Caudal block

Perspective

With advances in lumbar epidural anesthesia, caudal anesthesia has become an infrequently used and taught technique. Nevertheless, caudal anesthesia can be effectively used for anorectal and perineal procedures, as well as some lower extremity operations.

Patient Selection. Patient selection for caudal anesthesia should be determined by examining the anatomy of the sacral hiatus. In approximately 5% of adult patients, the sacral hiatus is nearly impossible to cannulate with needle or catheter; thus in 1 of 20 patients the technique is clinically unusable. Likewise, there are patients in whom the tissue mass overlying the sacrum makes the technique difficult, and if another technique is applicable, caudal anesthesia should be avoided. Probably more so than for any other block, experience and confidence on the anesthesiologist’s part are necessary to carry out the technique effectively.

Pharmacologic Choice. When choosing local anesthetics for caudal anesthesia, the same considerations as those applied to epidural anesthesia are needed. Volumes of local anesthetic in the 25- to 35-mL range are necessary to predictably provide a sensory level of T12 to T10 with caudal injection for adults.