Ankle–brachial pressure index Ankle–brachial pressure index The ankle-brachial pressure index (ABPI) or ankle-brachial index (ABI) is the ratio of the blood pressure at the ankle to the blood pressure in the upper arm (brachium). Compared to the arm, lower blood pressure in the leg suggests blocked arteries due to peripheral artery disease (PAD). The ABPI is calculated by dividing the systolic blood pressure at the ankle by the systolic blood pressure in the arm. The patient must be placed supine, without the head or any extremities dangling over the edge of the table. Measurement of ankle blood pressures in a seated position will
Subclavian artery its lateral side are the upper trunks of the brachial plexus and the Omohyoideus. Below, it rests on the upper surface of the first rib. Embryologically, the left subclavian simply arises from the left 7th intersegmental artery, while the right subclavian arises, proximal to distal: Essentially, the 4th aortic arch and dorsal aorta form the aortic arch on the left, but since the right dorsal aorta regresses distal to the right 7th intersegmental artery, on the left they form the proximal portion of the subclavian artery. Since the left subclavian is then a tributary of the left common carotid, they