Hepatic Blood Flow Obstruction - Gastrointestinal

Introduction

Due to dual blood supply the liver does not typically infarct
Flow can be obstructed in 3 places
- pre-hepatic
  - caused mainly by vessel thrombosis
    - transplant rejection (hepatic artery)
    - polyarteritis nodosa (hepatic artery)
    - pyelphlebitis (portal vein)
    - hepatocellular carcinoma (portal vein)
- intra-hepatic
  - causes
    - cirrhosis
    - Budd-Chiari syndrome/centrilobular hemorrhagic necrosis
      - ischemic sequelae of heart failure
      - centrilobular region perfused last and is the first to infarct
- post-hepatic
  - caused by thrombosis of hepatic vein due to
    - malignancy invasion (e.g. hepatocellular carcinoma)
    - polycythemia vera
    - hypercoagulable states (e.g. pregnancy)
  - Budd-Chiari syndrome
    - occlusion of hepatic veins that causes blood to back up into the liver
      - can lead to centrilobular congestion and necrosis
        
        congestive liver disease can ensue with symptoms of:
        
        hepatomegaly
        
        ascites
        
        varices
        
        abdominal pain
        
        liver failure
        
        potential causes
        
        polycythemia vera
        
        CHF
        
        hepatocellular carcinoma
        
        postpartum state
        
        hypercoaguable state
        
        anything that causes hepatic vein thrombosis
        
        pathological findings
        
        classicaly described as a "nutmeg liver"
        
        treatment
        
        sodium restriction
        
        anticoagulation:
        
        heparin
        
        warfarin
        
        surgical shunts
        
        liver transplanation in patient with fluminant liver failure
        
        recurrence of disease is common

Presentation

Physical exam
- pre-hepatic
  - portal hypertension
  - ascites
  - NO hepatomegaly
- intra-hepatic
  - hepatomegaly
  - portal hypertension
  - ascites
- post-hepatic
  - hepatomegaly
  - portal hypertension
  - ascites

Evaluation

Intra-hepatic
- liver biopsy
  - "nutmeg" appearance
    - secondary to blood congestion/necrosis around central veins
- labs
  - ↑ transaminases
Post-hepatic
- ultrasound is test of choice
- labs
  - ↑ transaminases