Postoperative extradural analgesia in children: comparison of morphine with fentanyl †

Abstract

We have compared the efficacy and side effects of extradural morphine with extradural fentanyl for postoperative pain relief. Thirty children (ages 1-16 yr) were allocated randomly to receive, after extradural administration of 0.5% bupivacaine 0.75 ml kg-1 and before surgical incision, extradural morphine 0.75 microgram kg-1 (group M), with an additional dose administered 24 h later or extradural fentanyl 2 micrograms kg-1 (group F) followed by a continuous extradural infusion (during 48 h). There was no major complication (respiratory depression). Pain scores were satisfactory in both groups for 48 h. Ventilatory frequency was greater in group M 20, 21, 22, 23 and 25 h after the beginning of analgesia (P < 0.05). Pruritus, nausea and vomiting were less common with extradural fentanyl (20% vs 53%, P < 0.05 and 0% vs 33%, P < 0.05) than with morphine. Urinary retention occurred with equal frequency (25%) in the two groups. After a bolus of 2 micrograms kg-1, continuous extradural infusion of fentanyl 5 micrograms kg-1 day-1 provided analgesia comparable to that from a daily bolus of extradural morphine 0.75 mg kg-1 and produced fewer side effects.

Current management of pediatric postoperative pain

“…The incidence of nausea and vomiting with morphine, buprenorphine and tramadol (Ultram ® , Johnson & Johnson, PA, USA) is often reported to be high because up to 50% of children may develop emesis [61][62][63][64]. Nausea and vomiting may occur significantly less often with fentanyl and sufentanil (Sufenta ® , Wyeth-Ayerst Laboratories, PA, USA) [38,47,[65][66][67].…”

“…Morphine doses above 0.1 mg/kg are associated with a greater than 50% incidence of vomiting [61,63]. With fentanyl at doses of 2 µg/kg or less, vomiting occurs very rarely [38,65,66]. In contrast to dose-dependency, the risk of nausea and vomiting appears not to vary between different administration routes [64].…”

Epidural and subarachnoid blockade in children

“…Opioids have been used alone by intermittent injection and continuous infusion to provide epidural analgesia in children [114] but are more commonly added to local anaesthetic solutions for epidural use to improve analgesia, minimise the doses of each analgesic required, reduce the incidence of sideeffects and to provide a degree of sedation. Fentanyl is a ............................................................................................................................................................................................................................................ .h À1 by infusion [61,90].…”

A qualitative systematic review of morphine treatment in children with postoperative pain

“…Postoperative pain intensity was evaluated in 12 of the 14 comparisons (37,41,44,46,47,51,53,58,59,63). The pain scores or percentage of patients in pain were significantly reduced after single doses of morphine 30 μg·kg −1 preoperatively or 75 μg·kg −1 postoperatively (46,63) compared with no intervention used as control and after a constant epidural infusion of morphine 4 μg·kg −1 ·h −1 with clonidine as control (41).…”