and Richard A. Jaffe2
(1)
David Geffen School of Medicine at UCLA, Los Angeles, California, USA
(2)
Stanford University School of Medicine, Stanford, California, USA
Keywords
EpiduralContinuous pressureEpidural anesthesia is an excellent anesthetic for many types of surgical procedures in the thorax, abdomen and lower extremities. When applicable, epidural anesthesia offers multiple advantages to patients as well as surgeons and anesthesia providers. Foremost among these is that as a continuous technique it can provide analgesia for operations of any length, and then be utilized in the postoperative period to provide analgesia for as long as deemed desirable. Depending upon the drugs selected for injection into the epidural space, and their volume and concentration, the anesthesia provider can provide analgesia, sensory or motor blockade or both over a wide area of the abdomen and extremities, or in a select area of the thorax, abdomen or legs. These choices are well described in the anesthesia literature. What are less well defined are the ideal technical aspects of performing an epidural.
Performing an Epidural
An epidural is best performed with the patient sitting because that position maximizes the flexion of the spine and optimizes the openings between the spinous processes . A second choice would be to have the patient lying laterally with the knees and head maximally flexed toward the abdomen. L2–3 or L3–4 are the ideal interspaces for performing the block, but it can also be performed at L4–5 or L5–S1, either in the midline or via a lateral approach. With the back prepped and draped, the anesthesia provider should inject a liberal dose of 1–2 % lidocaine at the chosen interspace, including the deeper tissues as well as the skin. If adequate local anesthesia is used, the remainder of the procedure should not be painful or even uncomfortable. A 19 g Huber-tipped, Tuohy, or similar needle is inserted in the midline, staying as close to the upper spinous process of the chosen interspace as possible, and directing the needle slightly cephalad. If bony tissue is encountered, move the needle more to the center of the interspace and continue to direct it slightly cephalad. If that is unsuccessful then move to the bottom of the interspace or move to another interspace.