For continuous caudal block, insert a 19 gauge Touhy needle (A) or a 20 gauge intravenous catheter (B) through the sacrococcygeal ligament into the caudal space, as for single injection caudal block. Estimate the desired depth for catheter insertion, using the markings on the epidural catheter (C). Insert the catheter to the desired depth or until resistance is felt (D). Do not insert against resistance to avoid curling or knotting the catheter. If necessary, withdraw slightly and readvance. For further information refer to UpToDate content on caudal block.
