The Ankle-Brachial Index is used to identify the presence of:

• A. A measure of oxygen saturation in blood
• B. Identify presence of impaired arterial blood flow (ischemia)
• C. Measure blood glucose levels
• D. Assess venous insufficiency

Answer: (B)

The Ankle-Brachial Index assesses arterial blood flow to the legs by comparing ankle and arm systolic pressures. This ratio helps detect peripheral arterial disease, where narrowed or blocked arteries reduce blood delivery to the legs, indicating possible ischemia. A lower than normal ABI points to impaired arterial perfusion and elevated risk of symptoms like claudication and ulcers. It’s not a measure of oxygen saturation, glucose, or venous drainage, which are assessed by different tests.