blood pressure (redirected from blood pressure classification)

blood pressure

n.

Abbr. BP The pressure exerted by the blood against the walls of the arteries, maintained by the contraction of the left ventricle, the resistance of the arterioles and capillaries, the elasticity of the arterial walls, and by the viscosity and volume of the blood. Also called arteriotony.

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blood pressure,

n force applied by circulating blood on the walls of the blood vessels and on the chambers of the heart. The pressure in a healthy individual varies but is usually considered below 120 mm Hg during systole and 80 mm Hg during diastole in adults.

Blood pressure.

Category	Systolic (mm Hg)		Diastolic (mm Hg)
Optimal†	<120		<80
Normal	<130		<85
High normal	130–139		85–89
Hypertension‡
Stage 1 (mild)	140–159	or	90–99
Stage 2 (moderate)	160–179	or	100–109
Stage 3 (severe)	≥180	or	≥110

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blood pressure,

n the pressure exerted on the arterial walls by the blood when the heart is in systole (systolic pressure), and the pressure maintained by the elasticity of the arteries when the heart is in diastole (diastolic pressure). A consistent arterial pressure greater than 120 over 80 is considered high and suggestive of hypertensive vascular disease. See also hypertension, systole, diastole.

blood pressure classification,

n the rating system for blood pressure levels in millimeters of mercury (mm Hg), given as the systolic over the diastolic pressure. Both the systolic and diastolic pressure, if at increased levels, are indicators of concern for cardiovascular problems. Normal is less than 120 over 80; prehypertension is 120-139 over 80-89, stage 1 hypertension is 140-159 over 90-99; stage 2 hypertension is 159 or higher over 99 or higher. See also hypertension.

blood pressure, diastolic,

n the pressure in the bloodstream when the heart relaxes and dilates, filling with blood. See also blood pressure; blood, pressure, stages; and diastole.

blood pressure, systolic,

n the pressure exerted on the bloodstream by the heart when it contracts, forcing blood from the ventricles of the heart into the pulmonary artery and the aorta. See also blood pressure; blood, pressure, stages; and systole.

blood pressure cuff,

n a part of a sphygmomanometer that fits over the patient's arm. It comes in four sizes, for children up to obese adults. It should be made of a nonelastic material, and the cuff used should be about 20% bigger than the arm it fits over–an undersized cuff will cause the blood pressure reading to appear higher than it is in reality, whereas an oversized cuff will cause the reading to appear too low.

blood pressure stages,

n any of the three stages of hypertension marked by elevated blood pressure. Stage I is 140-159 over 90-99; Stage II is 160-179 over 100-109; Stage III is 180-209 over 110-119.

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blood pressure

the pressure of the blood in the blood vessels. The term usually refers to the pressure of the blood within the arteries, or arterial blood pressure. This pressure is determined by several interrelated factors, including the pumping action of the heart, the resistance to the flow of blood in the arterioles, the elasticity of the walls of the main arteries, the blood volume and extracellular fluid volume, and the blood's viscosity, or thickness.

Relatively simple Doppler instruments can provide accurate blood pressure measurements in dogs and cats. The systolic pressure in dogs is 132±22 mmHg; in cats it is 108±23 mmHg. Thoroughbreds have been shown to be 112/77 mmHg. Indwelling catheters can be used in dogs to monitor central venous pressure.

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arterial blood pressure

the common measure of blood pressure. The measurement in animal patients must be by a method that does not require entrance to an artery, i.e. noninvasive. Standard methods use an inflatable cuff around a limb, around the tail in the horse, and measurement of the air pressure required to obliterate the pulse wave—the systolic blood pressure, and permit the re-entry of the pulse wave—the diastolic blood pressure.

blood pressure homeostasis

the maintenance of a steady state of blood pressure. The mechanisms involved include the baroreceptor mechanism, the chemoreceptor mechanism, the ischemic response of the central nervous system (the Cushing response), the renin-angiotensin vasoconstrictor and the renin-angiotensin-aldosterone system, the capillary fluid-shift mechanism, the regulation of body fluid level by the kidney and the stress-relaxation mechanism of the arterial wall.

blood pressure impedance

the resistance to pulsatile flow, as in arteries.

pulmonary wedge blood pressure

see wedge pressure.

blood pressure regulation

the complex regulatory system which controls arterial blood pressure is dependent on sensory inputs related to cardiac output, peripheral resistance to blood flow at the arterioles, the viscosity of the blood, the volume of blood in the arterial system, the elasticity of the arterial walls. Changes in blood pressure are brought about by the control exerted on the same physiological mechanisms.

venous blood pressure

see central venous pressure.