Figure 1:

Flowcharts of patients and circuit selection in both protocol groups. ¹ = circuit termination because of (i) diagnostic procedures or interventions outside the ICU, (ii) technical errors of the Prismax, and (iii) circuits that were ended because of the decision to cease CRRT. Reasons for partial non-protocol treatment in period 1 were: heparin: ECLS (extracorporeal life support system) treatment (two patients); frequent clotting (five patients), no anticoagulation: therapeutic anticoagulation due to thrombosis (one patient); liver failure (one patient), citrate, and heparin: COVID-19 (six patients), ECLS (one patient), other: modality switch from study period 1 to period 2 with exclusion of CRRT circuits of period 2 (one patient). Reasons for partly non-protocol treatment in period 2 were: heparin: ECLS (five patients); liver failure (two patients), no anticoagulation: liver failure with bleeding tendency (two patients), citrate and heparin: ECLS (two patients); COVID-19 (three patients).