Portal Hypertension

Question 1

Normal hepatic venous pressure gradient

Answer 1

-Difference between wedged hepatic venous pressure and free hepatic venous pressure
-5-6mmHg

Question 2

What is clinically significant portal hypertension?

Answer 2

-Gradient exceeds 10mmHg
-Risk variceal bleeding increases beyond gradient of 12mmHg

Question 3

Causes of portal hypertension

Answer 3

1. Pre-hepatic pre-sinusoidal
2. Intrahepatic pre-sinusoidal
3. Sinusoidal
4. Intrahepatic post-sinusoidal
5. post-hepatic post-sinusoidal

Question 4

Pre-hepatic pre-sinusoidal causes

Answer 4

-Portal vein thrombosis due to sepsis (umbilical, portal pyaemia)
-Procoagulopathy or secondary to cirrhosis
-Abdominal trauma including surgery

Question 5

Intrahepatic pre-sinusoidal causes

Answer 5

-Schistosomiasis (most common cause worldwide infrequent outside endemic areas like Egypt)
-Congenital hepatic fibrosis
-Drugs
-Vinyl chloride
-Sarcoidosis

Question 6

Sinusoidal causes

Answer 6

-Cirrhosis
-Polycystic liver disease
-Nodular regenerative hyperplasia
-Metastatic malignant disease

Question 7

Intrahepatic post-sinusoidal causes

Answer 7

Veno-occlusive disease

Question 8

Post-hepatic post-sinusoidal causes

Answer 8

Budd-Chiari syndrome

Question 9

Clinical features of portal hypertension

Answer 9

-Splenomegaly
-Caput medusae= collateral vessels visible on anterior abdominal wall and radiate from umbilicus
-Cruveilhier-Baumgarten syndrome= large umbilical collateral vessel- venous hum
-Oesophageal, stomach and rectal varices
-Fetor hepaticus

Question 10

Complications of portal hypertension

Answer 10

-Variceal bleeding (oesophageal, gastric, other)
-Congestive gastropathy
-Hypersplenism
-Ascites (renal sodium retention)
-Iron deficiency anaemia
-Renal failure
-Hepatic encephalopathy

Question 11

Pathophysiology of portal hypertension

Answer 11

-Increased portal vascular resistance= gradual reduction in the flow of portal blood to the liver and simultaneously to the development of collateral vessels, allowing portal blood to bypass the liver and enter the systemic circulation directly.
-Portosystemic shunting occurs
-Stomal varices can also occur at the site of an ileostomy.
-As collateral vessel formation progresses, more than half of the portal blood flow may be shunted directly to the systemic circulation.
-Increased portal flow contributes to portal hypertension but is not the dominant factor.

Question 12

Investigations for portal hypertension

Answer 12

-Portal venous pressure measurement= differentiate sinusoidal and pre-sinusoidal forms
-Thrombocytopenia and leukopenia
-Endoscopy= gastro-oesophageal varices’
-Ultrasonography= splenomegaly and collateral vessels
-CT and magnetic resonance angiography= portal vein clot and hepatic vain patency

Question 13

Management of portal hypertension

Answer 13

-Prevention/ control of variceal haemorrhage
-Also from peptic ulceration

Question 14

Primary prevention of variceal bleeding

Answer 14

-Non-selective β-adrenoceptor antagonist (β-blocker) therapy with propranolol (80–160 mg/day) or nadolol (40–240 mg/day) is effective in reducing portal venous pressure
-Prophylactic banding= patients who are unable to tolerate or adhere to β-blocker therapy.
-Carvedilol, a non-cardio selective vasodilating β-blocker

Question 15

Management of acute variceal bleeding

Answer 15

-Restore circulation- shock reduces liver blood flow and further deterioration of liver function
-Restrictive transfusion (haemoglobin aim >70g/L) over liberal transfusion
-Endoscopy confirms source
-Prophylactic broad-spectrum antibiotics (IV cephalosporin or piperacillin/tazobactam- reduce incidence of spontaneous bacterial peritonitis)
-Vasoactive medications (terlipressin)
-Endoscopic banding
-PPI to prevent peptic ulcers
-Phosphate enema/ lactulose to prevent hepatic encephalopathy

Question 16

Describe Terlipressin

Answer 16

-Synthetic vasopressin analogue
-Intermittent injection
-Reduces portal blood flow and intrahepatic resistance= reduces portal pressure
-2mg IV 4 times daily until bleeding stops
-1mg 4 times daily up to 72 hrs
-Caution in severe ischaemic heart disease (vasoconstrictor)