Continuous renal replacement therapy with the addition of CytoSorb cartridge in critically ill patients with COVID-19 plus acute kidney injury: A case-series

Our aim was to investigate continuous renal replacement therapy (CRRT) with CytoSorb cartridge for patients with life-threatening COVID-19 plus acute kidney injury (AKI), sepsis, acute respiratory distress syndrome (ARDS), and cytokine release syndrome (CRS). Of 492 COVID-19 patients admitted to our intensive care unit (ICU), 50 had AKI necessitating CRRT (10.16%) and were enrolled in the study. Upon ICU admission, all had AKI, ARDS, septic shock, and CRS. In addition to CRRT with CytoSorb, all received ARDS-net ventilation, prone positioning, plus empiric ribavirin, interferon beta-1b, antibiotics, hydrocortisone, and prophylactic anticoagulation. We retrospectively analyzed inflammatory biomarkers, oxygenation, organ function, duration of mechanical ventilation, ICU length-of-stay, and mortality on day-28 post-ICU admission. Patients were 49.64 +/- 8.90 years old (78% male) with body mass index of 26.70 +/- 2.76 kg/m(2). On ICU admission, mean Acute Physiology and Chronic Health Evaluation (APACHE) II was 22.52 +/- 1.1. Sequential Organ Function Assessment (SOFA) score was 9.36 +/- 2.068 and the ratio of partial arterial pressure of oxygen to fractional inspired concentration of oxygen (PaO2/FiO(2)) was 117.46 +/- 36.92. Duration of mechanical ventilation was 17.38 +/- 7.39 days, ICU length-of-stay was 20.70 +/- 8.83 days, and mortality 28 days post-ICU admission was 30%. Nonsurvivors had higher levels of inflammatory biomarkers, and more unresolved shock, ARDS, AKI, and pulmonary emboli (8% vs. 4%, P < .05) compared to survivors. After 2 +/- 1 CRRT sessions with CytoSorb, survivors had decreased SOFA scores, lactate dehydrogenase, ferritin, D-dimers, C-reactive protein, and interleukin-6; and increased PaO2/FiO(2) ratios, and lymphocyte counts (all P < .05). Receiver-operator-curve analysis showed that posttherapy values of interleukin-6 (cutoff point >620 pg/mL) predicted in-hospital mortality for critically ill COVID-19 patients (area-under-the-curve: 0.87, 95% CI: 0.81-0.93; P = .001). No side effects of therapy were recorded. In this retrospective case-series, CRRT with the CytoSorb cartridge provided a safe rescue therapy in life-threatening COVID-19 with associated AKI, ARDS, sepsis, and hyperinflammation.