pk Flashcards
How are the systemic and pulmonary circulation linked?
In series
How is the systemic circulation and the arterial circuts connected?
In parallel
What is the blood volume called in veins? Arteries?
veins: Unstressed volume
(bc it isn’t under high stress)
Arteries Stressed volume (bc it is under high stress)
What is laminar flow? What layer is the fastest?
The flow of blood in layers
Fastest: In the center and immobile at the walls
What is turbulent flow?
When velocity is high and blood flows through a narrow opening (مطبات هوائية)
What does turbulence do to resistance to flow?
Increases it
(makes sense like flying smoothly in an airplane then turbulence all of a sudden)
What are cardiac murmurs and bruits?
cardiac murmurs: Sounds of turbulent flow through valves or backflow (remember ossculation)
bruits: Turbulent flow in periphral arteries due to atherosclerotic plaque or narrowed large arteries
What does Reynolds number predict? What is the formula?
Turbulence in blood flow
Formula: Re = pDV/n
ρ density of fluid
D diameter of the tube
V is velocity flow
η is viscosity of the fluid.
(Remember renold regins)
What is the law of laplace?
T= (pi-po) x r
Po= pressure compressing the vessel (bc initally it is compressed)
Pi= pressure streching the vessel (bc finally it is streched)
(The palace gets a lot of attention and it has a large radius and atmospheric pressure acts on it and a lot of people are inside so pi)
What is the law of laplace in spherical vessels?
T=p x r/2
(bc s looks like 2)
(bc the palace is big and long, not just big)
What is the formula for wall stress? (σ)
(σ) = Pxr/wt
wt= wall thickness
What is aneurysm?
The weaking of the wall of blood vessel and increasing in radius, which thins out the walls, which causes more tension and stress.
What is the difference between the Flow rate and Velocity?
Flow rate How much blood is flowing at a certain time.
Velocity How fast the blood is flowing
What is the formula for velocity and flow rate?
V= Flow rate/ cross-sectional area
Q= Volume/time
what is the equation for Flow rate (Q) with resistance and pressure gradient? What is another name for flow rate in this case?
Q= ΔP/R
ΔP=
Mean arterial pressure - Right arterial pressure
(Flow rate = Cardiac output)
What is the equation for mean cardiac output in systemic circulation?
…………………………………………………………………………
(MAP - right arterial pressure)/ Total periphral resistance
Map = Pressure in the aorta
Right arterial p = P2
TPR = Resistance caused by vasoconstriction or dilation
What is the Systemic and pulmonary pressure gradient formulas? ΔP
Systemic: arterial pressure – right atrial pressure
Pulmonary: Pulmonary arterial pressure – left atrial pressure
What is the formula for resistance to flow in both pulmonary and systemic circulations?
Systemic: 100 mmHg / CO
Pulmonary: 15 mmHg / CO
Which has higher resistance, pulmonary or systemic circulation? Why? What is the ratio of Systemic to pulmonary?
Higher: Systemic (bc it pumps blood to the entire body)
Ratio: 1/7
What is poiseuille’s law?
R = (8ηl) / (pi r^4)
η = viscosity of blood
l = length of blood vessel
r= radius of blood vessel
(like pause so and weird just like the formula)
What is poiseuille’s law flow formula?
F= ((Pa -Pb) x (π) x r^4)/ (8ηL)
What is the formula for resistance in parallel and series?
Parallel: 1/R = 1/R + 1/R..
Series: R = R + R + R……
