Blood Pressure and Baroreceptor Reflex

The ability of arterioles to control blood distribution and blood pressure.

The force exerted by blood against the walls of blood vessels, specifically arteries.

The pressure within capillaries is lower than in arterioles because of the high resistance of arterioles, restricting blood flow.

Capillaries have a large total cross-sectional area, which helps to reduce blood pressure.

Blood pressure is primarily controlled by heart rate (HR), stroke volume (SV), and peripheral resistance.

Increased sympathoadrenal activity raises blood pressure by constricting arterioles and increasing cardiac output.

The kidney plays a crucial role in blood pressure regulation by controlling blood volume, which affects stroke volume.

A reflex mechanism that helps regulate blood pressure by detecting changes in blood pressure and adjusting heart rate and blood vessel diameter.

Stretch receptors located in the aortic arch and carotid sinuses that detect changes in blood pressure.

An increase in blood pressure stretches the walls of the aortic arch and carotid sinuses, increasing the frequency of action potentials sent to the vasomotor and cardiac control centers in the medulla.

The baroreceptor reflex is most sensitive to decreases and sudden changes in blood pressure.

Stretch receptors in the atria that are activated by increased venous return, promoting a decrease in blood pressure.

Increased venous return triggers reflex tachycardia (increased heart rate) and inhibition of Antidiuretic hormone (ADH) release to reduce blood pressure.

Atrial natriuretic peptide (ANP) is a hormone released by the atria in response to atrial stretch, promoting excretion of sodium and water to reduce blood pressure.

The measurement of blood pressure using a sphygmomanometer and stethoscope to listen for Korotkoff sounds.

The absence of sound during laminar flow, indicating normal, silent, smooth blood flow.

Sounds heard during the measurement of blood pressure when the sphygmomanometer cuff pressure is higher than diastolic but lower than systolic pressure.

The first Korotkoff sound is heard at the pressure where blood first passes through the cuff constricting the artery, creating turbulent flow.

The last Korotkoff sound is heard when the cuff pressure equals diastolic pressure, because the sounds disappear when blood flow becomes laminar again.

The blood pressure cuff is inflated above systolic pressure, blocking the artery.

As the cuff pressure is lowered, blood flows through the artery only when systolic pressure exceeds cuff pressure, generating Korotkoff sounds.

When cuff pressure equals diastolic pressure, blood flows smoothly again, eliminating Korotkoff sounds.

The difference between systolic pressure and diastolic pressure.

The average arterial pressure during the cardiac cycle, calculated by diastolic pressure + 1/3 pulse pressure.

The diastole phase is longer than the systole phase, impacting the calculation of mean arterial pressure.

Diastolic pressure + 1/3 pulse pressure is used to approximate mean arterial pressure because diastole is longer than systole.