Lecture 28- Arterial Blood Pressure Flashcards
(28 cards)
What pressure is recorded as blood pressure?
Systemic arterial pressure
Cardiac output x systemic vascular resistance =
Blood pressure
Which valves are open during systole?
Semilunar
How does hyperthyroidism affect Bp
hypertension
What are short-term controls of BP
Baroreceptor reflexes
Chemoreceptor reflexes
Where are baroreceptors found?
carotid sinus
aortic arch
What does the arterial baroreflex respond to?
What does it do?
increased BP
Vagally decrease HR
Where are low pressure baroreceptors found?
What triggers them?
What do they do?
pulmonary arteries and right atrium
Low BP
Increases urine output to increase BV
What factors stimulate chemoreceptor reflex?
What does it do?
Decrease in O2, Increase CO2, Decrease in pH
Increases sympathetic tone- arterial pressure
What is the most important sympathetic receptor?
alpha1
What does each receptor do?
alpha1
alpha2
beta1
beta2
vasoconstriction
decrease release of NE
Increases SA node stimulation
vasodilation of skeletal muscle
what does inotropic mean?
increases contractility
What does chronotropic mean?
Increases rate
What does lusitropic mean?
increases relaxation speed
Where are alpha receptors found?
Skin, GI, kidneys
What is longterm control of BP
RAAS
Natriuretic peptides
ECF renal mechanism
What triggers renin release in the kidney?
Decreased BP in the kidney
What is the renin cascade?
Renin -> Angiotensinogen -> angiotensin I -> angiotensin II -> aldosterone from adrenal glands
What does angiotensin II cause
Release of aldosterone release
vasoconstriction
What is the function of aldoesterone?
Na/water retention at the level of the kidney tubules
What do ACE inhibitors do?
Stop angiotensin II
How does increased Na retention affect intravascular voolume?
increased volume
How does arterial pressure increase affect diuresis and natriuresis?
increase in urine output
increase in sodium excretion
How does an increase in ecf affect
CO
Atrial pressure
Renal water/Na loss
Increases all in a cascade
