Celiac plexus blockade is useful for diagnosing and treating pain of sympathetic origin. This includes pain involving the viscera, abdomen, and pelvis, secondary to cancer, complex regional pain syndrome, and vasospastic disorders.
After informed consent is obtained, the patient is placed in the prone position with a pillow under the abdomen. The inferior edge of the spinous process of the first lumbar vertebra and the lower border of each 12th rib at 7 cm from the spinous process of the first lumbar vertebra is identified and marked. The patient is prepared in a standard aseptic fashion over an area large enough to allow palpation of landmarks, and sterile technique is used throughout the procedure. A 6-in. (15-cm), 22-gauge needle is inserted at the mark on the 12th rib toward the spinous process of L1 at 60 degrees from perpendicular. The needle is advanced until it contacts the lateral side of the L1 vertebra. The depth is noted at this point. The needle is pulled back to a subcutaneous level and reinserted at 45 degrees toward the spinous process of L1 and slightly cephalad until it slips off the edge of the vertebra. This is about 2 to 3 cm deeper than the original depth. After negative aspiration, 20 mL of local anesthetic is injected (Fig. 67-8).
FIGURE 67-8. Celiac plexus block. Approach for celiac plexus injection and neural blockade.
This technique is commonly used for differential diagnosis and is the preferred treatment of sympathetic mediated pain involving the viscera and pelvis. The celiac plexus is located in the prevertebral region at the level of the L1 vertebral body. It is formed by the right and left celiacs, superior mesenteric, and aorticorenal ganglia. Autonomic mediated pain does not usually correspond to segmental or peripheral nerve distribution. Lateral and anteroposterior fluoroscopic views are recommended to ensure that the needle is properly positioned. It is recommended that intravenous access be available before the block in the event of hypotension from sympathectomy or toxicity from intravascular injection. It is necessary to perform this procedure bilaterally for a complete celiac plexus block. Rarely are ablative nerve procedures (neurolysis) required in the management of sympathetic mediated pain.
These injections are normally completed with fluoroscopic guidance, as noted in Chapter 68. Performance of this procedure out of a fully monitored environment is not recommended. Resuscitation equipment and personnel must be readily available. Although appearing technically simple, this block has multiple hazards, owing to the proximity of the aorta, kidney, pancreas, diaphragm, thoracic duct, and other vascular structures. Intraarterial or intradural injection of local anesthetic may result in death, seizure, respiratory arrest, cardiac arrest, cerebral damage with multiple sequelae, and other lesser complications. The risk for intravascular injection may be reduced if a test dose is given, the total dose is injected incrementally, and aspiration is performed before each injection.