What is the medical device commonly used to measure blood pressure?

The sphygmomanometer is the medical device that is specifically designed to measure blood pressure. It typically consists of an inflatable cuff that encompasses the arm, a measuring unit that displays the pressure, and often includes a bulb for inflation. When the cuff is inflated, it blocks the flow of blood; as the cuff deflates, the clinician listens with a stethoscope for the return of blood flow, which marks the systolic and diastolic pressure readings.

In contrast, the electrocardiogram tracks the electrical activity of the heart, the stethoscope is primarily used for auscultation to listen to internal body sounds including heartbeats and respiratory sounds, and the pulse oximeter is employed to measure the oxygen saturation level in the blood. These devices serve different diagnostic purposes and are not intended for direct measurement of blood pressure, which is why the sphygmomanometer is the correct choice.