what is the instrument used to measure blood pressure

The instrument used to measure blood pressure is called a sphygmomanometer, which is also known as a blood pressure cuff. It consists of three parts: a cuff that can be inflated with air, a pressure meter (manometer) for measuring air pressure in the cuff, and a stethoscope for listening to the sound the blood makes as it flows through the brachial artery (the major artery found in your upper arm) . The cuff is wrapped around the upper arm and inflated to stop the flow of blood in the artery. As the cuff is slowly deflated, a healthcare practitioner uses a stethoscope to listen to the blood pumping through the artery. These pumping sounds register on a gauge attached to the cuff. The first pumping sound the practitioner hears is recorded as the systolic pressure, and the last sound is the diastolic pressure. Digital blood pressure monitors are also available for automated readings, but they can sometimes be inaccurate and produce unreliable readings, especially in people with certain heart rhythm problems or arteries that have hardened due to arteriosclerosis.