The importance of anticoagulation in COVID-19-related acute kidney injury requiring continuous renal replacement therapy

/Objective. In Serbia, the coronavirus disease 2019 (COVID-19) pandemic began in early March 2020. The aim of this study is to summarize clinical experience in the treatment of COVID-19-associated acute kidney injury by methods of continuous renal replacement therapy (CRRT) with the focus on the amount of the administered dose of unfractionated heparin. Methods. The study covers 12 patients treated with CRRT at the Clinic for Infectious Diseases at the Clinical Center of Vojvodina from March 6 to May 20, 2020. Antithrombotic prophylaxis, risk of venous thromboembolism (VTE), applied therapy, biochemical parameters before and after CRRT, anticoagulation and other CRRT parameters were analyzed. Results. The mean age of the patients was 61.54 ? 10.37 years and seven (58.3%) were men. All the patients received standard thromboprophylaxis. Nine (75%) patients had Padua Prediction Score for Risk of VTE ? 4, but none developed a thrombotic event. Seven critically ill patients with multi-organic dysfunction developed acute kidney injury dependent on CRRT. The mean CRRT dose was 36.6 ml/kg/h, the mean bolus dose of unfractionated heparin was 3250 ? 1138.18 IU, and the continuous dose was 1112.5 ? 334.48 IU/kg/h. Discontinuation of CRRT due to the clotting circuit was necessary in only one patient. The values of leukocytes, AST, ALT, GGT, aPTT, PT were significantly higher after CRRT compared to urea, creatinine, potassium, chlorine and magnesium, whose values were significantly lower. Conclusion. In our COVID-19 patients who had high inflammatory parameters and D-dimer and an estimated risk of developing deep vein thrombosis, the implementation pre-dilution continuous venovenous hemodiafiltration with antithrombotic membrane and 1/? to 1/? higher unfractionated heparin doses than the recommended one, the filter life lasted longer with no complications.