The aim of the research is to determine the prevalence of patients with acute kidney injury in the intensive care unit, the role of dialysis treatment in the treatment of these patients.

A retrospective and observational study was conducted in which the investigators included participants who were hospitalised in the Department of Internal Intensive Care Medicine at the University Hospital Maribor and who required replacement haemodialysis treatment during their hospital stay. The decision on haemodialysis treatment was made after an agreement between the attending specialist in intensive care medicine and the nephrologist if there was a clear indication for starting replacement haemodialysis treatment. It should be emphasised that each of the patients received an appropriate form of treatment according to indication and clinical condition, in line with all relevant recommendations and guidelines.

The investigators collected data on the underlying comorbidities, the indication for ICU treatment, the indication for starting haemodialysis treatment, the type of haemodialysis (continuous venovenous haemodialysis, continuous venovenous haemodiafiltration) and the basic parameters of haemodialysis (level of ultrafiltration and total ultrafiltration, anticoagulants used, duration of procedures, complications during haemodialysis, prescribed and achieved haemodialysis dose with emphasis on the amount of dialysate/substitute/ultrafiltrate used (Qe, effluent dose), number of haemodialysis procedures, dialysis membrane used with or without immunoadsorbent membrane). The investigators collected data on laboratory results (haemoglobin, leucocytes, platelets, C-reactive protein, procalcitonin, lactate, urea, creatinine, bilirubin, albumin, partial pressure of oxygen in arterial blood, myoglobin, lactate dehydrogenase, Interleukin-6, beta-2-microglobulin, cystatin C), some measured haemodynamic/vital parameters (mean arterial pressure, diuresis, oxygen demand) and the dose of vasopressor drugs during treatment. The investigators analysed all the data obtained and attempted to objectively evaluate the success of the treatment. The investigators compared different haemodialysis membranes (standard membranes for continuous haemodialysis vs. newer membranes such as Emic-2® and Oxiris membrane®), different dialysis techniques (haemodialysis vs. haemodiafiltration) and the effects of using the Cytosorb® immunoadsorptive membrane. The investigators have obtained data on the duration of hospitalisation and survival of participants after treatment (up to 1 year).

We analysed the data using basic statistical methods, where a value of p < 0.05 is considered statistically significant.

Inclusion Criteria:

• age >18 years,
• presence of acute kidney injury, stage 3 according to Kidney Disease:Improving Global Outcomes (KDIGO) criteria
• treatment with renal replacement therapy (RRT)

Exclusion Criteria:

• patients with chronic kidney disease (CKD) receiving chronic RRT
• previous known malignancy

All critically ill patients with stage 3 AKI who received RRT were included in the final study cohort.

There is a plan to make statistical data analysis available.

One year.

The member of the research team.