1406 DOUBLE BLINDED RANDOMIZED PLACEBO CONTROLLED TRIAL TO DETERMINE EFFECT OF BUPIVACAINE DORSAL PENILE BLOCK ON POSTOPERATIVE PAIN AND FOLEY DISCOMFORT FOLLOWING ROBOTIC ASSISTED RADICAL PROSTATECTOMY

Abstract

INTRODUCTION AND OBJECTIVES: Urethral catheterization is a source of significant discomfort and pain after Robotic Assisted Radical Prostatectomy (RARP). Herein we present an interim analysis of a study assessing the effect of Bupivacaine dorsal penile block on postoperative pain after RARP. METHODS: Between December 2011 and October 2012 at total of 78 patients were enrolled in a prospective double blinded randomized placebo controlled study comparing bupivacaine (20cc at 0.5%) dorsal penile block injection versus normal saline injection at the conclusion of RARP. Postoperative pain and urinary symptoms were evaluated using questionnaires based on visual analog scales at multiple time points until Foley removal. In addition, patients were required to maintain a log of narcotic and pain medication use after RARP until Foley catheter removal. Student?s t test and Fisher?s exact tests were used for continuous parametric and categorical data, respectively, with p 0.05 considered to be significant. RESULTS: No complications or adverse events occurred in this study. There was no difference with respect to age, pre-operative PSA, stage, Gleason score, body mass index, operative time or history of diabetes between the two groups. There was a trend toward less inpatient narcotic use in patients receiving block vs. placebo (3.9 mg vs. 5.7 mg morphine equivalents, p .19). Outpatient narcotic use was similarly less in the patients receiving block vs. placebo (13.8 mg vs. 15mg morphine equivalents, p .77). With respect to abdominal incisional pain and bladder spasm discomfort, there was no significant difference at the 18 hour time point (average discharge time) or at the end of the follow up period on day 9. At the 18 hour time point period patients receiving penile block reported significantly less penile pain than patients receiving saline injection (1.39 vs. 2.0, p .04). At the end of the follow up period this difference remained significant in favor of penile block (.75 vs. 3.27, p .04). CONCLUSIONS: In this interim analysis, penile block with bupivacaine appears to improve penile pain score postoperatively after RARP. These results suggest that initial post-operative pain management may affect the perception of pain going forward. Further confirmation is needed to standardize penile block as a viable protocol to manage post-operative Foley discomfort after RARP.