Thoracoscopic splanchnicectomy for "small duct" chronic pancreatitis: case selection by differential epidural analgesia.

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. Recently, denervation of sympathetic pain afferents from the pancreas by surgical splanchnicectomy has shown promise in relieving pain while preserving residual pancreatic function. However, results from surgical splanchnicectomy have been mixed in large part because of patient selection. Differentiating actual pancreatic pain from "pancreatic" pain caused by drug-seeking behavior, psychogenic diseases, or various somatically innervated conditions is clinically challenging at best. Between 1992 and 1996, twenty-two patients with 20 prior pancreatic operations, "small duct" chronic pancreatitis, and "pancreatic" pain requiring narcotics were evaluated. Each underwent differential epidural analgesia (DEA) using the following standard techniques: placebo, low-dose (sympathetic), and high-dose (somatic) blocks. Pain perceptions were recorded before and after DEA using a visual analogue scale (VAS). Six demonstrated a greater than 50% decrease in VAS pain after placebo injection and were eliminated from further study. In the remaining 16 patients, pain relief only occurred with sympathetic or somatic blockade. Greater and lesser splanchnicectomy (surgical splanchnicectomy) was performed 27 times in these 16 patients (11 bilateral, 6 synchronous) (5 unilateral; 2 right and 3 left) using thoracoscopic techniques in 14 patients and open thoracotomy in two. No significant surgical or anesthetic complications were encountered. Surgical splanchnicectomy resulted in an overall significant reduction in preoperative VAS scores (8.25 to 4.18; P <0.05). Ten of 13 patients with DEA-predicted sympathetic pain experienced a greater than 50% decrease in VAS after surgical splanchnicectomy, but only two had complete relief. None of the three patients with DEA-predicted somatic pain were benefited by splanchnicectomy. During an average follow-up of 23.3 months, initial good results from surgical splanchnicectomy were maintained in 8 of 10 patients. The following conclusions were reached: (1) surgical splanchnicectomy is a safe, often effective technique for amelioration of intractable pain from "small duct" chronic pancreatitis and (2) DEA is a promising approach for identifying patients most likely to respond to surgical splanchnicectomy.