Use of the Molecular Adsorbent Recirculating System in Acute Liver Failure: Results of a Multicenter Propensity Score-Matched Study

Objectives: The molecular adsorbent recirculating system removes water-soluble and albumin-bound toxins and may be beneficial for acute liver failure patients. We compared the rates of 21-day transplant-free survival in acute liver failure patients receiving molecular adsorbent recirculating system therapy and patients receiving standard medical therapy.

Design: Propensity score-matched retrospective cohort analysis.

Setting: Tertiary North American liver transplant centers.

Patients: Acute liver failure patients receiving molecular adsorbent recirculating system at three transplantation centers (n = 104; January 2009-2019) and controls from the U.S. Acute Liver Failure Study Group registry.

Interventions: Molecular adsorbent recirculating system treatment versus standard medical therapy (control).

Measurements and main results: One-hundred four molecular adsorbent recirculating system patients were propensity score-matched (4:1) to 416 controls. Using multivariable conditional logistic regression adjusting for acute liver failure etiology (acetaminophen: n = 248; vs nonacetaminophen: n = 272), age, vasopressor support, international normalized ratio, King's College Criteria, and propensity score (main model), molecular adsorbent recirculating system was significantly associated with increased 21-day transplant-free survival (odds ratio, 1.90; 95% CI, 1.07-3.39; p = 0.030). This association remained significant in several sensitivity analyses, including adjustment for acute liver failure etiology and propensity score alone ("model 2"; molecular adsorbent recirculating system odds ratio, 1.86; 95% CI, 1.05-3.31; p = 0.033), and further adjustment of the "main model" for mechanical ventilation, and grade 3/4 hepatic encephalopathy ("model 3"; molecular adsorbent recirculating system odds ratio, 1.91; 95% CI, 1.07-3.41; p = 0.029). In acetaminophen-acute liver failure (n = 51), molecular adsorbent recirculating system was associated with significant improvements (post vs pre) in mean arterial pressure (92.0 vs 78.0 mm Hg), creatinine (77.0 vs 128.2 µmol/L), lactate (2.3 vs 4.3 mmol/L), and ammonia (98.0 vs 136.0 µmol/L; p ≤ 0.002 for all). In nonacetaminophen acute liver failure (n = 53), molecular adsorbent recirculating system was associated with significant improvements in bilirubin (205.2 vs 251.4 µmol/L), creatinine (83.1 vs 133.5 µmol/L), and ammonia (111.5 vs 140.0 µmol/L; p ≤ 0.022 for all).

Conclusions: Treatment with molecular adsorbent recirculating system is associated with increased 21-day transplant-free survival in acute liver failure and improves biochemical variables and hemodynamics, particularly in acetaminophen-acute liver failure.