Evaluation of Clinical Characteristics and In-Hospital Outcomes of Critically Ill Patients Undergoing Hemodialysis or Continuous Venovenous Hemodiafiltration in the Emergency Department

Emergency renal replacement therapy may be required in critically ill patients with life-threatening conditions such as severe hyperkalemia, refractory metabolic acidosis, fluid overload or pulmonary edema, uremic complications, acute kidney injury, acute deterioration in patients with chronic kidney disease, sepsis-associated renal dysfunction, cardiorenal syndrome, or selected intoxications. In routine clinical practice, these patients are generally managed in intensive care settings. However, when intensive care capacity is limited or transfer to the hospital dialysis unit is not clinically feasible, renal replacement therapy may need to be initiated and continued in an emergency department critical care area.

This single-center, retrospective, observational, descriptive-analytical study will review the medical records of critically ill adult patients who received hemodialysis (HD) or continuous venovenous hemodiafiltration (CVVHDF) in the Emergency Department of Antalya Training and Research Hospital between January 1, 2023, and August 1, 2026. Data will be obtained from the hospital information management system, electronic medical records, laboratory records, clinical follow-up notes, renal replacement therapy records, and discharge summaries.

The study will characterize the clinical profile of patients requiring emergency renal replacement therapy and examine treatment indications, treatment modality, treatment course, pre- and post-treatment laboratory findings, treatment-related complications, and in-hospital clinical outcomes. Renal replacement therapy indications will be evaluated under predefined clinical categories, and patients with more than one indication may be classified in more than one category. Laboratory changes, particularly in potassium, pH, bicarbonate, urea, creatinine, and lactate, will be assessed using available routine clinical measurements before and after treatment.

The study is intended to provide descriptive and exploratory evidence regarding the use of HD and CVVHDF in critically ill patients managed in the emergency department and to contribute to the evaluation of emergency critical care processes in settings where intensive care capacity may be limited. No study-specific intervention will be performed, and all analyses will be based exclusively on routinely collected retrospective clinical data.