A Single Dose of Intrathecal Morphine Without Local Anesthetic Provides Long-Lasting Postoperative Analgesia After Radical Prostatectomy and Nephrectomy
Abstract
PURPOSE: Pain after open urological procedures is often intense. The aim of the study was to compare the efficacy of intrathecal morphine with systemic analgesia approaches.
DESIGN: Prospective, randomized, single-blind controlled study. METHODS: Patients undergoing open prostatectomy or nephrectomy were randomly divided into the intervention group or the control group.
Patients in the intervention group received morphine 250 mcg in 2.5 mL saline intrathecally. Anesthesia was identical in both groups.
All patients were admitted to the intensive care unit (ICU) postoperative and received paracetamol 1 g intravenously every 6 hours and diclofenac 75 mg intramuscularly every 12 hours. If postoperative pain exceeded four on the numeric rating scale, morphine 10 mg was administered subcutaneously.
Pain intensity, time to first dose of morphine, morphine doses, and side effects were recorded. FINDINGS: In total, 41 patients were assigned to the intervention group and 57 to the control group.
The time to administration of the first dose of morphine was significantly (P < .001) longer in the intervention group when compared to controls. This observation was also noted individually for patients undergoing nephrectomy (36.86 hours vs 4.06 hours) and prostatectomy (33.13 hours vs 4.5 hours).
Many patients did not need opioids after surgery in the intervention group (nephrectomy 72% vs 3%, prostatectomy 75% vs 4.5%, P < .001). There was no significant difference in the incidence of side effects.
CONCLUSIONS: The results of our study confirmed that preoperative intrathecal morphine provides long-lasting analgesia and reduces the need for postoperative systemic administration of opioids. Adverse effects are minor and comparable between groups.