What instrument is used to measure blood pressure?

The sphygmomanometer is the instrument specifically designed to measure blood pressure. It consists of an inflatable cuff that is placed around the patient's arm and a gauge that displays the pressure readings. When the cuff is inflated, it temporarily stops blood flow in the artery. The pressure is then gradually released, and the point at which blood flow resumes is noted as the systolic pressure (the top number), while the point at which blood flow is completely restored is noted as the diastolic pressure (the bottom number). This method allows healthcare providers to accurately assess a patient's blood pressure, which is crucial for diagnosing and monitoring conditions such as hypertension.

In contrast, the stethoscope is primarily used for auscultation; it allows providers to listen to internal sounds of the body, such as the heart and lungs. While it is often used in conjunction with the sphygmomanometer during blood pressure measurements, it does not measure blood pressure itself. A thermometer is used to measure body temperature, and a pulse oximeter measures the oxygen saturation level in the blood. Each of these instruments serves a specific purpose in the clinical setting, but only the sphygmomanometer is designed for blood pressure measurement.