What is the role of plasmapheresis (plasma exchange) in the treatment of acute liver failure?

Role of Plasmapheresis in Acute Liver Failure

Plasmapheresis serves as a temporary supportive measure in acute liver failure, primarily as a bridge to liver transplantation, which remains the definitive life-saving treatment for patients with acute liver failure. 1

Indications for Plasmapheresis in Acute Liver Failure

• Plasmapheresis is indicated as a bridging therapy until liver transplantation can be performed in patients with acute liver failure 1
• It is particularly valuable in Wilson's disease-related acute liver failure to acutely lower serum copper and limit hemolysis 2
• Plasmapheresis may protect the kidneys from copper-mediated tubular damage in Wilson's disease patients awaiting transplantation 1

Mechanism and Benefits

• Plasmapheresis helps remove toxins, ammonia, and other harmful substances that accumulate during liver failure 3, 4
• It can temporarily improve neurological status in patients with hepatic encephalopathy 3
• High-volume plasmapheresis (exchange of 8-12 L of plasma) may provide better outcomes than standard volume exchange 5, 6
• The procedure can stabilize patients with acute liver failure and delay, though not eliminate, the need for transplantation 1

Clinical Evidence and Outcomes

• Plasmapheresis has been shown to significantly decrease serum bilirubin, aspartate aminotransferase, and plasma ammonia concentrations 4
• Some studies report improvement in coma grade in up to 77% of patients with acute liver failure following plasmapheresis 4
• High-volume plasmapheresis can increase the time available to obtain a donor liver for emergency transplantation 7
• The procedure may optimize the patient's condition for the surgical transplantation procedure 7

Limitations and Considerations

• Plasmapheresis alone is not curative for acute liver failure 3
• Despite temporary improvement with plasmapheresis, many patients will still require liver transplantation as definitive treatment 1
• The procedure should be initiated early in the course of acute liver failure for optimal results 5
• Patients with Wilson's disease-related acute liver failure are considered to have uniformly fatal outcomes without transplantation, even with plasmapheresis 2

Alternative Liver Support Systems

• Albumin dialysis has also been shown to stabilize patients with acute liver failure due to Wilson's disease 1
• The Molecular Adsorbents Recirculating System (MARS) ultrafiltration device may be efficacious as an alternative to plasmapheresis 1
• Various liver support systems have been tested, but none have shown definitive evidence of efficacy beyond temporary improvement 2

Implementation Protocol

• For Wilson's disease-related acute liver failure, plasmapheresis should be implemented immediately while awaiting transplantation 2
• High-volume plasmapheresis typically involves exchanging 8-10 liters of patient plasma with an equal volume of fresh donor plasma 7
• The procedure can be performed daily until transplantation is available 7
• Patients should be monitored for potential complications, though major complications are rare when properly performed 7

Practical Considerations

• Plasmapheresis is more readily available in most hospitals compared to specialized liver support systems 5
• Early referral to a transplant center is essential for patients with acute liver failure, regardless of plasmapheresis initiation 2, 8
• The simplicity of the procedure compared to other extracorporeal support systems makes it a valuable option in facilities without access to liver transplantation 6