Portal Hypertension

Pathophysiology

1) increased resistance to portal blood flow 2) by definition, pressure in portal system is > 10 mmHg (normal is 5-10 mmHg) 3) results in chronically diverted blood flow to systemic system, with resulting dilation of systemic venous channels 4) the cause of the increased resistance to portal blood flow is classified as presinusoidal (e.g., portal vein thrombosis, schistosomiasis), sinusoidal (e.g., cirrhosis), or postsinusoidal (e.g., Budd-Chiari)

Signs and Symptoms

1) gastroesophageal varices 2) rectal varices 3) caput medusa (engorged periumbilical veins running to thoracic margins bilaterally 4) splenomegaly 5) ascites 6) hepatic encephalopathy

Characteristic Test Findings

Radiology – reverse flow (hepatofugal flow) in portal vein on Doppler ultrasound; that is, the blood flows away from the liver instead of toward it.

Associated Conditions

1) cirrhosis 2) infection 3) pancreatitis 4) abdominal trauma 5) polycythemia vera 6) factor 5 Leiden 7) protein C deficiency 8) protein S deficiency

Inheritance/Epidemiology

most common cause by far in the USA is cirrhosis

Treatment

1) decompression with transjugular intrahepatic shunt (TIPS) procedure 2) propranolol for beta-adrenergic blockade

Tips for USMLE

if question mentions a 63 year-old female with chronic alcoholism and cirrhosis who develops sudden onset of ascites and a newly palpable enlarged spleen, think portal hypertension