Comparison of epidural morphine, hydromorphone and fentanyl for postoperative pain control in children undergoing orthopaedic surgery

The safety and side-effects profile of epidural administration of a hydroph ilic (morphine), highly lipophilic (fentanyl) and a drug with intermediate hydrophilic and lipophilic activity (hydromorphone) were compared in 90 chi ldren undergoing orthopaedic procedures. Ninety patients were randomly assi gned (30 in each group) to receive epidural morphine, hydromorphone, or fen tanyl for postoperative analgesia. Respiratory effects, nausea, somnolence, urinary retention, pruritus and visual pain scales were evaluated and comp ared during a 30-h period following surgery. In the morphine group, 25% sho wed respiratory depression with oxygen saturation below 90% but there was n o incidence of respiratory depression in the fentanyl or hydromorphone grou ps. Somnolence was prominent in some of the patients in all the groups, but was more prolonged in the morphine group. Statistically, there was no sign ificant difference in nausea between the groups, but pruritus was more seve re and frequent in the morphine group. The incidence of urinary retention i n the morphine group was higher compared with the fentanyl and hydromorphon e groups. Ln conclusion, epidural hydromorphone, demonstrating less side-ef fects, is preferable to morphine and fentanyl for epidural analgesia in chi ldren.