This study aims to investigate shorter vs. standard filter lifespans in critically ill patients receiving continuous renal replacement therapy (CRRT) for acute kidney injury (AKI). The aim of this trial is to reliably implement,scheduled filter changes and to investigate whether shorter filter lifetime is associated with a lower incidence in rate of new infections.

Own data of patients under standard care indicated that a longer filter lifetime in CRRT is associated with an increased rate of new infections.

The aim of this study is to demonstrate that a protocolized filter-change strategy can be reliably implemented in critically ill patients and a high protocol adherence can be achieved.

The secondary aim is to investigate whether a shorter filter-change strategy is be associated with a lower incidence of newly acquired infections.

Inclusion Criteria:

1. Adult ≥ 18 years
2. Critically ill patients with severe AKI consistent with KDIGO stage 3 and an absolute indication for CRRT
3. Written consent form from the patient or legal representative or authorized representative or emergency inclusion

Exclusion Criteria:

1. End-stage kidney disease or chronic dialysis dependence
2. Chronic kidney disease with eGFR<20ml/min/1.73 m²
3. Prior kidney transplant
4. Prior renal replacement therapy during the index admission before randomization
5. Glomerulonephritis, interstitial nephritis, vasculitis
6. Patients on immunosuppression (above the cushing threshold)
7. Patients with chronic inflammatory diseases (e.g. arthritis, HIV with a CD4 count of < 0.05 x 10E/l)
8. Do-not resuscitate order
9. Persons with any kind of dependency on the investigator or employed by the sponsor
10. Patients participating in an interventional study involving measures to influence the immune system