A 62 year old man presents to the ED with a chief complaint of acute onset severe flank pain radiating to the groin for the past hour. He has a history of HTN and tobacco use. Vital signs are T 37C HR 115 BP 110/80 RR 20 SpO2 99%. On exam, he appears uncomfortable with CVA tenderness on the left. Of the choices below, which imaging modality should you pursue first?

1. CT with contrast
2. CT without contrast
3. POCUS
4. XR

Flank pain and CVA tenderness is concerning for nephrolithiasis and/or pyelonephritis, and ultimately this patient requires CT imaging. However, a ruptured AAA can also present similarly to renal colic. Therefore, you should first perform a quick POCUS at the bedside to examine the aorta for this patient with significant risk factors and abnormal vital signs

Aulivola B., Malinowski M. (2015) Abdominal Aortic Aneurysm. In: Saclarides T., Myers J., Millikan K. (eds) Common Surgical Diseases. Springer, New York, NY

See this prior EM Daily post about US findings for hydronephrosis, another possibility for this case: https://emdaily.cooperhealth.org/content/whats-diagnosis-dr-michael-tom-3