Tuesday, June 4, 2024

guiding question week 8

 BBlood vessels, hemodynamics & pressure

    Describe the anatomy of a general blood vessel.

What are the functions of each of the layers?
        Describe the characteristics and functions of arteries, arterioles, capillaries (all three types), venules and veins.


        Explain how the elastic recoil of arteries contributes to maintaining blood flow.

    Give a general description of how exchange happens in capillaries.

 How does that exchange work differently in continuous capillaries, fenestrated capillaries and discontinuous capillaries?
        What is exchange by bulk flow and how is it different than exchange by diffusion?
        Differentiate between reabsorption and filtration.
        Describe the following pressures, what causes them, and whether they favor filtration or reabsorption: Blood hydrostatic pressure, interstitial fluid osmotic pressure, blood colloid osmotic pressure, and net filtration pressure.
        Describe the process of exchange across a capillary as it relates to the three pressures mentioned in the question above. How does exchange differ at the arterial end of a capillary vs. the venous end?
    What factors affect blood pressure?
        Define blood pressure, pulse, pulse pressure, mean arterial pressure
        and peripheral resistance
        Give the ranges for a healthy diastolic and systolic blood pressure.
    How does cardiac output (or stroke volume x HR) affect MAP?
        How does total peripheral resistance affect MAP?
        What are the three factors that contribute to total peripheral resistance? Which of these is altered most easily and most often to affect MAP?
        How is total peripheral resistance altered systemically? (think about sympathetic vs parasympathetic responses) Be sure to talk about what
        neurotransmitters/receptors and/or hormones are involved*
        Describe active hyperemia (excess of blood in vessels supplying oxygen to organs). When does this process take place? What are the stimuli for vasodilation.
    What are baroreceptors and where are they found?
        How do blood pressure changes alter the number of action potentials sent to the cardiovascular control center?
        List the four effectors (and the autonomic nervous system receptors) of the cardiovascular control center*
        Draw a flow chart diagraming the systemic response to increased blood pressure*
        Draw a flow chart diagraming the systemic response to decreased blood pressure*
    How do changes in blood volume alter stroke volume? Cardiac output? MAP?
        How does the body compensate for low blood volume?
    What is hypertension? What are the dangers of hypertension?
        Explain how atherosclerosis develops and the dangers it presents.
        List several treatments for high blood pressure and delineate their mechanisms of action*
    Be familiar with the equations we discussed in class including how to calculate NFP, cardiac output, and MAP.
        The other equations provided were to summarize concepts we have already talked about all throughout this class (factors that impact resistance and blood pressure, conceptually what determines stroke volume, etc.). If the equations work for you as a quick reference, use them. If they don't, then go with the analogies we discussed throughout class (thick vs thin straws/pinched or unpiched hoses, milkshake vs. soda as fluid, etc.).

 

Note 1: Total peripheral resistance (TPR) is also called systemic vascular resistance (SVR). I thought I'd let you know in case you are using other resources to study!




week 8



 

Week 8 Guided Questions

 Week 8 Guided Questions

Blood vessels, hemodynamics & pressure

Describe the anatomy of a general blood vessel. What are the functions of each of the layers?

Describe the characteristics and functions of arteries, arterioles, capillaries (all three types), venules and veins.

Explain how the elastic recoil of arteries contributes to maintaining blood flow.

Give a general description of how exchange happens in capillaries. How does that exchange work differently in continuous capillaries, fenestrated capillaries and discontinuous capillaries?

What is exchange by bulk flow and how is it different than exchange by diffusion?

Differentiate between reabsorption and filtration.

Describe the following pressures, what causes them, and whether they favor filtration or reabsorption: Blood hydrostatic pressure, interstitial fluid osmotic pressure, blood colloid osmotic pressure, and net filtration pressure.

Describe the process of exchange across a capillary as it relates to the three pressures mentioned in the question above. How does exchange differ at the arterial end of a capillary vs. the venous end?

What factors affect blood pressure?

Define blood pressure, pulse, pulse pressure, mean arterial pressure

and peripheral resistance

Give the ranges for a healthy diastolic and systolic blood pressure.

How does cardiac output (or stroke volume x HR) affect MAP?

The mean arterial pressure (MAP) is influenced by both cardiac output (CO) and systemic vascular resistance (SVR). Here’s how they relate:


Cardiac Output (CO): CO represents the volume of blood pumped by the heart per minute. When CO increases, MAP tends to rise as well. Conversely, if CO decreases, MAP may decrease.

Systemic Vascular Resistance (SVR): SVR refers to the resistance encountered by blood flow in the systemic circulation. An increase in SVR leads to higher MAP, assuming CO remains constant.

In summary, changes in either CO or SVR affect MAP. If CO and SVR change proportionately (e.g., CO doubles while SVR decreases by half), MAP remains relatively stable. However, alterations in either factor can impact MAP1. Keep in mind that MAP is a critical parameter for assessing cardiovascular health, with values below 90 mmHg considered low risk and values above 96 mmHg indicating stage one hypertension2. 

How does total peripheral resistance affect MAP?

What are the three factors that contribute to total peripheral resistance? Which of these is altered most easily and most often to affect MAP?

How is total peripheral resistance altered systemically? (think about sympathetic vs parasympathetic responses) Be sure to talk about what

neurotransmitters/receptors and/or hormones are involved*

Describe active hyperemia (excess of blood in vessels supplying oxygen to organs). When does this process take place? What are the stimuli for vasodilation.

What are baroreceptors and where are they found?

How do blood pressure changes alter the number of action potentials sent to the cardiovascular control center?

List the four effectors (and the autonomic nervous system receptors) of the cardiovascular control center*

Draw a flow chart diagraming the systemic response to increased blood pressure*

Draw a flow chart diagraming the systemic response to decreased blood pressure*

How do changes in blood volume alter stroke volume? Cardiac output? MAP?

How does the body compensate for low blood volume?

What is hypertension? What are the dangers of hypertension?

Explain how atherosclerosis develops and the dangers it presents.

List several treatments for high blood pressure and delineate their mechanisms of action*

Be familiar with the equations we discussed in class including how to calculate NFP, cardiac output, and MAP.

The other equations provided were to summarize concepts we have already talked about all throughout this class (factors that impact resistance and blood pressure, conceptually what determines stroke volume, etc.). If the equations work for you as a quick reference, use them. If they don't, then go with the analogies we discussed throughout class (thick vs thin straws/pinched or unpiched hoses, milkshake vs. soda as fluid, etc.).

 

ECG reading


 SA Mode 60-100 per minute 

AV node generate its own impulse 40-60 per minute 

Bundle of hist 

EKG 

P wave represents Atrial Depolarization 

QRS complex ventricular depolarization 

Ventricular depolarization 

every contraction follow by depolarization 


T wave