arterial blood pressure

(noun)

The pressure of the blood within an arterial vessel, typically the brachial artery in the upper arm. Calculated over a cardiac cycle and determined by the cardiac output (CO), systemic vascular resistance (SVR), and central venous pressure (CVP). It can be approximately determined from measurements of the systolic pressure and the diastolic pressure while there is a normal resting heart rate.

Related Terms

Examples of arterial blood pressure in the following topics:

  • Extremes in Blood Pressure

    • Chronically elevated blood pressure is called hypertension, while chronically low blood pressure is called hypotension.
    • Hypertension or high blood pressure, sometimes called arterial hypertension, is a chronic medical condition in which the blood pressure in the arteries is elevated above 140/90 mmHg.
    • Even moderate elevation of arterial blood pressure is associated with a shortened life expectancy.
    • Hypotension is a medical condition in which the blood pressure in the arteries is reduced below 100/60 mmHg.
    • However, blood pressure is considered too low only if noticeable symptoms are present.

  • Arterial Blood Pressure

    • The measurement of blood pressure without further specification usually refers to systemic arterial pressure measured at the upper arm.
    • The measurement of blood pressure without further specification usually refers to the systemic arterial pressure, defined as the pressure exerted by circulating blood upon the walls of blood vessels.
    • Pressure is typically measured with a blood pressure cuff (sphygmomanometer) wrapped around a person's upper arm, which measures the pressure in the brachial artery.
    • Blood pressure in the arteries is much higher than in the veins, in part due to receiving blood from the heart after contraction, but also due to their contractile capacity.
    • All levels of arterial pressure put mechanical stress on the arterial walls.

  • Artery Function

    • Arteries are high-pressure blood vessels that carry oxygenated blood away from the heart to all other tissues and organs.
    • Arteries are blood vessels that carry blood away from the heart under pressure.
    • This blood is usually oxygenated, with the exception of that in the pulmonary artery, which carries deoxygenated blood to the lungs.
    • In arteries, the tunica media, which contains smooth muscle cells and elastic tissue, is thicker than that of veins so it can modulate vessel caliber and thus control and maintain blood pressure.
    • The pressure in the arterial system decreases steadily, highest in the aorta and lowest in the venous system, as blood approaches the heart after delivery of oxygen to tissues in the systemic circulation.

  • Measuring Blood Pressure

    • Blood pressure is the pressure blood exerts on the arterial walls.
    • Usually the blood pressure is read from the left arm, although blood pressures are also taken at other locations along the extremities.
    • These pressures, called segmental blood pressures, are used to evaluate blockage or arterial occlusion in a limb (for example, the ankle brachial pressure index).The difference between the systolic and diastolic pressure is called the pulse pressure.
    • A blood pressure cuff and associated monitor used for determining systolic and diastolic pressures within an artery.
    • Explain how blood pressure is measured and the ranges of blood pressure readings

  • Hypertension

    • Hypertension (HTN) or high blood pressure, sometimes called arterial hypertension, is a chronic medical condition in which the blood pressure in the arteries is elevated.
    • High blood pressure is said to be present if it is persistently at or above 140/90 mmHg.
    • The repercussions of chronically elevated blood pressure included widespread damage to the circulatory system, arterial disease, cardiac failure and even neurological impairments
    • Even moderate elevation of arterial blood pressure is associated with a shortened life expectancy.
    • Persistant high blood pressure can affect many areas of the body.

  • Introduction to Blood Pressure

    • Blood pressure is a vital sign reflecting the pressure exerted on blood vessels when blood is forced out of the heart during contraction.
    • Blood pressure is the pressure that blood exerts on the wall of the blood vessels.
    • Blood pressure is one of the principal vital signs.
    • Mean blood pressure decreases as circulating blood moves away from the heart through arteries, capillaries, and veins due to viscous loss of energy.
    • Mean blood pressure decreases during circulation, although most of this decrease occurs along the small arteries and arterioles.

  • Distribution of Blood

    • Humans have a closed cardiovascular system, meaning that blood never leaves the network of arteries, veins, and capillaries.
    • On a larger level, vasoconstriction is one mechanism by which the body regulates and maintains mean arterial pressure.
    • Generalized vasoconstriction usually results in an increase in systemic blood pressure, but it may also occur in specific tissues, causing a localized reduction in blood flow.
    • Therefore, dilation of arterial blood vessels (mainly the arterioles) causes a decrease in blood pressure.
    • Oxygenated arterial blood (red) and deoxygenated venous blood (blue) are distributed around the body.

  • Great Vessels of the Heart

    • The aorta is a highly elastic artery and is able to dilate and constrict in response to blood pressure and volume.
    • The difference in pressure between the aorta and right atrium accounts for blood flow in the circulation, as blood flows from areas of high pressure to areas of low pressure.
    • The aortic arch contains peripheral baroreceptors (pressure sensors) and chemoreceptors (chemical sensors) that relay information concerning blood pressure, blood pH, and carbon dioxide levels to the medulla oblongata of the brain.
    • This part of the aorta is vulnerable to bursting and hemorrhage (aneurysm) from persistently high blood pressure.
    • These are the only arteries that carry deoxygenated blood, and are considered arteries because they carry blood away from the heart.

  • Elastic Arteries

    • Elastic arteries include the largest arteries in the body, those closest to the heart, and give rise to the smaller muscular arteries.
    • Arterial elasticity gives rise to the Windkessel effect, which through passive contraction after expansion helps to maintain a relatively constant pressure in the arteries despite the pulsating nature of the blood flow from the heart.
    • Due to position as the first part of the systemic circulatory system closest to the heart and the resultant high pressures it will experience, the aorta is perhaps the most elastic artery, featuring an incredibly thick tunica media rich in elastic filaments.
    • When the left ventricle contracts to force blood into the aorta, the aorta expands.
    • This stretching generates the potential energy that will help maintain blood pressure during diastole, when the aorta contracts passively.

  • Operation of Semilunar Valves

    • The semilunar valves allow blood to be pumped into the major arteries, but prevent backflow of blood from the arteries into the ventricles.
    • These valves allow blood to be pumped into the arteries, but prevent backflow of blood from the arteries into the ventricles.
    • When the atrioventricular valves shut, the semilunar valves open, forcing blood into the aorta and pulmonary artery.
    • When the pressure in the left ventricle exceeds the pressure in the aorta, the aortic valve opens, and blood flows from the left ventricle into the aorta.
    • When ventricular systole ends, pressure in the right ventricle drops rapidly, and the pressure in the pulmonary artery forces the pulmonary valve to close.