A Prospective Observational Study on Renal Resistive Index as an Early Predictor of Hepatorenal Syndrome

INTRODUCTION: Cirrhosis is a major cause of illness and death, frequently leading to complications such as Hepatorenal Syndrome (HRS). Diagnosing HRS is difficult, as serum creatinine, commonly used to assess renal dysfunction, has significant limitations in cirrhotic patients. This study explored the Renal Resistive Index (RRI), measured using Doppler ultrasound, as a potential alternative for the early detection of renal dysfunction. OBJECTIVES: The primary objective is to calculate the RRI in cirrhotic patients and assess its predictive value for HRS. Secondary objectives include evaluating the correlation between RRI and liver disease severity (MELD and Child-Pugh scores) and exploring its relationship with ascites severity. MATERIALS AND METHODS: This study involved adult ICU patients diagnosed with liver cirrhosis. RRI values were measured using Doppler ultrasound, and relevant clinical data, including age, sex, ascites grade, Child-Pugh classification, and MELD-Na scores, were collected. Pearson correlation coefficients were calculated to assess relationships between RRI and clinical parameters, with a p-value of <0.05 considered statistically significant. Regression analysis was performed to evaluate RRI as an independent predictor of HRS, and ROC curve analysis was conducted to determine RRI's diagnostic accuracy. RESULTS: The sample predominantly consisted of middle-aged to elderly males, with alcohol as the leading cause of cirrhosis (78.2%). Approximately 50% of patients had ascites, and 64.1% were classified as Child-Pugh Grade A. Pearson correlation analysis revealed strong positive correlations between RRI and MELD-Na scores. An ANOVA test was done, and a significant relationship between RRI and Child-Pugh grades (p < 0.001) and ascitic severity (p < 0.001) was established. Regression analysis confirmed RRI as an independent predictor of HRS, with higher RRI values in HRS patients (0.729 ± 0.017 vs. 0.687 ± 0.018). ROC analysis indicated excellent predictive accuracy (AUC = 0.951); an RRI threshold of >0.705 provided 87.5% sensitivity and 87.0% specificity, while >0.715 improved specificity to 90.7%. CONCLUSION: This study highlights RRI as a promising early non-invasive predictor of HRS with a lead time advantage, supporting its integration into routine assessments. Future studies with larger, more diverse samples, hemodynamic optimisation based on RRI, and long-term follow-up are recommended further to validate RRI's clinical utility in cirrhosis management.