INTRAVESICAL MORPHINE ANALGESIA AFTER BLADDER SURGERY

Purpose: A recent demonstration of peripheral opioid receptors suggest ed the possibility of delivering morphine locally into the bladder aft er reimplantation for ameliorating the discomfort of postoperative bla dder irritation with spasms. Since we do not use bladder drainage afte r reimplantation, dripping a morphine solution into the bladder permit s contact with the urothelium between voidings. A pilot trial using an arbitrary concentration was subjectively beneficial for treating thes e patients postoperatively. We now report a prospective randomized stu dy evaluating the effectiveness and dosage of various concentrations o f intravesical morphine infusions. Materials and Methods: A total of 5 2 children undergoing ureteral reimplantation was randomized to receiv e 1 of 3 concentrations of intravesical morphine (0.05, 0.375 or 0.5 m g./ml.). A small feeding tube remained in the bladder to drip a contin uous infusion postoperatively, Subsequent postoperative pain was treat ed with meperidine, acetaminophen and codeine, and/or a belladonna and opium suppository. During each shift a nurse assisted the child in as sessing pain using a Baker-Wong faces scale. Bladder infusion was disc ontinued after day 3 postoperatively and plasma morphine levels were m easured on the first morning postoperatively. Kruskal-Wallis and paire d t tests were used to evaluate significance. Results: Patients report ed greater pain in the group infused with 0.05 mg./ml. on 4 of 6 shift s on the first 2 days postoperatively. No difference was noted on post operative day 3, Plasma morphine was undetectable by high pressure liq uid chromatography. Conclusions: This study offers objective evidence that bladder morphine infusion is effective for ameliorating postopera tive pain in the first 48 hours after intravesical ureteral reimplanta tion. The dose given today is 0.5 mg./ml. delivered at 0.04 ml./kg. pe r hour.