Final answer:
The TIPSS procedure reduces portal hypertension by uniting the portal vein and the hepatic vein, creating a shunt to bypass the liver and improve blood flow.
Step-by-step explanation:
The TIPSS (Transjugular Intrahepatic Portosystemic Shunt) procedure is designed to reduce portal hypertension by uniting the portal vein and the hepatic vein. Portal hypertension occurs when there is increased pressure in the portal vein, which brings blood from the digestive organs to the liver. TIPSS creates a shunt between the portal vein and the hepatic vein to bypass the liver, reducing the pressure and improving blood flow. This procedure is commonly used to treat complications of liver cirrhosis.