Comparison of the Analgesic Efficacy of Ultrasound-Guided Transperineal Approach Using Pudendal Nerve Block Versus Caudal Block in Children Undergoing Urological Surgeries: A Randomized Controlled Trial

Cureus. 2024 Nov 22;16(11):e74244. doi: 10.7759/cureus.74244. eCollection 2024 Nov.

Abstract

Introduction: Caudal block is an effective regional anesthesia technique for perineal surgeries but is associated with various adverse effects. Recently, pudendal nerve block has emerged as a promising alternative for these procedures. This study assessed the effectiveness of a novel transperineal technique for ultrasound-guided pudendal nerve block and compares it with ultrasound-guided caudal block for perineal surgeries in pediatric patients.

Methods: The study included 60 American Society of Anesthesiologists (ASA) Physical Status Classification System grade I/II children aged 1-12 years and scheduled for elective perineal operations under general anesthesia. Patients were randomly allocated to two equal groups: Group C (ultrasound-guided caudal block) and Group P (ultrasound-guided pudendal nerve block). The groups were evaluated for time to first rescue analgesia (primary outcome), block performance time, total analgesic consumption, Face, Legs, Activity, Cry, and Consolability (FLACC) scores, time to achieve a Post-Anesthetic Discharge Scoring System (PADSS) score of 9, and any complications.

Results: The median interquartile range (IQR) first rescue analgesia time was significantly higher in the pudendal block (17.5 (17-18) hours vs 4.65 (4.5-4.77) hours; p<0.001). The median (IQR) dose of postoperative analgesia (diclofenac) required was similar in the pudendal block group and caudal group (10 (0-10) mg vs 10 (0-20) mg; p=0.290). The median (IQR) FLACC scores at "zero" hour post-surgery were 2 (2-2) and 2 (1-2) in the pudendal and caudal groups, respectively (p=0.052). The median (IQR) PADDS score was significantly higher in the pudendal group (10 (9.25-10) vs 9 (8-9); p<0.001). The time to reach a PADSS score of 9 was significantly longer in the pudendal group (21.4±3 vs 14.9±4.8 hours; p<0.0001). There were no complications in either group.

Conclusions: The findings of this study suggest that pudendal nerve block provides longer-lasting analgesia, lower pain scores, and faster readiness for discharge though with a similar analgesic consumption compared to caudal block. These results indicate the potential of ultrasound-guided pudendal nerve blocks as a beneficial and safe alternative to caudal block for perineal procedures in children.

Keywords: caudal block; pediatrics; perineal surgeries; postoperative analgesia; pudendal nerve block; regional anesthesia; ultrasound guided regional anesthesia.