In cirrhotic portal hypertension, these branches open in large numbers in order to allow the return of stagnant blood in the portal system and to allow the anastomosis of dilated or varicose veins with the veins of the body circulation to establish collateral circulation, so that portal blood can return to the right heart without passing through the liver. In cirrhosis, when the portal vein pressure increases above 200 mm water column, the flow of blood back to the heart from the normal digestive organs and spleen is blocked through the liver, resulting in the establishment of portal-body collateral circulation between many parts of the portal venous system and the vena cava. As a result of portal hypertension in cirrhosis, the normal hepatic portal vessels are blocked and blood enters the vena cava system through the anastomosis between the two. Due to the tiny veins at the anastomosis, the increased blood flow becomes varicose and once ruptured can lead to hemorrhage, such as vomiting blood, blood in the stool, and varicose veins will be seen around the umbilicus. How to diagnose portal collateral circulation: The establishment and opening of portal collateral circulation is a unique manifestation of portal hypertension, which is not only an important basis for the diagnosis of portal hypertension, but also has important clinical significance. Signs: The clinical manifestations of portal hypertension sign constitute three clinical manifestations of portal hypertension sign a splenomegaly, establishment and opening of collateral circulation, ascites, all of which are clinically significant. In particular, the establishment and opening of the collateral circulation has characteristic value for diagnosis. 1, Splenomegaly is often moderate, partly up to the umbilicus, mainly caused by splenic stasis, toxins and inflammatory factors, and the proliferation of reticuloendothelial cells is also related. 2.The establishment and opening of collateral circulation When the portal vein pressure increases beyond 1,96kpa (200mmH2O), the return blood flow from the digestive organs and spleen is blocked, forcing the establishment of collateral circulation between the vessels of many parts of the portal venous system and the body circulation. Some of the more clinically important ones are: ① varices of the lower esophagus and fundus, formed by anastomosis of the coronary veins of the portal vein system with the esophageal veins, intercostal veins, and odd veins of the vena cava system. The varices often rupture and hemorrhage due to significant increase in portal pressure, esophagitis, injury by rough and sharp food, or sudden increase in intra-abdominal pressure. The varicose veins of the abdominal wall and periumbilical region are reopened and enlarged during portal hypertension and connected with the paramedian umbilical vein and abdominal wall vein, etc. The twisted veins can be seen in the periumbilical abdominal wall and the direction of blood flow is upward above the umbilicus and downward below the umbilicus, which can be distinguished from inferior vena cava obstruction. If the umbilical vein is significantly varicose, the lumen is dilated and blood flow is increased, sometimes a continuous venous murmur can be heard. ③ Hemorrhoid nucleus formation, rupture can cause blood in the stool. 3, ascites is the most prominent manifestation of cirrhosis, the direct cause of the formation of ascites is excessive retention of water and sodium, the mechanism is the decrease in plasma albumin content resulting in a decrease in plasma colloid osmotic pressure, lymphatic reflux disorders, endocrine dysfunction and kidney and many other factors (see pathology), ascites appears before there is often intestinal distension, a large amount of ascites when the abdomen bulge, abdominal wall taut and shiny, resulting in the patient’s mobility, abdominal pressure increases It can compress the intra-abdominal organs and cause umbilical hernia, also can make the diaphragm elevated and cause dyspnea and palpitations, some patients can appear pleural fluid, more common on the right side, mostly due to ascites through the diaphragmatic lymphatics into the thoracic cavity, called hepatic pleural fluid. Above moderate ascites, mobile turbid sounds appear, and in small amounts of ascites, mobile turbid sounds are not obvious and can be detected with the help of ultrasound.