Reducing Acute Kidney Injury Occurence by Administering Angiotensin II

Inclusion Criteria: * Adult patients undergoing cardiac surgery with CPB * Cardiac index 2.1l/min per square meter * Written informed consent * D-renin (difference between post- and preoperative) ≥ 3.7 micro Unit/ml 4 h after CPB * Postoperative hypotension requiring vasopressors Exclusion Criteria: * Preexisting AKI (stage 1 and higher) * Patients with cardiac assist devices * Pregnant women, nursing women and women of childbearing potential * Known (Glomerulo-) Nephritis, interstitial nephritis or vasculitis * chronic kidney disease with estimated glomerular filtration rate (eGFR) \< 30 ml/min * Dialysis dependent chronic kidney disease * Prior kidney transplant within the last to 12 months * Emergency surgery in the context of an acute coronary syndrome * Hypersensitivity to the active substance, or to any of the excipients of the study medication * Bronchospasm * Liver failure * Mesenteric ischemia * Participation in another intervention trial in the past 3 months * Persons with any kind of dependency on the investigator or employed by the institution responsible or investigator * Persons held in an institution by legal or official order