Portal hypertension - 浙江大学教学信息化平台.ppt

As early as the 17th century, it was realized that structural changes in the portal circulation could cause gastrointestinal bleeding. In 1902, Gilbert and Carnot introduced the term portal hypertension to describe this condition. Definition Portal hypertension is defined as a pressure 12 mmHg. This increased pressure results from a functional obstruction to blood flow from any point in the portal systems origin (in the splanchnic bed) through the hepatic veins (exit into the systemic circulation) or from an increase in blood flow in the system. Pathophysiology The normal pressure of portal vein: Anatomy of Portal System Ducts and vessles of the liver Four ramus communicans betweenportal and systemic circulations Etiology Types Portal hypertension should be divided into three types as its blood flow obstructed positions. Types pre-hepatic intra-hepatic pre-sinusoidal Sinusoidal post-sinusoidal post-hepatic Pre-hepatic type the portal vein trunk itself obstruction. Congenital deformity: obliteration, stenosis 先天性畸形：闭塞、狭窄 Thrombosis: portal vein thrombosis, splenic vein thrombosis, ect 血栓形成：门静脉、脾静脉 Infection: Tropical splenomegaly, ect 感染：热带巨脾综合症 Trauma: arterio-venous fistula, ect 创伤：动静脉瘘 Intra-hepatic type About 95% patients belong to this type of portal hypertension A classification by pathology: pre-sinusoidal obstructions sinusoidal obstructions post-sinusoidal obstructions Pre-sinusoidal obstruction Schistosomial cirrhosis. 血吸虫病 Schistosomial eggs deposit in small branches of portal vein, resulting in obstruction of blood flow and increase of portal vein pressure. Primary biliary cirrhosis 原发性胆汁性肝硬化 Chronic active hepatitis 慢性活动性肝炎 Sinusoidal obstruction Cirrhosis Post hepatitic cirrhosis, 肝炎后肝硬化 Alcohol cirrhosis, 酒精性肝硬化 Cryptogenic cirrhosis, 隐匿性肝硬化 Metabolic liver disease (e.g. Wilsons Disease) 代谢性疾病（Wilson’s 病） Non-cirrhotic Cytotoxic drugs, 细胞毒性药物 Vitamin A intoxication. 维生素A中毒 Po