Nerve stimulation guided bilateral pudendal nerve block versus landmark-based caudal block for hypospadias repair in young children: a prospective, randomized, pragmatic trial

Introduction Caudal block is frequently performed to provide analgesia for hypospadias repair. Literature suggests that pudendal block provides prolonged postoperative analgesia as compared with caudal block in children between 2 and 5 years. We compared the efficacy of pudendal and caudal blocks in children less than 2 years. Methods 60 children scheduled for hypospadias repair received standard general anesthesia along with either pudendal or caudal block (groups of 30 each). Variables collected were demographic data, block time, operating room time, intraoperative pain medication need, pain assessment score and medication need in the recovery room and pain assessment at home. Result Groups were demographically similar. No differences were observed in the following recorded times (minutes): block procedure (caudal: 9.5±4.0, pudendal: 10.6±4.1, p=0.30), anesthesia (caudal: 17.3±5.3, pudendal: 17.7±4.3, p=0.75), total OR (caudal: 171±35, pudendal: 172±41; p=0.95) and postanesthesia care unit (PACU) stay (caudal: 88±37, pudendal: 86±42; p=0.80). Additionally, no differences were observed in rescue pain medication need in the operating room (caudal: 0, pudendal: 2 (p=0.49), in PACU (caudal: 4, pudendal: 4, p=0.99), pain assessed at home, time to pain level 2 (caudal: 13.93±8.9, pudendal: 15.17±8.7), average pain scores (p=0.67) and total pain free epochs (pain level of zero) (p=0.80) in the first 24 hours. Discussion In children less than 2 years, both blocks provide comparable intraoperative and postoperative pain relief in the first 24 hours after hypospadias surgery. Trial registration number NCT03145415.