Introduction: Inflatable penile prosthesis (IPP) surgery is the gold standard treatment for medication-refractory erectile dysfunction. While highly satisfactory, post-operative pain and narcotic requirement remains a concern. Use of intraoperative dorsal penile nerve block with long acting local anesthetic can improve postoperative analgesia. Recent studies in non-urologic fields have demonstrated prolonged analgesia with minimal adverse effects with local nerve blocks containing long acting local anesthetic with either dexamethasone or dexmedetomidine. This study aims to evaluate the analgesic efficacy of these adjuvants in bupivacaine penile nerve block as compared to a bupivacaine-only block during primary IPP surgery. Methods: This is a retrospective single institution IRB-approved comparative study of patients undergoing primary IPP placement receiving intraoperative dorsal penile nerve block with either 0.25% bupivacaine (2019) versus combination block with 0.25% bupivacaine + 70 µg dexmedetomidine + 4 mg dexamethasone (2020 - 2021). The primary outcome was pain during the first 24 hours post-operatively (0, 2, 6, 12, 18, and 24 hrs) while secondary outcomes were intra- and postoperative narcotic use, intraoperative hypotension defined here as MAP < 60 for more than 5 minutes or requiring intervention, and intraoperative bradycardia defined here as HR < 50 for more than a minute. Results: Of 98 the patients included, 32 received bupivacaine only and 66 received the combination block. Mean PACU pain in the first 24 hours at all times (0, 2, 6, 12, 18, 24 hrs) were significantly lower in the combination block group (1.1 vs 3.8, 1.6 vs 3.9, 3.1 vs 4.9, 2.4 vs 4.3, 2.9 vs 5.3, 2.3 vs 4.4; p<0.05). Mean total postoperative narcotics was lower for the combination block (46 vs 65, P<0.05). There was no significant difference in intraoperative narcotics between groups (111 vs 132; P=0.133). Of patients who received the combination block, 4 had intraoperative hypotension of MAP <60 for more than 5 minutes and 114 had bradycardia below 50 but did not require intervention. Conclusions: Intraoperative dorsal penile nerve block consisting of long acting local anesthetic mixed with dexmedetomidine and dexamethasone can safely enhance immediate post-operative analgesia and decrease opioid consumption in the first 24 hours after surgery. A prospective randomized study is underway to further evaluate outcomes. This type of combination penile nerve block may also be a useful tool for other penile and scrotal surgeries. SOURCE OF Funding: Unfunded
