injections, Spinal
  • Pain Measurement
  • Pregnancy
  • Statistics, Nonparametric
  • Treatment Outcome


  • Analgesics, Opioid
  • Anti-Inflammatory Agents, Non-Steroidal
  • Diclofenac
  • Heroin