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KNOW THESE NORMAL PRESSURES:
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DRIVING PRESSURE (systemic circulation) = ?
MAP (Mean Arterial Pressure) which is the average of 120/80, or 100 mmHg
Why not RAP (Right Atrial Pressure)? Because it's nearly ZERO (look at RA in picture below)
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Normal pressure in the LEFT ATRIUM?
7mmHg
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Normal pressure in the RIGHT VENTRICLE?
25/0 mmHg
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Normal pressure in the LEFT VENTRICLE?
120/0 mmHg
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Normal pressure in the RIGHT ATRIUM?
-4 to 4 mmHg (it's returning deoxy blood from venous network of systemic circulation...comon!! it has to be at such a low pressure!)
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What's one of the essential, easiest way to see if a patient has a heart problem?
If they have any deviations from the normal pressures of the chambers!
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Systolic pressure is the pressure when the heart _________?
contracts! duh.
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Diastolic pressure is the pressure when the heart _________?
relaxes! comon! what is this grade school?
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Bulk flow says what?
That Blood Flow (F) = Difference in Pressure (P1-P2) over Resistance (R)

Pressure is our driving force, so it needs to be larger than our resistance to get flow.
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Systole occurs when? Be SPECIFIC!
- When the ventricular muscles are contracting, generating a circumferential tension in the ventrical walls, increasing pressure in the chamber.
- When ventricular pressure exceeds the pressure in the pulmonary artery (right pump) or aorta (left pump) blood is forced out of the chamber via the outlet valve.
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Increase in pressure?
Increase in resistence?
- Increase pressure = increase Flow
- Increase resistence = decrease flow
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Systemic Circulation Driving Pressure is = ?
The MAP (mean arterial pressure)
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Pulmonary Circulation Driving Pressure = ?
Mean Pulmonary Artery Pressure -- Left Atrial Pressure
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Pulmonary artery leave what ventricle?
The right venticle!
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Resistance is a force that _________ flow.
- opposes
- It is dependent upon the physical properties of vessels and blood
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What are the three factors that affect resistence (R) that opposes blood flow?
- Viscosity of the blood (n)
- Length of the vessel (L)
- Radius of the vessel (r) *** r is most imporant! it is inversely related to resistence--- the more you increase the radius of the BV the LOWER the Resistence will be because it's r4
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Which factor that affects the resistence of blood flow is most important?
- r4 = radius!
- very powerful, it is inversely related to the resistence, so if you increase the radius of a blood vessel you decrease the resistence
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Our SANS has second to second control of which of these components that affect resistence?
The radius, r --SANS has sec by sec control of the radius of our vessels
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Poiseuille-Hagan Equation

Increase in Pressure? = Flow?
Increase in Radius? = Flow?
Increase in Length? = Flow?
Increase in Viscosity (n)? =Flow?
- Incr P = Incr FLOW
- Incr r4 = Incr FLOW (double r, 16 fold increase in FLOW)
- Incr L = DECREASE FLOW*
- Incr Viscosity (n) = DECREASE FLOW*
*inversely related to flow
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Poiseuille-Hagan Equation?
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What is the most powerful indicator of flow?
RADIUS.
- because in the Poiseuille-Hagan Equation
- r4 will increase or decrease the flow by 16 fold.

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What is cardiac output (CO)?
The number of L per min that are flowing out of the heart
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Most of your Total Peripheral Resistence (TPR) is from what vessels?
the ARTERIOLES (the ones we contract)
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What is the most important equation of this ENTIRE BLOCK?
where your Mean Arterial Pressure (MAP) is equal to your Cardiac Output (CO, the number of L/min flowing out of heart) times your t otal peripheral resistence (TPR)
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Your MAP is =
MAP is your blood pressure AORTIC PRESSURE, which because your RAP (right atrial pressure) is basically zero, the driving pressure of your systemic circulation is your MAP.
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If Alberto Contador is blood doping, what negative effect could this have on his Blood Flow (F)?
- Break out the Poiseulle-Hagan Equation!
- He would increase the viscosity or n of the blood, and according to Poise's equation, viscosity is inversely related to the flow, so there would be a decrease the blood flow F. And he could have a heart attack and Lance would win naturally.

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When we listen for heart sounds (auscultate)what are we listening to?
- The turbulent flow of our heart valves, which is normal.

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How do you determine the resistence of vessels in series?
ADD the TOTAL resistence of each, EASY
Rtot = R1 + R2 + R3 + R4 + R5
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How do you determine the resistence of vessels in parallel?
R = 1/ 1/R1 + 1/R2 +1/ R3
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EQ for Pressure at a specific point?
P = F x R
*Remember when in a tube, must always subtract the pressure you calculate from the original pressure in the begining of the tube!!!
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The total resistence of a parallel system of vessels is always ______ than the resistance in a single vessel
- LOWER! Use this rule to check your math, total resistance should always be lower than a single resistance.

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Veins have a very high ______ which allows them to exhibit relatively large changes in blood volume, but smaller changes in pressure
VEINS = HIGH COMPLIANCE
- Veins are able to stetch (compliance) to high volumes and not exhibit a lot of pressure---so they don't have a high recoil force like arteries do
- Think of veins as your ZIP-LOCK baggies holding water, they hold a lot of blood but they don't exhibit and huge recoil force
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Arteries have a low ___________ which causes them to exhibit small changes in blood volume for a given pressure.
Arteries = low compliance
- Arteries want to snap back!
- They are the waterbaloons---they fill with blood and as a result want to snap back
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Static compliance is __________?
- the physical property of a vessel (a type of vascular compliance = stretchiness!)
- determined by amt. of CT present (changes with age and disease)
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Dynamic compliance is __________?
is the change in vascular tone due to smooth muscle contraction (altered second to second)
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Step 1 Related: What is a capacitance vessel?
- A vein!
- Veins act as "resevoirs"because they are 25% more compliant than your arteries
- This "resevoir" increases CO
- *Remember CO = MAP x TPR
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How do capacitance vessels increase CO?
capacitance vessels are veins remember**
- 1) Smooth Muscle surrounding veins is innverv by SANS
- 2) This stimulates contraction
- 3) Causes a decrease in venous compliance
- 4 )Vol. of bllod the veins can hold is reduced, displacing excess blood towards the heart! movin' it along!
- 5) Cardiac Output as a result is increased!!!
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The "Windkessel Effect" is a component of ______ compliance
Static!
It keeps blood moving during ventricular diastole (relaxation)
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What is the purpose of the Windkessel Effect?
To KEEP BLOOD MOVING during ventricular diastole
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MAP = ?
Normally around 100
MAP is the average arterial pressure during a single cardiac cycle
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Pulse pressure = ?
Pulse pressure is the difference between the systolic (relax) and diastolic (contraction) pressures
Pulse Pressure = Psys - Pdias
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