Extracorporeal portal decompression using a graphite-benzalkonium-heparin shunt.

TREATMENT of bleeding esophageal varices remains a difficult problem. A significant number of patients with this condition are not suitable for emergency portasystemic venous shunt operations. Recent reports describe the usefulness of dilated umbilical veins in humans as an entry to the portal system for hepatoportography.1 7,8 XWhite,13 Piccone,9 and Christophersen 2 and co-workers used the umbilical vein for portal vein decompression. The accessibility of the umbilical and external jugular veins provides a simple means to construct a temporary extracorporeal portasystemic shunt to control bleeding varices. The dog is a good experimental animal for study of extracorporeal portasystemic shunts since it will not tolerate portal vein ligation.3 6 Canine survival after portal ligation is dependent upon adequate functioning of a shunt. Christophersen et al. concluded from experiments on dogs that anticoagulant agents were necessary to prevent clotting in extracorporeal shunts.2 The undesirability of anticoagulation in patients with bleeding esophageal varices is apparent. Gott and co-workers described a technic for preventing thrombosis on prosthetic materials by bonding heparin to a graphite-benzalkonium surface.4 The purpose of these experiments is to evaluate the effectiveness of extracorporeal portasystemic shunts in dogs without systemic anticoagulation employing tubes coated with grapbite-benzalkonium-heparin (GBH).