Vascular Doppler measures the amount of blood flow through arteries and veins using high-frequency sound waves. Such measurements, known as vascular flow studies or blood flow studies, help detect abnormal blood flow within an artery or a vein. Doppler machines are usually used to assess blood vessels that supply blood to arms and legs. Abnormal values in these vessels indicate a diagnosis of peripheral arterial disease (PAD), mostly in patients with diabetes.
Kody Medical Electronics offers handheld vascular Doppler machines that help assess ankle brachial index (ABI), a parameter that indicates the severity of PAD. It is useful in the diagnosis of PAD and aids in improving patient outcomes.
Calculation of Ankle-Brachial Index
The first step in arriving at the ABI is to measure the blood pressure in both ankles of the patient using a handheld vascular Doppler. Then the higher of the two systolic (upper number) blood pressures from the two ankle arteries is divided by the higher systolic blood pressure from the two arm readings. Some people use an average of each pair of readings instead of the higher number.
Low Ankle-Brachial Index
An ABI value of 0.9 or lower is indicative of PAD. Low ABI points to a higher risk of
· heart attack
· kidney disease
· high blood pressure
If the ABI value is a little low despite the presence of symptoms of PAD, the ABI may be repeated after a walk on a treadmill. A decrease of 20% or more after exercising is considered an abnormal value.
High Ankle-Brachial Index
An ABI value higher than 1.4 is indicative of stiffness of peripheral blood vessels because of advanced age or diabetes. Researchers have found that people with an ABI higher than 1.4 carry twice the risk of cardiovascular death.
ABI and Patient Outcome
ABI is a very good indicator of PAD, especially in patients with diabetes. Early diagnosis of PAD results in early intervention and better patient outcomes. Frequent repetitions of ABI testing with handheld vascular Doppler in those who are positive for PAD helps in assessing the status of the disease and subsequently modifying the treatment strategies as required.
Kodys handheld vascular Doppler machines, which are bidirectional, provide the best method to assess for PAD and facilitate early medical intervention to improve patient outcomes significantly.