The only supportive therapy for patients with severe acute kidney injury (AKI), a common complication among the critically ill, is dialysis. Based on the literature and current guidelines, continuous renal replacement therapy (CRRT) with a total effluent dose of 20–25 mL/kg/hour and adjustments to ensure such dose is delivered despite down time (eg, due to surgical procedures) is recommended. However, experimental and clinical studies suggest that azotaemia, which can be induced by lowering the effluent dose, may accelerate renal recovery. This clinical study investigates whether a lower effluent dose (10–15 mL/kg/hour) for a maximum of 7 days or until successful (>24 hours) liberation of CRRT in critically ill patients with a dialysis-dependent AKI accelerates renal recovery and reduces time on CRRT compared with guideline-directed standard dose (25–30 mL/kg/hour).

The Ketzerei trial is an international, multicentre randomised, controlled trial, designed to investigate if a lower effluent dose (10–15 mL/kg/hour) accelerates renal recovery and reduces the time on CRRT compared with the guideline directed standard effluent dose (25–30 mL/kg/hour). The study aims to enrol 150 critically ill patients with a dialysis-dependent AKI. Eligible patients will be randomised to receive either a standard effluent dose (control group, 25–30 mL/kg/hour) or lower effluent dose (interventional group, 10–15 mL/kg/hour). The primary endpoint is the number of days free from CRRT and alive (from randomisation through day 28). Key secondary endpoints include the number of (serious) adverse events due to potential uremia, the duration of RRT and intensive care unit survival.

The Ketzerei trial has been approved by the Ethics Committee of the Chamber of Physicians Westfalen-Lippe (2023–343 f-s), the University of Muenster and subsequently by the corresponding Ethics Committee of the participating sites. Results will be disseminated widely and published in peer-reviewed journals, presented at conferences and will guide patient care and further research.

clinicaltrials.gov (NCT06021288).

Acute kidney injury (AKI) is a major complication after cardiac surgery and is associated with postoperative morbidity and mortality. Currently, no effective therapy exists to reduce the incidence of postoperative AKI. Sodium-glucose cotransporter-2 (SGLT2) inhibitors are effective in reducing AKI in outpatient settings for patients with chronic kidney disease. We hypothesised that perioperative SGLT2 inhibition will also reduce AKI incidence after cardiac surgery according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria.

We designed a multicentre, randomised, placebo-controlled, triple-blinded, superiority trial. A total of 784 patients, aged above 18 years, undergoing cardiac surgery will be included with stratification for sex and type 2 diabetes in a 1:1 ratio. Patients will receive either dapagliflozin 10 mg or placebo from the day before until 2 days after surgery. Serum creatinine will be measured preoperatively and daily for the first 7 days after the operation, and urine output will be measured until the urinary catheter is removed. The primary outcome is the incidence of postoperative AKI according to the KDIGO criteria.

The medical ethics committee of the Amsterdam University Medical Centre (UMC) and the Dutch competent authority approved the study protocol (currently, version 9, 19 January 2024). This is an investigator-initiated study. The Amsterdam UMC, as sponsor, retains ownership of all data and publication rights. After completion of the trial, results will be disseminated to participants, patient societies and physicians via a network meeting and digital newsletter. Results will be submitted for publication in a peer-reviewed international medical journal and presented on (inter)national congresses.

Clinicaltrials.gov identifier: NCT05590143.