Risk Factors Predicting the Necessity of Renal Ultrasound in the Emergency Department

Objectives: Renal ultrasound (US) is widely used for diagnosing renal pathologies, though few of them, such as obstructive uropathy, require emergent urological intervention. During on-call hours, when medical staff is limited, it is important to prioritize which renal US examinations will be done. The aim of this study was to evaluate patient risk factors to predict the necessity of emergent renal US in the emergency department (ED). Material and Methods: All adult patients referred for renal US from the ED, during on-call hours from May 2015 to April 2017, were retrospectively included. The mean age was 64 years (18–98). Data were collected from the patients’ medical records. Urological intervention performed within the first 24 h following the US examination was recorded. Multivariate analysis was performed. Results: About 66% of the patients did not have a permanent urethral catheter, history of renal stones, or known abdominal or pelvic mass. None of these patients required an urgent urological intervention. The receiver operating characteristic curve was calculated at 0.883, 95% CI (0.84–0.92). Conclusion: Using only three variables, we can greatly reduce the number of renal US examinations done at on-call hours allowing for prioritization of only the necessary examinations.