The role of renal angina index and tissue perfusion indicators in predicting the development and stage of acute kidney injury in sepsis patients in intensive care unit: A prospective observational study

Accompanying acute kidney injury (AKI) is an important cause of morbidity and mortality in sepsis patients. Therefore, recognition of AKI is of great importance in the care of critically ill patients. In this study, we aimed to determine the role of the renal angina index (RAI) and tissue perfusion indicators in predicting early AKI and its stage in patients with sepsis. This study was performed prospectively on 40 sepsis patients in the Cukurova University Medical Intensive Care Unit between February 13 and December 1, 2023. Demographic data, clinical characteristics, capillary refill time, RAI, development of AKI, Intensive Care Unit, and 28-day mortality rates were evaluated. RAI (≥10) was found to be higher in patients with AKI and severe AKI (P < .001 and P = .001, respectively). Serum lactate levels at 24, 48, and 72 hours in the AKI group and serum lactate levels at all hours in patients with severe AKI were statistically significantly higher (P < .05). The rate of prolongation in capillary refill time was higher in patients with AKI and severe AKI (P < .05). The best cutoff for the RAI score to predict AKI severity was ≥10 with a 0.961 area under the curve, a sensitivity of 83.33%, and a specificity of 94.12%. A 24-hour lactate value of >2.1 mmol/L showed the best diagnostic performance with an area under the curve of 0.895, a sensitivity of 100%, and a specificity of 79.41%. The RAI score and 24-hour lactate demonstrated strong diagnostic performance in predicting AKI severity, with the RAI score showing superior accuracy. These markers, with high sensitivity and specificity, may serve as valuable tools for early risk assessment and clinical decision-making in AKI management.