Abstract Background Caudal blocks (CB) are a cornerstone of pediatric urologic surgery, providing effective analgesia while mitigating potential neurotoxicity associated with general anesthesia and opioids. However, the optimal timing of CB—preoperative versus postoperative—remains controversial. This study compares total opioid requirements in pediatric patients receiving preoperative versus postoperative CB to determine the timing that best minimizes opioid use. Methods All male patients aged 6–36 months who underwent urologic surgery from January 2019 to January 2023 at a single institution and had anesthesia care delivered by one of two attending pediatric anesthesiologists were retrospectively reviewed. One routinely administers preoperative CB following induction while the other performs postoperative CB immediately prior to emergence. Data collected included patient demographics, CB timing and dosage, opioid dosages, total anesthesia time, and postanesthesia care unit (PACU) time. Statistical analysis used Mann–Whitney U ‐test and chi‐square test, with results considered statistically significant at p < 0.05. Results 41 patients met inclusion criteria; 24 received preoperative CB, 17 received postoperative CB. There were no significant differences in age, weight, CB dose, total anesthesia time, or PACU time between the groups. Compared to the postoperative CB group, the preoperative CB group had significantly lower mean total opioid dose (3.875 vs. 26.470 mcg, p < 0.001), lower mean weight‐based dose (0.360 vs. 2.620 mcg/kg, p < 0.001), and fewer patients requiring opioids at all (37.5% vs. 94.1%, p < 0.001). Conclusion In this study, preoperative CB administration was associated with a significantly reduced cumulative opioid requirement in pediatric urologic surgery compared to postoperative administration.
Mendelson et al. (Thu,) studied this question.