1. PORTAL HYPERTENSION
- Defined as sustained elevation of portal pressure above 12mmHg (normal is 8-12mmHg)
Etiology
Presinusoidal
- Sinistral/extrahepatic
- Splenic vein thrombosis
- Splenomegaly
- Intrahepatic
- Schistosomiasis
- Congenital hepatic fibrosis
- Myeloproliferative disorder
Sinusoidal – cirrhotic
- Viral hepatitis
- Alcohol abuse
- Primary biliary cirrhosis
- Primary sclerosing cholangitis
Postsinusoidal
- Intrahepatic
- Vascular occlusive disease
- Posthepatic
- Budd-Chiari syndrome
- Congestive heart failure
Pathophysiology
- The portal venous system drains blood from the spleen, pancreas, gallbladder and abdominal portion of the GIT into the liver sinusoids
- Tributaries from the portal vein communicate with veins draining directly into the systemic circulation via portosystemic collaterals
- At normal portal vein pressure (5-10mmHg), little amount of blood is shunted from the portal venous circulation to systemic circulation
- A rise in portal venous pressure causes the portosystemic collaterals to dilate – so a large amount of blood can be shunted around the liver and into the systemic circulation
- Gastro-oesophageal – left gastric and short gastric veins anastomose with azygous vein
- Leads to oesophageal varices
- Umbilical – paraumbilical vein anastomosis with anterior abdominal vein
- Leads to caput medusae
- Anorectal – superior rectal vein anastomosis with middle and inferior rectal vein
- Leads to anorectal varices
- Retroperitoneal
Clinical features
- Classical triad – oesophageal varices, splenomegaly, acites
- Splenomegaly leads to functional hypersplenism – leukopenia, thrombocytopenia, anemia
- Caput medusae – appearance of distended and engorged paraumbilical veins, seen radiating from the umbilicus
- Anorectal varices
- Jaundice
- Encephalopathy
- Recurrent infections
Investigations
- Liver function test
- Ultrasound – dilated portal vein, collateral pathways
- Doppler US – to outline anatomy of the portal vein, establish direction of blood flow, exclude thrombosis
- CT/MRI – shows collateral pathways, splenomegaly, ascites
- Hepatic venous pressure gradient (HVPG) – balloon catheter is placed directly into the hepatic vein
- Free hepatic venous pressure (FHVP) is measured with the balloon deflated
- Wedged hepatic venous pressure (WHVP) is measured with the balloon inflated
- HVPG = WHVP – FHVP
- HVPG >10mmHg means there is clinically significant portal hypertension
Treatment
General measures
- Correct anemia
- Nutritional supplementation
- Vitamin K injection
Specific measures
- Treatment of oesophageal varices – see below
- Prevention of hepatic encephalopathy – lactulose, enema, antibiotics
- Treatment of ascites – diuretics, paracentesis, TIPS
Measures to reduce portal pressure
- Transjugular intrahepatic portosystemic shunt (TIPS) – stent to establish communication between the inflow portal vein and the outflow hepatic vein
- Surgical portocaval shunt – less common because of TIPS
- Drugs – propanolol, nadolol
Liver transplant
- Best option for patients with end stage liver disease
2. OESOPHAGEAL VARICES
Etiology
- Dilated and tortuous submucosal veins in the lower third of the oesophagus, most commonly due to portal hypertension
- Occur in 50% of patients with portal hypertension, especially in those with cirrhosis
Clinical features
- Patients are usually asymptomatic until a variceal haemorrhage
- Variceal haemorrhage – features of upper GI bleed
- Hematemesis
- Melena
- Syncope
Complications
- Hypovolemic shock
- Cardiac arrest
Investigations
- Oesophagogastroduodenoscopy – gold standard
- XR and barium swallow
- CT/MRI
Treatment
Emergency management in severe haemorrhage
- Drugs
- Vasopressin injection
- Somatostatin – reduces sphlanchnic and hepatic blood flow
- Propanolol = decreases portal pressure
- Endoscopic variceal banding (EVB) – gold standard
- Banded varices thrombose and slough off
- Endoscopic variceal sclerotherapy (EVS)
- Sclerosants (ethanolamine oleate, STDS) are injected into the varices
- ‘Seals’ off varices by vessel thrombosis, ulceration and submucosal fibrosis
- Procedure is done weekly for 6-8 weeks until varices are obliterated
-
Balloon tamponade – with a Sengstaken-Blakemore tube
- Gastric balloon is inflated to compress the GOJ, later the oesophageal balloon is inflated
- Oesophageal balloon should not be inflated for over 6 hours to avoid necrosis
- Complications – aspiration, airway obstruction, oesophageal perforation
Definitive management
- TIPS
- Surgical portocaval shunt
- Splenectomy – for sinistral portal hypertension
- Liver transplant