Taking Blood Pressure

Q: When the nurse takes my blood pressure, I’m usually sitting on the exam table with my legs dangling down. I’ve heard the best way to get the most accurate blood pressure reading is when your feet are flat on the ground. Are there any other tips you can share about getting an accurate reading?

A: A number of factors can cause significant shifts in measured blood pressure. These include room temperature; recent exercise; alcohol or nicotine consumption; over-the-counter medications (especially for colds and flu); positioning of the arm, back, and legs; muscle tension; bladder distension; talking; and background noise.

To help get an accurate reading, you should sit comfortably in a chair, with your legs uncrossed, feet on the ground, and your back and arm supported. You should relax and avoid talking.

Ideally your blood pressure should be taken after five minutes of relaxation. Initially, a measurement should be taken from both arms. If one measurement is higher than the other, then that arm should be used to determine blood pressure. Future measurements should be made twice in the same arm.

Jennifer H. Mieres, M.D., is director of nuclear cardiology and associate professor of clinical medicine at New York University. She’s also a spokesperson for the American Heart Association.