Caudal epidural block in children: comparison of needle insertion parallel with caudal canal versus conventional two-step technique

Abstract

This study compared the technique of inserting the needle for caudal epidural blockade in a single pass parallel to the caudal canal versus the conventional technique of approaching the caudal canal with the needle at a steeper angle. Seventy-five patients, aged 0 to 72 months, scheduled for urological surgery were prospectively enrolled in this study. Patients were randomly divided into two groups: a conventional method group (caudal block performed with conventional needle insertion, n=40) and a new method group (needle inserted into the skin at an angle of 200 and into the caudal space without redirection, n=35). Two anaesthetists (A, B) performed the caudal blocks. For anaesthetist A, the mean time required (standard deviation) to perform needle insertion in the conventional method group was 2.2 (0.8) minutes and in the new method group 1.1 (0.7) minutes (P = 0.03). For anaesthetist B the mean time (standard deviation) to perform needle insertion in the conventional method group was 2.1 (1.1) minutes and in the new method group 1.3 (0.8) minutes (P = 0.04). Successful block was considered as first pass placement of the needle in the caudal canal confirmed (after placement) by ultrasound imaging, and the absence of a bloody tap. Subcutaneous placement of the needle after the first attempt occurred in two cases in the conventional method group and three cases in the new method group. Bloody tap occurred in four cases, all in the conventional method group and none in the new method group. When required, the second pass was successful in all cases.