Which instrument is used to measure blood pressure in a medical setting?

• A. Stethoscope
• B. Thermometer
• C. Otoscope
• D. Sphygmomanometer

Answer: (D)

Measuring blood pressure relies on a cuffed device that occludes the artery and provides a gauge reading. The instrument designed for this task is the sphygmomanometer. In manual measurements, the cuff is wrapped around the upper arm and inflated to stop blood flow, then deflated while a clinician uses a stethoscope to listen for the Korotkoff sounds; the pressures at which those sounds appear and disappear give the systolic and diastolic values. Modern automated devices still use the same cuff system but read the pressure electronically. The stethoscope is a listening tool used in conjunction with the sphygmomanometer for manual readings, not a standalone blood pressure instrument. A thermometer measures temperature, and an otoscope is for examining the ears. So the instrument used to measure blood pressure is the sphygmomanometer.