In order to determine the influence of complete blockage of lymph flow on temporary ischemic liver damage, we operated on 46 mongrel dogs. In group 1, we induced liver ischemia in 4 dogs for 60 min by occlusion of the afferent hepatic vessels (hepatic artery and portal vein), subsequent to portal decompression by a portocaval H-shunt. In group2, we carried out an additional lymph flow blockage by dissection of all connective tissue from the liver in 4 dogs. As only one dog survived in group 2, further experiments were performed with 45-min ischemia. In groups 3 and 4, we induced 45-min ischemia with subsequent biochemical and histological studies, respectively, for 5 weeks postoperatively in a total of 20 dogs. Groups 5 and 6 were treated like groups 3 and 4, but with additional blockage of lymph flow. In groups 3 and 4, no animals died, whereas 4 of 18 dogs died in groups 5 and 6. We found much higher levels of enzymes (GOT up to 1124.8 + 560.9; GPT up to 1139.9 + 475.8 and alkaline phosphatase up to 896.8 + 264.8mU/ml) in group5 than in group3 (GOT up to 88.7+26.9; GPT up to 94.8+27.4 and alkaline phosphatase up to 60.9 + 10.8 mU/ml). In group 3, values returned to normal 3-5 days after surgery compared to 3 weeks and longer in group 5. Besides necrosis and cell infiltrations the histological studies showed edematous changes and a lymphostatic hemangiopathy. The histological damage corresponded to the biochemical changes. It was concluded that additional blockage of lymph flow leads to potential ischemic liver damage.