ABSTRACT
A caudal epidural block involves placing a needle through the sacral hiatus and delivering medication into the epidural space. The procedure is safe and simple, but failure rates can be as high as 25%. The purpose of this study was to investigate the success rate of caudal epidural block by analyzing needle placement and dye flow pattern.We retrospectively analyzed the medical records of patients who underwent caudal epidural block under spinal stenosis. A case was defined as a failure if it met at least one of the following four criteria: the epidural needle was not placed correctly inside the caudal canal; blood regurgitation or aspiration in the needle was observed; the contrast dye was injected into a blood vessel; or a large amount of the dye leaked into the sacral foramen or did not reach the L5-S1 level.At least 1 failure criterion was observed in 14 cases (17.7%), while none of the failure criteria were satisfied in 65 successful cases (82.3%).No matter how experienced the anesthesiologist may be, delivery of adequate therapeutic agent is not achieved in approximately 20% of cases. Therefore, we recommend fluoroscopy-guided needle placement and confirmation by radio-contrast epidurograpy as the best choice.
