Liver-Support Therapies
The liver performs hundreds of functions, including removing toxins, making clotting factors and proteins, regulating metabolism and clearing waste products. When it fails, these substances build up and damage other organs, especially the brain and kidneys. Liver-support therapies aim to reduce this toxic load and support the body while the liver recovers or a transplant becomes available. They do not replace all liver functions, and they are used as a bridge, not a cure.
Types of Liver-Support Therapies
Non-biological (artificial) systems
- Therapeutic plasma exchange (TPE): The patient's plasma is removed and replaced with donor plasma or albumin. This removes toxins, inflammatory mediators and ammonia, and replaces clotting factors. High-volume plasma exchange is supported by evidence and guidelines in acute liver failure and is being studied in ACLF.
- Albumin dialysis systems (MARS, Prometheus/FPSA): Blood is passed through membranes and an albumin-containing dialysate that binds and removes albumin-bound toxins such as bilirubin and bile acids. These have been used for severe jaundice, itching and encephalopathy in selected patients.
- Continuous renal replacement therapy (CRRT): Primarily supports failing kidneys but also removes ammonia and helps manage fluid and electrolyte balance in critically ill patients.
- Hemoadsorption and cytokine adsorption: Filters that remove inflammatory molecules and toxins. Evidence is still evolving, and they are used in selected cases.
- Single-pass albumin dialysis and other techniques: Available in some centres.
Biological and bioartificial systems
- Devices that use liver cells to provide synthetic and metabolic functions have been studied in trials, but are not yet in routine use. They remain largely in research settings.
Who May Benefit?
- Patients with acute liver failure, particularly as a bridge to spontaneous recovery or emergency transplant
- Patients with acute-on-chronic liver failure with worsening organ failure, in selected centres
- Patients with severe hepatic encephalopathy that does not respond to standard therapy
- Patients with severe cholestasis, intractable itching or very high bilirubin in specific contexts
- Patients with drug or toxin-related liver injury where removal of substances is helpful
- Patients with kidney failure due to liver disease needing dialysis
Goals of Treatment
- Lower ammonia and other toxins to protect the brain
- Reduce inflammatory mediators that drive multi-organ failure
- Improve circulation and stabilise organ function
- Replace clotting factors in plasma exchange
- Buy time for the native liver to regenerate
- Bridge to liver transplantation in suitable candidates
How Are They Done?
Treatment is carried out in the ICU by trained clinicians and nurses. A large catheter is placed in a vein, blood is drawn into a machine, treated and returned to the body. Sessions last several hours and may be repeated daily or on alternate days, depending on the therapy and the patient's response. Anticoagulation, temperature, blood pressure and electrolytes are monitored throughout the procedure.
Benefits
- Can improve alertness, blood pressure and biochemical markers
- May reduce the need for vasopressors in some patients
- May improve survival without transplant in selected acute liver failure patients
- Provides time for transplant preparation or organ allocation
- Available without the need for surgery
Risks and Limitations
- Bleeding or clotting at catheter sites or in the circuit
- Low blood pressure during the procedure
- Allergic reactions or fluid shifts with plasma replacement
- Infection related to catheters
- Electrolyte imbalance and low calcium
- Cost and access limited to specialised centres
- Benefits in some conditions, such as ACLF, remain under study, and not every patient improves
Because of these factors, decisions about liver-support therapy are individualised, made by an experienced team and revisited regularly.
Beyond Extracorporeal Therapy
Liver-support therapies are only part of care. They work best alongside treatment of the underlying cause, infection control, nutrition, organ support and early transplant planning. Newer approaches, including stem-cell based therapies, growth factors and improved devices, are under investigation, and patients may be offered participation in clinical trials at some centres.
Questions to Ask Your Care Team
- What is the goal of this therapy in my situation?
- What evidence supports it for my condition?
- What are the risks, and how will they be monitored?
- How many sessions are planned, and how will we judge response?
- What are the alternatives, and how does this affect transplant planning?
- What are the costs and insurance considerations?
