How does a spgymanometer works?

A sphygmomanometer measures blood pressure by utilizing an inflatable cuff that wraps around the upper arm. When the cuff is inflated, it occludes the blood flow in the artery; as the pressure is gradually released, a stethoscope is used to listen for the sounds of blood flow, known as Korotkoff sounds. The pressure at which these sounds first appear indicates the systolic blood pressure, while the pressure at which the sounds disappear indicates the diastolic pressure. The readings are typically displayed on a gauge or digital screen.