Exam 1: 6 Feb 25 CV Phys And Thyroid

Question 1

What is the primary focus of Dr. Schmidt’s discussion?

Answer 1

The regulation of cardiac output and blood pressure during stress

Emphasizes the role of baroreceptors and the autonomic nervous system.

Question 2

What role do baroreceptors play in the body?

Answer 2

They help maintain blood pressure and cardiac output by responding to positional changes

Located in the carotid sinus and aortic arch.

Question 3

What neurotransmitters are involved in regulating blood pressure?

Answer 3

Norepinephrine and epinephrine

Norepinephrine is the main presser in the cardiovascular system.

Question 4

What is the significance of the renin-angiotensin-aldosterone axis?

Answer 4

It is crucial for blood pressure regulation

Involves compounds like vasopressin and aldosterone.

Question 5

Which circulatory beds are prioritized during stress?

Answer 5

• Coronary circulation
• Central nervous system
• Kidneys

The GI system is less prioritized during stress.

Question 6

What happens to blood flow in the GI system during stress?

Answer 6

Blood flow is diverted away from the GI system

The GI system can tolerate reduced perfusion for a while.

Question 7

What is the role of Atrial Natriuretic Peptide (ANP) and B-type Natriuretic Peptide (BNP)?

Answer 7

They help regulate blood volume by increasing urine output and reducing sodium retention

BNP levels can monitor heart failure treatment effectiveness.

Question 8

How does hemorrhage affect blood volume?

Answer 8

It decreases blood volume and plasma proteins

The body redistributes fluid to maintain plasma volume.

Question 9

What is the effect of intravenous fluid administration on cardiac output?

Answer 9

It can initially increase cardiac output and blood pressure

Stretch relaxation in large veins reduces venous pressure over time.

Question 10

What is the CNS ischemic response?

Answer 10

The strongest sympathetic nervous system response to low blood pressure

It can lead to tissue dysfunction and cell necrosis.

Question 11

What is cardiac reserve?

Answer 11

The maximum increase in cardiac output above normal levels

Factors affecting it include age, health, and valvular disease.

Question 12

What are common valve diseases affecting cardiac output?

Answer 12

• Aortic stenosis
• Aortic regurgitation

Congenital bicuspid aortic valves are more prone to stenosis.

Question 13

What is the function of digoxin in heart failure treatment?

Answer 13

It affects sodium-potassium ATPase pumps

Used as a last-resort drug, it can cause various side effects.

Question 14

Fill in the blank: The body has built-in systems to prevent _______ retention.

Answer 14

volume

Question 15

True or False: The kidneys increase urine output when there is increased atrial stretch.

Answer 15

True

Question 16

What is the impact of anesthesia on compensatory mechanisms?

Answer 16

Deeper anesthesia reduces compensatory capacity

Most compensatory mechanisms become less effective.

Question 17

What happens during reverse stretch relaxation?

Answer 17

Vein walls tighten during sympathetic nervous system engagement

The benefits of this response are not fully understood.

Question 18

How does increased blood volume affect circulation rate?

Answer 18

It typically lowers the circulation rate

Slower blood flow can lead to coagulation problems.

Question 19

What happens to blood flow when blood volume increases?

Answer 19

Blood flow tends to move at a slower velocity.

Slower blood flow can lead to coagulation problems and an increased risk of blood clots.

Question 20

What is the role of atrial natriuretic peptide (ANP)?

Answer 20

ANP is released from the right atrium when it becomes stretched, promoting sodium and water excretion.

ANP increases urine output and helps prevent volume overload.

Question 21

Where is brain natriuretic peptide (BNP) produced?

Answer 21

BNP is produced in the ventricles of the heart.

BNP is released when the ventricles are stretched and serves a similar function to ANP.

Question 22

What does an increase in BNP levels indicate?

Answer 22

An increase in BNP levels typically indicates worsening ventricular stretch and potential heart failure.

Monitoring BNP levels can help evaluate heart failure treatment progress.

Question 23

True or False: ANP and BNP have long-lasting effects on urine output.

Answer 23

False.

ANP and BNP effects are temporary, lasting about a week.

Question 24

What is oncotic pressure primarily determined by?

Answer 24

Oncotic pressure is primarily determined by plasma proteins, such as albumin.

Oncotic pressure helps retain fluid in the cardiovascular system.

Question 25

What happens to fluid distribution after significant blood loss?

Answer 25

Fluid redistributes between compartments to maintain blood volume. ## Footnote This includes movement from interstitial fluid to the cardiovascular system.

Question 26

Fill in the blank: Normal saline has no _____ in it.

Answer 26

colloids. ## Footnote This means that only a fraction of normal saline stays in the cardiovascular system after administration.

Question 27

What are synthetic colloids used for?

Answer 27

Synthetic colloids like dextran and hydroxyethyl starch are used to maintain oncotic pressure in the cardiovascular system. ## Footnote They provide volume expansion without using blood products.

Question 28

What is stretch relaxation in large veins?

Answer 28

Stretch relaxation is the response of smooth muscle in large veins to distention, causing the muscle to relax. ## Footnote This can lead to decreased blood pressure following rapid fluid administration.

Question 29

What is the effect of rapid intravenous fluid administration on blood pressure?

Answer 29

Blood pressure initially increases but often decreases shortly after due to fluid redistribution and stretch relaxation. ## Footnote This phenomenon is commonly observed after administering crystalloid fluids.

Question 30

What is the consequence of losing plasma proteins during blood loss?

Answer 30

Loss of plasma proteins reduces oncotic pressure, affecting the ability to retain fluid in the cardiovascular system. ## Footnote This can lead to further complications in maintaining blood volume.

Question 31

What happens if excessive normal saline is given during hemorrhage?

Answer 31

Excessive normal saline can lead to pulmonary edema. ## Footnote This occurs when too much fluid enters the interstitial space of the lungs.

Question 32

What is stretch relaxation in large veins?

Answer 32

A response of smooth muscle in large veins that relaxes when the veins become distended, reducing venous pressure over a period of minutes. ## Footnote Stretch relaxation helps accommodate increased blood volume without immediate pressure spikes.

Question 33

What is reverse stretch relaxation?

Answer 33

A response where the sympathetic nervous system overrides the natural relaxation of smooth muscle in veins, causing them to tighten in response to hemorrhage. ## Footnote This is part of the body's compensatory mechanisms during severe blood loss.

Question 34

What triggers the CNS ischemic response?

Answer 34

It occurs when there is low perfusion of the brain or brain stem for a few minutes, usually during severe hypotension. ## Footnote This response involves maximal sympathetic nervous system engagement to restore blood pressure.

Question 35

What happens to tissues during shock?

Answer 35

They experience dysfunction due to inadequate perfusion, leading to cell necrosis and release of intracellular contents that can worsen the condition. ## Footnote Common complications include hyperkalemia and acidosis.

Question 36

Which organ is particularly sensitive to underperfusion during shock?

Answer 36

The liver is one of the first organs to deteriorate under conditions of low perfusion. ## Footnote Renal failure typically takes longer to develop compared to liver dysfunction.

Question 37

How is cardiac output estimated using oxygen consumption?

Answer 37

By calculating the amount of oxygen delivered and unloaded in the systemic circulation based on arterial and venous oxygen content. ## Footnote The thick equation can be used to relate oxygen consumption to cardiac output.

Question 38

What is the normal oxygen consumption for an average healthy adult?

Answer 38

250 mL of O2 per minute. ## Footnote This value may vary based on individual characteristics like size and fitness level.

Question 39

How do you calculate the required cardiac output to meet oxygen demands?

Answer 39

Divide total oxygen consumption by the amount of oxygen delivered per deciliter of blood. ## Footnote For example, if 5 mL O2 is delivered per deciliter and consumption is 250 mL, the required output is 50 deciliters.

Question 40

What is cardiac reserve?

Answer 40

The maximum amount of cardiac output that can be achieved above baseline levels. ## Footnote A healthy adult may have a cardiac output upper limit around 25 liters per minute.

Question 41

What factors can reduce cardiac reserve?

Answer 41

* Age * Sedentary lifestyle * Heart diseases (e.g., valvular disease) * Coronary artery disease ## Footnote Cardiac reserve typically decreases with age and health status.

Question 42

What is the role of digoxin in heart failure?

Answer 42

It is a sodium-potassium ATPase pump inhibitor used as a last-resort treatment to improve heart function. ## Footnote While it can help, digoxin affects multiple systems and can have serious side effects.

Question 43

What happens when the heart fails to sustain adequate cardiac output?

Answer 43

The patient may require temporary support to survive while the heart recovers. ## Footnote This could involve pharmacological interventions or mechanical support.

Question 44

What are the components of the thick equation used for cardiac output?

Answer 44

It relates arterial oxygen content, venous oxygen content, and oxygen consumption to determine cardiac output. ## Footnote The equation helps in calculating how much blood must circulate to meet the body's oxygen needs.

Question 45

What is the significance of calcium and cholesterol deposits in valve diseases?

Answer 45

They lead to inflammation and structural changes in heart valves, contributing to dysfunction. ## Footnote These deposits can affect the normal functioning of the heart valves.

Question 46

What is cardiac reserve?

Answer 46

The ability of the heart to increase its output during increased activity or stress. ## Footnote Cardiac reserve can decrease with age and health conditions.

Question 47

What typically initiates valve diseases?

Answer 47

Inflammation leading to calcium and cholesterol deposits. ## Footnote This process can eventually lead to stenosis or regurgitation.

Question 48

What does a healthy valve look like?

Answer 48

Clean with a clear opening for coronary arteries. ## Footnote Healthy cusps fit tightly together.

Question 49

What is aortic stenosis?

Answer 49

A condition where the aortic valve becomes narrowed, making it difficult for blood to flow out of the heart. ## Footnote It is characterized by calcified buildup on the valve.

Question 50

How does calcified buildup affect valve function?

Answer 50

It makes it difficult for the valve to open and can lead to stenosis. ## Footnote The more calcification, the more stenotic the valve becomes.

Question 51

What happens when the valve does not close completely?

Answer 51

Blood is funneled back into the ventricle instead of into the coronary arteries. ## Footnote This condition is known as regurgitation.

Question 52

What is the most common heart valve problem?

Answer 52

Aortic stenosis. ## Footnote It affects approximately 1-2% of the population.

Question 53

What is a congenital bicuspid valve?

Answer 53

A valve with only two cusps instead of the normal three. ## Footnote This abnormality can lead to complications later in life.

Question 54

What is a common misconception about congenital bicuspid valves?

Answer 54

That everyone with this condition must have their valve replaced. ## Footnote Some individuals may not need replacement, especially if they are asymptomatic.

Question 55

What can happen if a congenital bicuspid valve develops complications?

Answer 55

It may lead to aortic stenosis or even an aortic aneurysm. ## Footnote Notable cases like Bono from U2 illustrate serious outcomes.

Question 56

What is the relationship between aortic stenosis and coronary arterial perfusion?

Answer 56

Aortic stenosis can impair coronary arterial perfusion due to obstruction. ## Footnote The heart has to work harder, exacerbating the issue.

Question 57

True or False: All patients with congenital bicuspid valves require surgery.

Answer 57

False. ## Footnote Many individuals may remain asymptomatic and not need surgery.