Hemodynamics Flashcards
What is vasculature?
the blood vessels of the body
What is a circuit?
a network of blood vessels that begins and ends at the heart
what circuits are the vasculature divided into?
pulmonary and systemic circuit
What does the pulmonary circuit contain?
the blood vessels within the lungs, and those that transport blood bw the heart and lungs
what does the systemic circuit contain?
blood vessels within all other organs, and those that transport blood between the heart and those organs
What is series flow?
the movement of blood thru different types of blood vessels in sequence
what are the 5 types of blood vessels?
arteries, arterioles, capillaries, venules, veins
what is parallel flow?
movement of blood thru different organs at the same time
What is blood flow?
the rate at which blood moves thru the vasculature
what does blood flow measure?
the efficiency of blood movement to and from the tissues
what are the determinants of blood flow?
pressure difference and vascular resistance
What is pressure difference?
the force that drives blood thru the circuits
What ventricle drives the blood thru the pulmonary circuit?
right ventricle
What ventricle drives the blood through the systemic circuit?
left ventricle
what are the units of pressure difference?
mmHg or kPa
what does pressure difference calculation rely on?
mean arterial pressure (MAP)
how does blood pressure vary during the cardiac cycle?
high during systole, low during diastole
does the pressure difference vary between circuits? How so?
yes, pulmonary circuit is usually 15mmHg and 95 mmHg in the systemic circuit
what is vascular resistance?
an impediment to blood flow; a measure of how much friction is encountered by blood as it moves thru the vasculature
what are the 3 determinants of resistance in a single blood vessel?
length, radius of blood vessel, viscosity of blood
what is blood viscosity affected by? what is it and what is its relationship with viscosity?
hematocrit; the percent of blood vol occupied by red blood cells; as hematocrit increases so does viscosity
what factors increase resistance? decrease resistance?
increases with increasing length and viscosity; decreases with increasing radius
what causes blood flow to increase and decrease?
increases with increased pressure difference and radius; decreased with increasing length and viscosity
changes in radius have what kind of effect on flow? what does that mean?
disproportionate; small changes in radius will have a large effect on flow
