Extracorporeal Removal of Myoglobin in Patients with Rhabdomyolysis and Acute Kidney Injury: Comparison of High and Medium Cut-Off Membrane and an Adsorber Cartridge.

Introduction: The role of extracorporeal myoglobin removal in the treatment of rhabdomyolysis-associated severe acute kidney injury (AKI) is not yet fully established. High cut-off (HCO) and medium cut-off (MCO) dialysis membrane and cytokine adsorber (CytoSorb®) have been used to this purpose in clinical practice. The data on comparative effectiveness of those methods are scarce.

Methods: In this single-center retrospective study, we included patients with AKI and concomitant rhabdomyolysis (myoglobin >20,000 μg/L), who underwent at least one extracorporeal myoglobin removal procedure. The main outcome parameter was myoglobin reduction ratio, whereas albumin was assessed as a safety parameter.

Results: We analyzed data for 15 patients, who underwent 28 procedures (13 HCO, 9 MCO, and 6 adsorber). Pre-treatment serum myoglobin levels were similar between the groups and myoglobin reduction was significant in HCO (p = 0.03) and MCO groups (p < 0.01) and borderline significant in adsorber group (p = 0.06). Reduction ratios were comparable between the groups (median 0.64 (inter-quartile range IQR 0.13-0.72), 0.54 (IQR 0.51-0.61) and 0.50 (IQR 0.37-0.62), respectively, p = 0.83). Both pre- and post-procedure serum albumin levels were significantly lower in the MCO group. However, with routine albumin substitution in the HCO group only, serum albumin remained stable during the procedures in all subgroups.

Conclusions: Novel MCO membrane might represent the optimal mode of treatment of severe rhabdomyolysis-associated AKI, as it allows for efficient removal of myoglobin, avoids albumin supplementation and is associated with lower costs. For patients requiring cytokine removal, the adsorption capsule can simultaneously reduce cytokine and myoglobin levels.