Objective: This study aimed to evaluate the potential role of the Peripheral Perfusion Index (PI) and arterial blood gas parameters as early indicators of acute kidney injury (AKI) and to compare their diagnostic utility with the Acute Kidney Injury Network (AKIN) and RIFLE scoring systems. We hypothesized that the PI is proportional to the severity of AKI and may aid in early diagnosis and prognosis of the disease.
Material and Methods: This prospective study included patients who received a new diagnosis of AKI in the emergency department (ED) of two tertiary hospitals based on AKIN and RIFLE criteria. Focusing on ED-diagnosed AKI ensures that the findings reflect early diagnostic decision-making in a time-sensitive setting, where rapid identification of AKI can impact immediate patient management and disposition. The PI of patients with confirmed AKI was measured using the necessary device, and a case report form was completed. This form recorded demographic characteristics, blood gas values, renal function tests, and AKIN and RIFLE scores.
Results: A total of 264 patients were included in this study. The study was divided into two groups: 132 cases (50%) and 132 controls (50%). A statistically significant difference was found between the case and control groups in terms of hypertension (p=0.001), coronary artery disease (p=0.009), pH (p=0.015), HCO3 (p=0.001), sodium (p=0.001), PI (p=0.001), urea (p=0.001), and creatinine (p=0.001). A statistically significant difference was found between AKIN score stages and RIFLE index stages regarding pH, CO2, HCO3, perfusion index, urea, creatinine, and potassium levels (p<0.05).
Conclusion: Our findings suggest that PI and blood gas analysis may serve as valuable adjuncts to conventional AKI classification, providing earlier insights into renal dysfunction.
Keywords: Acute kidney injury (AKI), AKIN Index, Perfusion Index, RIFLE score
