The effects of acute kidney injury in the first 48 hours on clinical outcomes and mortality in COVID-19 patients admitted to the intensive care unit from the emergency department

Aims: The aim of this study was to evaluate the impact of acute kidney injury (AKI) in the first 48 hours on clinical outcomes and mortality in COVID-19 patients admitted from the emergency department (ED) to the intensive care unit (ICU). Methods: This retrospective observational cohort study, conducted at Pamukkale University Faculty of Medicine, analyzed 243 COVID-19 patients admitted to the ICU between March 2020 and 2023. Patients were divided into two groups according to the development of AKI based on serum creatinine (Scr) values assessed within the first 48 hours after ICU admission: group 1 (AKI-) without AKI (n=186) and group 2 (AKI+) with AKI (n=57). The two groups were compared in terms of clinical outcomes and mortality rates. Results: AKI+ patients were generally older and had higher mortality rates. AKI- patients were more likely to be discharged. AKI+ patients stayed in the ICU longer and required more treatment, including hemodynamic support, respiratory support, and renal replacement therapy (RRT). Scr levels were significantly different between groups at 24 and 48 hours. AKI+ patients had higher blood urea nitrogen (BUN), albumin, and BUN/albumin ratio (BAR) levels, indicating renal dysfunction and metabolic imbalances. In addition, procalcitonin levels were also significantly higher in AKI+ patients, suggesting an increased inflammatory or septic response. Other elevated markers included C-reactive protein (CRP), N-terminal pro-B-type natriuretic peptide (pro-BNP), D-dimer, and troponin T, indicating worsening cardiac and inflammatory conditions. Finally, AKI+ patients had lower APACHE II scores. Conclusion: In COVID-19 patients admitted from the ED to the ICU, developing AKI+ within the first 48 hours was associated with an increased risk of mortality and worse clinical outcomes. In contrast, AKI- patients showed more favorable clinical outcomes, including a higher chance of survival and less need for intensive interventions.