Predictors of Hospital Admission and Urological Intervention in Adult Emergency Department Patients with Computerized Tomography Confirmed Ureteral Stones.

ABSTRACT

PURPOSE: More than 1 million patients annually seek care in an emergency department for kidney stones but a minority require hospital admission or a urological procedure. We describe predictors of hospital admission or urological intervention. MATERIALS AND METHODS: This secondary analysis of prospective data included patients with an obstructing ureteral stone that was confirmed by computerized tomography in an emergency department. All patients also underwent point of care limited renal ultrasound. The need for urological intervention at 90 days was assessed by a followup interview. Logistic regression was used to identify predictors of admission and urological intervention, which were further stratified by disposition. Separate regression models with and without computerized tomography findings (point of care limited renal ultrasound only) were compared using c-statistics. RESULTS: Among a cohort of 475 patients with a symptomatic stone on computerized tomography 95 (20%) were admitted and 68 (72%) received an intervention. Of 380 discharged patients 66 (17%) required urological intervention. Admitted patients were more likely to have undergone a prior procedure, have evidence of kidney injury or infection, need opiate analgesia or have larger stones or hydronephrosis on point of care limited renal ultrasound. Predictors of intervention varied by disposition. However, regression models with and without computerized tomography findings demonstrated similar c-statistics. Discharged patients with larger stones, a longer pain duration at presentation and prior procedures were more likely to undergo intervention. CONCLUSIONS: Intervention was common among admitted patients but it occurred in a minority of those discharged. Predictors of intervention varied by disposition. Models incorporating computerized tomography findings were similar to those that did not incorporate such findings. These data support ultrasound first or delayed computerized tomography diagnostic pathways for patients deemed clinically suitable for discharge home.