Palpation of the abdominal aorta

Definition:

The use of palpation to determine the approximate width and location of the abdominal aorta.

Test procedure:

Lay your patient slightly inclined with their knees bent and propped up so as to relax their abdomen. Starting at one side, gently palpate the area between the umbilicus and xiphoid, starting laterally, roughly at the linea semi-lunaris (lateral portion of the rectus abdominus) and moving medially towards the linea alba. Whilst doing so, the practitioner is attentively palpating for the pulsations of the abdominal aorta. Once the pulsations are felt, the practitioner keeps a finger-tip at that point ant repeats the procedure on the other side. The distance between the practitioner’s two finger-tips is than measured.

Test findings:

Most aneurysms are asymptomatic. Although as an abdominal aortic aneurysm expands, pain may ensue in the flanks, back, chest, scrotum and abdomen along with pulsations in the abdomen.
An aneurysm is typically an outer aortic diameter over 3cm (normal diameter is approximately 2cm). If the outer diameter exceeds 5.5cm, the aneurysm is considered large.

Special considerations:

Another test is to assess the patient’s blood pressure on both arms.
If there is a difference of greater than 10 mmHg between the two hands, this is abnormal and may indicate the development of an abdominal aortic aneurysm (AAA).

Contra-indication: if an AAA is suspected, do not palpate the aorta because added pressure may further damage or rupture the aorta. Referral to A&E is required.