Mesocaval Shunting: A Novel Technique to Facilitate Venous Resection and Reconstruction and Enhance Exposure of the Superior Mesenteric and Celiac Arteries during Pancreaticoduodenectomy

Abstract

Adequate exposure of the superior mesenteric artery (SMA) is necessary to facilitate a negative SMA margin, which represents the most critical oncologic step during pancreaticoduodenectomy for pancreatic cancer. For tumors inseparable from the superior mesenteric vein (SMV), or the SMV-portal vein (PV) confluence, which clearly require venous resection and reconstruction, SMA exposure and dissection is traditionally accomplished by 1 of 2 techniques. First, the SMA can be exposed medial to the SMV if the SMV-PV confluence is encased at the splenic vein (SV) confluence, and the SV can be divided, which widely exposes the SMA, as originally described by Fortner. However, if the inferior mesenteric vein (IMV) enters the SMV (rather than the SV), SV ligation may predispose to sinistral portal hypertension and gastrointestinal hemorrhage because retrograde decompression via the IMV is not possible. We have described the use of distal splenorenal shunting in such situations to allow SV decompression. If the SMV segment to be resected is distal to the splenic-portal junction, the SV does not need to be divided; however, this prevents easy access to the proximal SMA from this anterior approach and also prevents the PV from achieving increased length (for a primary anastomosis to the SMV). For these 2 reasons, some surgeons routinely divide the SV when performing segmental venous resection and reconstruction. However, preservation of the splenic-portal junction, if possible, is important because it essentially eliminates the risk of PV thrombosis or stenosis, which can occur after SMV-PV resection or reconstruction when the SV is divided. Alternatively, when resecting