Nerve blocks and neuroablative surgery for chronic pancreatitis

Surgical decompressive procedures for "large-duct" chronic pancreatitis have been notably successful in relieving pain. However, management of patients with intractable pain from "small-duct" chronic pancreatitis has been difficult, often resulting in narcotic addiction and/or malnutrition from major pancreatic resection. In view of the disappointing results from extensive pancreatic resections in these cases, denervation of pancreatic sympathetic pain afferents has been suggested as an alternative. Although denervation procedures have been attempted at multiple anatomical levels, results have unfortunately been mixed. The observed variability in results has been attributed to poor patient selection, incomplete understanding of neurophysiology of pancreatic pain, and perhaps inadequate knowledge of pancreatic neuroanatomy. At present, the preferred form of neural ablation is splanchnicectomy. However, a consistent and reliable method for identifying candidates for splanchnicectomy is critical, as it is clinically difficult to distinguish true pancreatic pain from other nociceptive conditions masquerading as pancreatic pain. Differential epidural anesthesia (DEA) is a promising, safe test for initial evaluation and patient selection, although it is not as precise as sometimes claimed. Patients responding to sympathetic block during DEA seem to be the best candidates for operative sympathetic ablation. At the moment, the optimal surgical approach to splanchnic ablation, which offers the least morbid technique, most favorable results, and an attractive risk-benefit ratio, is bilateral thoracoscopic splanchnicectomy. More experience and longer follow-up will be necessary to evaluate this approach.