Hypospadias repair, one of the most common urological procedures performed in boys, is associated with severe postoperative pain. Regional anesthesia has been used in addition to general anesthesia for years to provide adequate analgesia for this procedure. Caudal and penile blocks are preferred by pediatric anesthesiologists because of their ease of perform, effectiveness, and safety.1 Especially, when caudal block is performed preemptively, it also contributes to protecting patients from the undesirable effects of opioids by reducing intraoperative anesthetic agent consumption. Considering the neurotoxic effects of anesthetic drugs on the developing brain, the use of caudal block has retained its importance over the years.

Although the caudal block is considered safe and effective, recent findings present a confusing picture on its effect on surgical outcomes.2,3 Some studies argue that the caudal block increases postoperative complications, while others blame other factors.4, 5, 6, 7 However, there is no clear evidence that caudal block increases the rate of complications after hypospadias surgery in children. Nevertheless, this uncertainty continues to cast doubt on the caudal block, which has been safely performed by pediatric anesthesiologists for many years now.

Given the postoperative benefits of regional blocks, it is extremely important to understand the effects on complications such as urethrocutaneous fistula formation. In the literature, it has been reported that urethrocutaneous fistula formation occurs in 5–10 % following hypospadias repair.8 Identifying and controlling the factors affecting fistula development after hypospadias repair are critical for surgical success. Postoperative fistula formation may vary depending on many anatomic and surgical factors, rather than regional blocks (caudal or penile). However, the lack of clear evidence makes it difficult to establish this difference. Most studies on fistula development have been limited because they are either retrospective or observational.9 Thus, recent meta-analyses have highlighted the conflicting results of caudal block on postoperative surgical outcomes, emphasizing the need for further research regarding efficacy and safety.

It is increasingly important to determine whether high rates of urethrocutaneous fistula are due to caudal block or other confounding factors. We hypothesize that caudal block does not increase the urethrocutaneous fistula formation compared the other technics after hypospadias surgery. This study aims to evaluate the impact of caudal block on the rate of postoperative complications, especially urethrocutaneous fistula formation, in children undergoing hypospadias repair (primary outcome). Intraoperative and postoperative opioid consumption was also analyzed (secondary outcome).