Molecular adsorbent recirculating system and single-pass albumin dialysis in liver failure

Background: The aim of extracorporeal albumin dialysis (ECAD) is to reduce endogenous toxins accumulating in liver failure. To date, ECAD is conducted mainly with the Molecular Adsorbents Recirculating System (MARS). However, single-pass albumin dialysis (SPAD) has been proposed as an alternative. The aim of this study was to compare the two devices with a prospective, single-centre, non-inferiority crossover study design with particular focus on reduction of bilirubin levels (primary endpoint) and influence on paraclinical and clinical parameters (secondary endpoints) associated with liver failure. Methods: Patients presenting with liver failure were screened for eligibility and after inclusion were randomly assigned to be started on either conventional MARS or SPAD (with 4 % albumin and a dialysis flow rate of 700 ml/h). Statistical analyses were based on a linear mixed-effects model. Results: Sixty-nine crossover cycles of ECAD in 32 patients were completed. Both systems significantly reduced plasma bilirubin levels to a similar extent (MARS: median -68 mu mol/L, interquartile range [IQR] -107.5 to -33.5, p = 0.001; SPAD: -59 mu mol/L, -84.5 to + 36.5, p = 0.001). However, bile acids (MARS: -39 mu mol/L, -105.6 to -8.3, p < 0.001; SPAD: -9 mu mol/L, -36.9 to + 11.4, p = 0.131), creatinine (MARS: -24 mu mol/L, -46.5 to -8.0, p < 0.001; SPAD: -2 mu mol/L, -9.0 to + 7.0/L, p = 0.314) and urea (MARS: -0.9 mmol/L, -1.93 to -0.10, p = 0.024; SPAD: -0.1 mmol/L, -1.0 to + 0.68, p = 0.523) were reduced and albumin-binding capacity was increased (MARS: + 10 %, -0.8 to + 20.9 %, p < 0.001; SPAD: + 7 %, -7.5 to + 15.5 %, p = 0.137) only by MARS. Cytokine levels of interleukin (IL)-6 and IL-8 and hepatic encephalopathy were altered by neither MARS nor SPAD. Conclusions: Both procedures were safe for temporary extracorporeal liver support. While in clinical practice routinely assessed plasma bilirubin levels were reduced by both systems, only MARS affected other paraclinical parameters (i.e., serum bile acids, albumin-binding capacity, and creatinine and urea levels). Caution should be taken with regard to metabolic derangements and electrolyte disturbances, particularly in SPAD using regional citrate anti-coagulation.