Caudal versus penile block and urethrocutaneous fistula formation following hypospadias repair in children <2 years: a multicenter randomized clinical trial
In brief
Urethrocutaneous fistula rates about 8% with caudal and 7% with penile block
In a multicenter randomized trial of children under two years, fistula formed in 8.9% after caudal block and 7.3% after penile block, showing no meaningful difference. Caudal block lowered intra-operative and rescue opioid use and produced lower pain scores in recovery. The study stopped early and follow-up was incomplete, so larger trials are needed to confirm safety and analgesic benefits.
- Journal
- Regional anesthesia and pain medicine (Q1)
- Published
- 11 September 2026
- Study design
- Randomized controlled trial
- Evidence level
- Level 1, High (CEBM 1b)
- Authors
- Andreas Taenzer, Tessa N Mandler, Alexia Gagliardi, Megan A Brockel, Vijaya Vemulakonda, Sophie R Pestieau, et al.
- PMID
- 42727983
- DOI
- 10.1136/rapm-2026-108027
Why clinicians should know about it
- Picked for Anesthesiology and Pain Medicine (paper of the day, 14 September 2026): Multicenter RCT, caudal vs penile block
Abstract
BACKGROUND: Retrospective studies report conflicting associations between caudal block and urethrocutaneous fistula (UCF) formation after hypospadias repair, often without control for hypospadias severity. Our multicenter randomized, non-inferiority trial compared UCF incidence following caudal versus penile block for single-stage hypospadias surgery. METHODS: Children ≤2 years undergoing primary single-stage midshaft or distal hypospadias repair at 16 Pediatric Regional Anesthesia Network centers were randomized to caudal (group C) or penile block (group P) with general anesthesia. The primary outcome was UCF formation within 3 postoperative months. Secondary outcomes included perioperative opioid administration, and postoperative pain scores (Face, Legs, Activity, Cry and Consolability (FLACC)). RESULTS: Of 210 subjects, 161 (76.6%) completed 3-month follow-up (group C: N=79; group P: N=82). UCF occurred in 7/79 (8.9%) group C and 6/82 (7.3%) group P patients (RR=0.98; 95% CI (0.35 to 2.76); p=0.9). Proximal meatal position was associated with increased UCF risk (RR=2.8; 95% CI (1.48 to 5.30); p=0.002). Group C received less intraoperative (33% vs 56%, p<0.001) and rescue opioids (4.9% vs 15.7%; p=0.01) and had lower mean postanesthesia care unit (PACU) FLACC scores (0.49±1.34 vs 1.14±2.3; p=0.03). CONCLUSION: In this early terminated randomized trial, no statistically significant difference in UCF formation was observed between caudal and penile blocks. Caudal block was associated with reduced perioperative opioids and lower pain scores. However, incomplete enrollment, loss to follow-up and wide CIs limit precision, and clinically important differences between the techniques cannot be excluded. The findings should be considered exploratory and may inform future trials and evidence generation. TRIAL REGISTRATION NUMBER: NCT02861950.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.