Ischaemic hepatitis🎥
Ischaemic Hepatitis
Ischaemic hepatitis, also known as shock liver, is a form of acute liver injury resulting from a transient reduction in hepatic blood flow. It typically occurs in the context of hypotension, shock, or decompensated heart failure, leading to hepatocellular hypoxia and necrosis.
Peak Incidence
- Most commonly affects individuals between 50 and 80 years of age.
Pathophysiology
- A sudden drop in hepatic perfusion leads to hypoxic injury of hepatocytes.
- The central zones (zone 3) of the hepatic lobules are most vulnerable due to their relatively poor oxygen supply.
- Common triggers include cardiogenic shock, septic shock, massive blood loss, or acute decompensated heart failure.
Symptoms
- Many cases are asymptomatic and discovered incidentally on blood tests.
- If symptomatic, patients may report:
- Fatigue.
- Nausea and vomiting.
- Mild right upper quadrant (RUQ) discomfort.
- Jaundice (uncommon unless liver injury is severe).
Signs
- Features of hypotension or shock:
- Cold peripheries.
- Tachycardia.
- Altered mental status.
- Signs of heart failure (if relevant):
- Raised jugular venous pressure (JVP).
- Peripheral oedema.
- Hepatomegaly.
- Mild RUQ tenderness may be present.
Diagnosis
Blood Tests
- AST and ALT: Markedly elevated, typically >1000 IU/L. Levels often fall rapidly within a few days if the insult resolves.
- Bilirubin: May be elevated.
- Alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT): Normal or mildly raised.
- Prothrombin time (PT)/International Normalised Ratio (INR): May be prolonged, reflecting impaired synthetic function.
- Lactate: May be elevated if associated with shock or hypoperfusion.
Imaging
- Abdominal ultrasound or CT scan: Often normal but may show hepatic congestion in the context of heart failure.
- Echocardiography: Indicated if cardiac dysfunction is suspected as the precipitating cause.
Complications
- Acute liver failure (rare).
- Multi-organ failure (MOF).
- Coagulopathy due to impaired hepatic synthesis of clotting factors.
- Hepatic encephalopathy in severe cases.
- Acute kidney injury due to hypoperfusion.
Management
- Supportive care is the mainstay of treatment, as the liver injury is usually reversible.
- Close monitoring of liver function and coagulation profile.
- Treat the underlying cause:
- Optimise fluid status and blood pressure (e.g., IV fluids, vasopressors).
- Manage sepsis if present.
- Address underlying cardiac dysfunction or arrhythmia.
- Intensive care support may be required in severe cases.
FAQ from our users
What are the causes of ischaemic hepatitis?
- Severe hypotension
- Heart failure
- Sepsis
- Massive blood loss
- Respiratory failure
- Burns
- Thromboembolism
How long does ischaemic hepatitis last?
Liver enzymes typically peak within 24-72 hours and return to normal within 1-2 weeks if perfusion is restored.
Common pitfalls in a clinical setting
Common pitfalls in a clinical setting
- Do not forget to rule out other causes of acute liver injury when assessing someone with suspected ischaemic hepatitis, such as paracetamol overdose, viral hepatitis, or drug-induced liver injury.
- Do not delay treatment of shock or sepsis can worsen liver injury and lead to multi-organ failure.