Measuring Blood Pressure • Blood pressure is indicates your heart health • It is determined by the contractions of the heart • Your pressure varies depending on the condition of your heart and blood vessels • Pressure is measured in millimeters of mercury (mm Hg)
What is Blood Pressure • Blood pressure is the force that blood exerts against blood vessel walls. • The pumping action of the heart generates the flow • Pressure occurs when the flow is met by resistance from blood vessel walls
Laminar Flow • Blood flows faster in the center of a blood vessel, because the blood near the sides are hitting the walls of the vessels. • Is caused by the friction (resistance) between the blood and the vessel walls.
Blood Pressure Graph Pulse Pressure • By taking your pulse, you can feel that blood pressure fluctuation with each heartbeat. • The pulse which you feel is actually a pressure wave that travels from your heart though your arteries Dicrotic Notch Average Pressure Diastolic Systolic
Systolic Pressure • Systolic pressure is the maximum pressure exerted by the blood against the artery walls. • It results when the ventricles contract. • Normally, it measures 120 mm Hg. Systolic
Dicrotic Notch • The Dicrotic Notch represents the interruption of blood flow due to the brief backflow of blood that closes the aortic semilunar valve when the ventricles relax. Dicrotic Notch
Diastolic Pressure • Diastolic Pressure is the lowest pressure in the artery. • It result when the ventricles are relaxed and is usually around 80 mm Hg. Diastolic
Blood Pressure Sounds • A cuff is inflated to constrict an artery so that no blood flows. • As the cuff pressure is slowly released, but the artery is still partially constricted, blood flow begins again. • Sounds can be heard because the blood flows violently causing audible sounds. • When the artery is fully open, the blood flows freely and the sounds disappear.
Checking Blood Pressure • The first sounds that are heard indicate systolic pressure (top number). • When the sounds stop, diastolic pressure has been reached (bottom number). • Average blood pressure is: 120 80