Development of a laparoscopic approach to neurolytic celiac plexus block in a porcine model.

Abstract

Neurolytic celiac plexus block (NCPB) is an effective method of palliative pain control in cases of inoperable pancreatic cancer. This study was undertaken to evaluate the feasibility of a laparoscopic approach to NCPB in an experimental animal model. The laparoscopic technique for NCPB was developed in an acute study of six domestic swine followed by a chronic study of nine domestic swine that were monitored 3-21 days after surgery for adverse neurologic, gastrointestinal, or other sequelae. Using a four-port laparoscopic technique, the esophageal hiatus was dissected to expose the aorta at the level of the diaphragmatic crura. Under combined endoscopic and laparoscopic ultrasound (LUS) guidance, 5 ml of sclerosant dye (95% ethanol mixed with India ink) was injected into either side of the para-aortic soft tissue via a percutaneously placed 18-gauge spinal needle. After the animals were killed, the aorta and periaortic tissue were harvested from each animal for gross and histologic analysis. Under LUS guidance, sclerosant was injected successfully into the para-aortic soft tissue in all animals. There were no intraoperative complications in the acute animal group. Placement of sclerosant injection was successful in all nine chronic cases. Two pigs in the chronic study group died in the immediate postoperative period secondary to pneumothorax. No adverse neurologic, gastrointestinal, or other sequelae were observed in the remaining seven animals at 3-21 days postoperatively. After the animals were killed, we found no injuries to the aorta or esophagus, and histologic analysis demonstrated good placement of dye-labeled sclerosant with no compromise of aortic structural integrity. A laparoscopic approach to the aortic hiatus and NCPB is feasible. Further studies are warranted to evaluate this approach in patients who undergo staging laparoscopy for pancreatic cancer and are found to have unresectable disease.