Blood Pressure

The pressure exerted by circulating blood upon walls of blood vessels is blocked pressure. Blood pressure is one of the vital signs. Blood pressure usually refers to the arterial pressure of the systemic circulation. Blood pressure varies between a maximum and minimum pressure during each heartbeat. The mean blood pressure decreases as the circulating blood moves away from the heart through arteries.  This is the result of the blood pumped by the heart and the resistance to flow in blood vessels. Blood pressure continues to decrease as the blood moves through the capillaries and back to the heart through veins and drops most rapidly along the small arteries and arterioles. Some influences on blood pressure at various places in the body include gravity, valves in veins, and pumping from contraction of skeletal muscles.

Blood pressure measurements without further specification usually refers to the systemic arterial pressure measured at a person’s upper arm. The brachial artery on the inside of an elbow is where it is measured. This is the upper arms major blood vessel that carries blood away from the heart. Blood pressure is often expressed in terms of the systolic pressure over diastolic pressure.