Effects of continuous epidural administration of fentanyl and morphine on postcesarean pain

We studied the effects of continuous epidural administration of fentanyl and morphine with bupivacaine for management of postcesarean pain. Eighteen patients received either bolus epidural administration of fentanyl 100 micrograms or morphine 3 mg with 0.5% bupivacaine 4 ml, followed by continuous infusion of fentanyl 33 micrograms.ml-1 with 0.17% bupivacaine or morphine 0.21 mg.ml-1 with 0.17% bupivacaine for 48 hours, respectively. Pain score was assessed at 0 h, 12h, 24h and 48h after leaving the operating room. Pain score increased significantly and progressively in the fentanyl group. In all cases pruritus was noted. Severe pruritus was observed in the morphine group significantly more than in the fentanyl group. The current results indicate that morphine may be preferable to fentanyl for postcesarean pain control using the present opioid doses.