Table 1

Inclusion and exclusion criteria

  1. Severe AKI (KDIGO 3 classification) despite optimal resuscitation

    • Urine output of <0.3 mL/kg/hour for ≥24 hours.

    • Less than threefold increase in serum creatinine level compared with the baseline value.

    • Serum creatinine ≥4.0 mg/dL with an acute increase of ≥0.5 mg/dL.

  • Critically ill patients with an absolute clinical indication for CRRT

    • Urea serum levels >150 mg/dL.

    • Potassium serum levels >6 mmol/L.

    • Magnesium serum levels >4 mmol/L.

    • Blood PH <7.15.

    • Urine production <200 mL/12 hours or anuria.

    • Organ oedema in the presence of AKI resistant to diuretic treatment.

  1. At least one of the following conditions

    • Sepsis or septic shock (according to the most recent guidelines12).

    • Use of catecholamines (norepinephrine or epinephrine ≥0.1 µg/kg/min or norepinephrine ≥0.05 µg/kg/min+dobutamine (any dose) or norepinephrine ≥0.05 µg/kg/min+vasopressin (any dose) or epinephrine+norepinephrine ≥0.1 µg/kg/min).

    • Refractory fluid overload: worsening pulmonary oedema: PaO2/FiO2<300 mm Hg and/or fluid balance >10% of body weight).

  2. Age between 18 and 90.

  3. Intention to provide full intensive care treatment for at least 3 days.

  4. Written informed consent of the patient or his legal representatives or the authorised representative or inclusion due to an emergency situation.

  1. Patients with an increased bleeding risk or active bleeding due to vascular damage (ulcers in the gastrointestinal tract, hypertension with a diastolic blood pressure >105 mm Hg, intracranial haemorrhage or injuries (intracranial haemorrhage, aneurysm of brain arteries) or surgical procedures on the central nervous system (if according to neurologists or neurosurgeons a heparinisation with target aPTT of 45–60 s is not allowed), severe retinopathies, bleeding into the vitreum, ophthalmic surgical procedures or injuries, active tuberculosis, infective endocarditis).

  2. Diseases or organ damage related to haemorrhagic diathesis (coagulopathy, thrombocytopaenia, severe liver or pancreas disease).

  3. Dialysis-dependent chronic kidney insufficiency.

  4. Need of therapeutic anticoagulation (aPTT >60 s, anti-Xa >0.6 IE/mL, INR >2).

  5. Allergic reaction to one of the anticoagulants, ingredients or a known Heparin-induced thrombocytopaenia type II.

  6. AKI caused by permanent occlusion or surgical lesion of both renal arteries.

  7. AKI caused by glomerulonephritis, interstitial nephritis, vasculitis or urinary tract obstruction.

  8. Do-not-resuscitate order.

  9. Haemolytic uraemic syndrome/thrombotic thrombocytopaenic purpura.

  10. Persistent and severe lactate acidosis in the context of acute liver failure and/or shock.

  11. Kidney transplant within the last 12 months.

  12. Pregnancy and nursing period (female patients must be surgically sterile or postmenopausal for at least 2 years; or, if of childbearing potential, negative serum pregnancy test (due to intensive care treatment and severity of illness, sexual abstinence is warranted).

  13. Abortus imminens.

  14. No machine for CRRT free for use at the moment of inclusion.

  15. Participation in another clinical intervention trial in the last 3 months.

  16. Persons with any kind of dependency on the investigator or employed by the sponsor or investigator.

  17. Persons held in an institution by legal or official order.

  • AKI, acute kidney injury; aPTT, activated partial thromboplastin time; CRRT, continuous renal replacement therapy; FiO2, fractional inspired oxygen; INR, international normalized ratio; KDIGO, Kidney Disease: Improving Global Outcomes; PaO2, arterial oxygen tension.