For accurate measurement of blood pressure, where should the cuff be placed relative to the heart?

• A. The cuff should be at head level.
• B. The cuff should be at heart level; the arm should be supported and relaxed.
• C. The cuff should be placed below the heart with the arm extended.
• D. The cuff height is not important as long as the patient is calm.

Answer: (B)

Accurate blood pressure relies on measuring arterial pressure at the same height as the heart. Keeping the cuff at heart level avoids gravity-related distortions in the reading. If the cuff is higher than the heart, the reading tends to be falsely low; if it’s lower than the heart, the reading tends to be falsely high. At the same time, the arm should be supported and relaxed to prevent muscle tension from elevating the reading. So, place the cuff on the arm at heart level with the arm supported and relaxed, typically with the patient seated, back supported, feet uncrossed and flat, and the forearm resting on a table.