Mount Carmel Health Partners Clinical Guidelines Abdominal Aortic Aneurysm

Abdominal Aortic Aneurysm Clinical Guideline Definition: An abdominal aortic aneurysm (AAA) is an enlargement of the lower part of the aorta that extends through the abdominal area (at times, the upper portion of the aorta in the chest can be enlarged). The aorta is the main blood vessel that carries blood from the heart to the rest of the body. Like most arteries, the aorta is elastic, which allows it to be filled with blood under high pressure. An aneurysm develops when the wall of the artery becomes weakened and distended like a balloon. No AAA suspected; are symptoms present? Yes Asymptomatic AAA Based on history and physical Evaluate for key symptoms: • back, flank, abdominal, leg, groin, scrotal pain • signs of aortic fistula • flank ecchymosis Evaluate for alternative symptoms: syncope, focal neurologic deficit (especially lower extremities), weakness, dizziness, GI bleed with anemia, anuria, or signs of limb ischemia Based on incidental imaging (spine MRI, US, CT, x-rays) Abdominal US imaging of choice Manage according to risk of rupture (see Table Three) Risk factor assessment (see Table One) Is imaging adequate at defining extent of aneurysm and maximum diameter including iliac arteries? Pre-notify vascular surgeon Yes Order abdominal and pelvic CT angiogram Is the patient hemodynamically unstable (SBP less than 100)? No No Yes Order abdominal and pelvic CT angiogram Physical exam suggests aneurysm and/or focused bedside ultrasound suggests aneurysm Manage according to risk of rupture (see Table Three) No Is aneurysm known? Yes Is AAA present? Yes Prepare and transfer to endovascular suite No Consider alternative diagnosis December 2015