What is a sphygmomanometer used for?

A sphygmomanometer is specifically designed to measure blood pressure, which is the force exerted by circulating blood upon the walls of blood vessels. This device typically consists of a cuff that is inflated around the arm to temporarily constrict blood flow, which is then gradually released. As the cuff pressure decreases, specific sounds (Korotkoff sounds) can be heard through a stethoscope placed over the artery, allowing healthcare providers to determine the systolic and diastolic pressures.

In contrast, the other options pertain to different physiological measurements. For instance, measuring heart rate requires a different tool, such as a pulse oximeter or a heart rate monitor. Body temperature is usually taken with a thermometer, and respiratory rate is assessed through observation or specialized respiratory monitors. Thus, the unique function of the sphygmomanometer as a blood pressure measuring instrument distinguishes it clearly from the other choices.