Perception-performance gap in trainee-performed pediatric caudal epidural block: Ultrasound verification of accuracy and clinical success

Background and Aims: USG guidance for caudal epidural block (CEB) improves precision. However, the reliability of sonographic signs in confirming proper placement remains underexplored. This prospective study aimed to evaluate the accuracy of trainee-performed landmark-based CEB placement, factors associated with first-pass accuracy, and reliable sonographic indicators of a successful block. Materials and Methods: After written informed consent, 70 ASA I-II children (1-12 years) undergoing infra-umbilical surgeries were enrolled. CEB was performed using the landmark technique. Saline spread, sacral canal dilatation, pumping sign, and needle visualization were recorded in transverse and longitudinal views. First-pass CEB placement accuracy, overall success rate, and factors influencing accuracy were analyzed. Univariate binary logistic regression was performed to assess the predictive value of individual ultrasonographic signs for block success. Results: The first-pass accuracy rate was 62.8%, with an overall success rate of 69%. Clear landmark palpation significantly improved first-pass accuracy ( P value < 0.05). Visualization of the needle tip in either transverse (OR 3.60, 95% CI 1.32-9.79, P = 0.01) or longitudinal (OR 2.66, 95% CI 1.00-7.07, P = 0.05) view and visualization of sacral canal dilatation (OR 5.25, 95% CI 1.81-15.23, P = 0.002) in the longitudinal orientation had a high odds ratio of a successful block. Conclusion: Landmark-based trainee-performed CEB has limitations, with a 62.8% first-pass accuracy and a 69% overall success rate. Reliable USG signs for block confirmation included needle visualization or sacral canal dilatation. Routine integration of USG is recommended to enhance the reliability of pediatric CEB.