The caudal block is a pediatric regional anesthesia technique which allows the production of analgesia, easily and securely from S5 to T10. Is to produce nerve block by introducing a local anesthetic through the sacral hiatus into the sacral epidural canal in children under 8 years. Surgery is indicated below the diaphragm and contraindicated in sacral deformities, surgery perianal infections and bacteremia puncture site and, of course, in the coagulopathy.
The patient is placed in lateral decubitus or prone position with knees bent over his chest. Palpate the posterior superior iliac spines and visualize a triangle formed by the anterior superior iliac spines and, as a vertex, the sacral hiatus between the two horns sacred, through which it passes in sacral ligament (formed by the supra and interspinous ligaments and ligamentum flavum) above the buttocks, to the pictures.
The most common error is to insert the needle deep down, in the region of the coccyx. We use a 23 G needle (orange) or a 20-22 angiocath G. The inserted perpendicularly at the apex of the triangle in the midline, and then redirect, 45 º cranial direction. You will notice a "pop" of loss of resistance when the needle passes through the ligament between the sacrum and caudal space. Move only 1-2 mm and aim to check that there is no fluid or blood. At that time, inserted in catheter (epidural 20G) if we wish to postoperative analgesia than a few hours or directly inject the anesthetic, after test dose tested.
As a guide, we can say that, to achieve a T10 level of analgesia, use 0.25 cc / kgr of levobupivacaine 0.25% or ropivacaine 0.2%. To reach T6: we must use doses of 1-1.2 cc / kg. (Note: Be aware of the toxic dose).
most common mistakes, besides the aforementioned, are placing a needle under the skin, easily recognizable because it forms a wheal in the skin by injecting a local anesthetic and perform a subperiosteal injection, which is also recognizable, because we can not inject anesthetic.
I leave a video on youtube with the technique.
