Final answer:
The tourniquet cuff is placed around the patient's arm level with the heart, and its position enables accurate blood pressure measurement using a sphygmomanometer.
Step-by-step explanation:
The placement of the tourniquet cuff is determined by the anatomic structure of the patient's arm and is generally placed around the patient's arm at about the level of the heart. This placement allows for accurate measurement of blood pressure, as it reflects the pressure in the large arteries that are at the same level as the heart when a person is sitting or standing. A clinician wraps the inflatable cuff tightly around the arm and uses a sphygmomanometer, which may be attached to a mercury-filled manometer or a diaphragm gauge to measure pressure. The cuff is inflated by squeezing a rubber pump, which raises pressure around the artery and temporarily blocks blood flow into the arm. After the cuff is inflated, the clinician then places a stethoscope in the antecubital region—just below the cuff—to listen for the Korotkoff sounds that indicate blood pressure levels.