[Physiopathology of portal hypertension (author's transl)].

The physiopathology of portal hypertension is discussed. The pathogenesis of this affection may be of a congenital, or acquired infectious or iatrogenic nature, and the percentage frequency of each of these causes is presented. The different morphological forms of portal hypertension in children are outlined, emphasis being placed on the fact that the blood obstruction is usually pre-hepatic in location. A study of the modifications in blood circulation due to the obstruction demonstrates the importance of the collateral network, both interior and exterior to the liver. Complications of portal vein thrombi include splenomegaly, ascites, and alterations in hepatic parenchymatous tissue, producing alteration in liver oxygen perfusion. The effect on the systemic circulation and brain function are discussed.