To measure blood pressure, your doctor uses an instrument call a sphygmomanometer, which is more often referred to as a blood pressure cuff. The cuff is wrapped around your upper arm and inflated to stop the flow of blood in your artery. As the cuff is slowly deflated, your doctor uses a stethoscope to listen to the blood pumping through the artery. These pumping sounds register on a gauge attached to the cuff. The first pumping sound your doctor hears is recorded as the systolic pressure, and the last sound is the diastolic pressure.
Update Date 6/23/2012
Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Michael A. Chen, MD, PhD, Assistant Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.