Comparison of IVC diameter ratio, BUN/creatinine ratio and BUN/albumin ratio for risk prediction in emergency department patients

Early prediction of patients' prognosis in the emergency department (ED) is important. Patients' conditions such as dehydration help predict prognosis. The ratio of serum blood urea nitrogen to creatinine (BUN/Cr ratio) and inferior vena cava (IVC) diameter is often used to determine dehydration. Also, serum albumin levels reflect nutritional conditions such as dehydration. In this study, we evaluated the performance of BUN/Cr ratio, IVC diameter ratio, and BUN/Albumin ratio as predictive markers for in-hospital mortality and ICU admission among various diseases in ED. This retrospective cohort study utilized data from patients who had abdominal and pelvic computed tomography (APCT) performed at our institution from 2015 to 2018. The measurement of IVC diameter from computed tomography, the BUN/Cr ratio, and the BUN/Albumin ratio were calculated. Differences in the performance among the BUN/Cr ratio, the IVC diameter ratio, and the BUN/Albumin ratio for predicting outcomes were evaluated by the area under the receiver operating characteristic (AUROC) curve. A total of 914 patients were enrolled and 78 patients (8.5%) were admitted to the ICU, and 71 patients (7.8%) died during the clinical process. Multivariate logistic regression showed that only the BUN/Albumin ratio was a significant predictor of inhospital mortality and ICU admission. Among dehydration markers the BUN/Albumin ratio is a simple and useful tool for predicting the outcomes of patients visiting the ED.