(041) Pre-Operative Bilateral Pudendal Nerve Blocks can Reduce Opioid Utilization for Patients Undergoing Urologic Prosthetic Procedures
Authors: Liu B , Campbell J 
Published: February 2024

Abstract

Introduction
Opioid related overdoses and deaths have been increasing in recent decades, and recent studies have shown that even short courses of opioids can result in dependence and misuse. Urologic prosthetic procedures can be painful, and historically pain management has been predominantly through opioid-based analgesia. Multimodal pain management plans have been shown to help reduce exposure to opioids, and these include local nerve blockade.

Objective
Our study aims to assess the efficacy of bilateral pudendal nerve block in post-operative pain management and reduction of opioid use.

Methods
We conducted a retrospective review of all patients undergoing urologic prosthetic surgeries at a single Canadian institution between September 2020 and June 2023. Prosthetic surgeries included inflatable penile prosthesis (IPP) and artificial urethral sphincter (AUS) implants and explantation/reimplantation, but patients were only included once during the study period. Patients with chronic pain or missing pain data were excluded. Patients received bilateral pudendal nerve blocks at the discretion of the surgeon as a practice change starting in 2021 and compared to a control group (no blocks). Pain was assessed by the nursing care team using an analogue rating scale (out of 10), and all opioid and non-opioid pain medications were blindly recorded by nursing as their part of their usual documentation. Opioid utilization was converted to oral morphine equivalents (OMEs). Primary outcome was OMEs utilization in the post-operative period while in hospital, with a secondary of overall pain scores. Data was analysed using two-sample t-tests, and significance set to a p-value of 0.05.

Results
Our study included a total of 134 patients, with 59 patients receiving preoperative bilateral pudendal nerve blocks (54 IPP, 5 AUS), and 75 patients receiving the standard protocol (31 IPP, 44 AUS). The median age of patients receiving pudendal nerve blocks was 62.51 compared to the control group median age of 67.81. (p&lt;0.05). There was no difference in ages in sub-analysis of IPP and AUS cohorts. Sub-analysis of the AUS cohort demonstrated a lower median pain score immediately post-op for those receiving blocks compared to control (0.8 vs. 2.73 respectively, p&lt;0.05), with no difference in pain scores otherwise. AUS patients with pudendal nerve blocks consumed significantly less OMEs on day of surgery (median 0 vs. 6.75 OMEs, p&lt;0.05). The IPP cohort with pudendal nerve blocks had no difference in pain scores compared to control, but consumed significantly less OMEs on day of surgery (9.06 vs. 12.56 OMEs respectively, p&lt;0.05) and on post-operative day one (2.99 vs. 7.30 OMEs respectively, p&lt;0.05).

Conclusions
Preoperative bilateral pudendal nerve blocks appear to reduce post-operative opioid use for patients undergoing urologic prosthetic surgery. Regular use of pudendal nerve blocks for patients undergoing prosthetic and pelvic surgeries may be an efficient means to reduce patient exposure to opioids. Bilateral pudendal nerve blockade for all genital and pelvic surgeries may be an effective opioid harm reduction strategy and warrants further investigation and patient satisfaction outcomes.

Disclosure
No.