Measuring the Systolic blood pressure with an ABI machine is simple and requires blood pressure cuffs and a sensor.
Once a blood pressure cuff is wrapped around the measured site, a distal Doppler waveform is obtained. The cuff is then inflated until the distal signal disappears as a result of the total occlusion. The blood pressure cuff is then deflated in a controlled manner, and the pressure at which the distal signal re-appears is determined as the systolic pressure.
An extension to the basic ABI test is the complete non-invasive physiologic studies of lower extremity arteries. It includes placing cuffs not only on the Ankles but also on other segments of the legs. This type of test is detailed in the Segmental Blood Pressures section.
Another important extension is performing ABI before and after an induced stress activity such as walking, treadmill, and tiptoes. This type of test is detailed in the Exercise Stress Test section.