[Portal shunt operations. A critical observation on the selection of shunt methods].
In prehepatic block the method of operation is dependent on the anatomical and pathological condition of the blood vessels in the portal system. The choice of the shunt method has significant importance for the further progress of the disease and the social reintegration of the liver cirrhotic patients. Here, special attention should be given to possible postoperative hepatoportal encephalopathies. Portal hypertension is completely averted by direct portacaval anastomosis. It has a low risk but a relatively high incidence of postoperative encephalopathy. The lateral splenorenal shunt has a higher rate of recurrent bleeding but lower lethality, a higher long term survivalrate and a smaller number of encephalopathies. The coronariocaval anastomosis showed specially good results. This method is however only practicable in cases with extremely dilated coronaric ventricular veins. In the prevention of postoperative encephalopathies the central splenorenal anastomosis by Warren, Zeppa and Fomon has proved most effective. Modifications in method, especially the approach through the bursa omentalis and omission of the ligatur of the coronaric vein permits a significant decrease in the inherent surgical lethality. The pressure adapted arterialisation of the portal stump in portacaval shunt with iliacoportal bypass with saphenous vein interposition, as evolved by Matzander, seems to cause a significant decrease in the rate of postoperative encephalopathies after portacaval anastomosis. The prevention of postoperative encephalopathy is still the main problem of the technically perfected shunt operations. Solving this problem requires further investigation and research.