Preliminary experiences of Rex shunt for extrahepatic portal vein obstruction via a conduit of internal jugular vein

Abstract

Objective To evaluate the outcomes of treating extrahepatic portal vein obstruction (EHPVO) by Rex shunt (superior mesenteric-left port vein bypass) with internal jugular vein graft. Methods From October 2014 to June 2015, 8 patients of extrahepatic portal vein obstruction underwent Rex shunting with internal jugular vein as a venous graft. The surgical outcomes were evaluated over a follow-up period of 1-9 months. A median longitudinal abdominal incision was made. After peritoneal cavity was satisfactorily opened, round hepatic ligament was resected and lifted. For inflow vein, left portal vein in Rex recess was liberated for around 3 cm. Superior mesenteric vein was identified by tracking mid-colon vein and dissected around 3 cm for outflow. Through 2 small transverse incisions on left side of neck, 7~9 cm of left internal jugular vein was harvested as a venous graft. Shunt was established by two end-to-side anastomoses at both ends of jugular vein graft between left portal and superior mesenteric veins. Results There were 5 boys and 3 girls with an average age of 4 (1.3~7) years. The manifestations included gastrointestinal hemorrhage (n=6), hypersplenism (n=6) and hemorrhage & splenomegaly (n=4). Preoperative liver function and blood coagulation were all normal while endoscopy revealed esophageal gastric varices (n=7). Portal vein cavernoma was identified by ultrasound and computed tomography (CT). Portal vein system retrograde angiography showed the presence of left portal vein bifurcation (n=7) and unidentifiable (n=1)(confirmed intraoperatively as atresia). Vascular patency of left portal vein in Rex recess was confirmed (n=7) during surgical exploration followed by Rex shunting. Warren shunt was performed for left portal vein atresia. After shunting, angiography through superior mesenteric vein demonstrated patency of vein graft, better development of intrahepatic portal system and regression of extrahepatic collateral varicose vessels. Portal vein pressure (PVP) was measured and compared during the procedure. Prior to opening shunting vessel, PVP was (27.00±3.74)mmHg and it declined remarkably to (19.00±2.71)mmHg after shunting. And the difference was significant [(8.00±3.42)mmHg, P=0.001]. During postoperative follow-ups, none of them had recurrent hemorrhage. Hypersplenism was controlled postoperatively (n=5) while there was no remission (n=1). Endoscopy at 6 months after operation revealed that esophageal gastric varices improved from severe to mild-moderate degree (n=3). Ultrasound showed patent portal vein without thrombosis or stenosis. And the postoperative diameter of left portal vein was (7.10±2.47)mm(3.3~10.5 mm). Conclusions Rex shunt reduces portal vein pressure and restores hepatic blood flow. It should be a first therapeutic choice for children with EHPVO. Key words: Mesenteric veins; Hypertension, portal; Portasystemic shunt, transjugular intrahepatic