Cardiovascular

Question 1

Blood pressure is the result of …

Answer 1

Peripheral vascular resistance and cardiac output. Changes in either the patient’s peripheral vascular resistance or cardiac output can result in corresponding increase or decrease in blood pressure.

Cardiac output equals heart rate time is stroke volume

Question 2

cardiac output is the amount of…

Answer 2

Blood ejected from the left ventricle into the systemic circulation in one minute. Cardiac output is a combination of the stroke volume and heart rate. If the heart rate significantly increases the cardiac output will increase causing an increase in blood pressure.

Stroke volume is the amount of blood ejected from the left ventricle during each systolic contraction. stroke volume is the result of three individual factors.

Question 3

Stroke volume is the result of the three factors

Answer 3

1. Preload
2. After load
3. Contractility

Question 4

What is preload

Answer 4

Preloaded is the amount of venous blood return to the right side of the heart. Preload depicts Venus fluids status and is affected by cardiovascular effort and volume status.

Question 5

What is Afterload

Answer 5

The amount of pressure the left ventricle must overcome to eject blood into the systemic circulation. Mainly afterload is affected by vasoconstriction vasodilation and volume status.

Question 6

What causes of increase and decrease a pre-load

Answer 6

Causes of increase Preload (Increase SV)
1. hypervolemia
2. acute heart failure exacerbation
3. obstructive or cardiogenic shock
Causes of decrease Preload (Decrease SV)
1. hypovolemia
2. untreated hypothyroidism
3. vasodilator or eight agent such as nicardipine, nitroprusside, nitroglycerin and hydralazine
4. diuretics
5. electrolyte imbalance - sodium and calcium

Question 7

What causes an increase and decrease afterload?

Answer 7

Causes of increased afterload
1. increased vascular resistance
2. Semilunar valvular stenosis
Causes of decreased afterload
1. hypovolemia
2. untreated hypothyroidism
3. Vasodilatory agents-Nicardipine, nitroprusside, nitroglycerin, hydralzine
4. diuretics
5. Electrolyte imbalance- sodium and calcium

Question 8

What is contractility

Answer 8

The forcefulness of each ventricular contraction during systole. This reflect starlings law. The more a ventricle has to expand to accomidate fluid the more forcefully it will have to contract to systematically circulate the blood

Question 9

Causes of increased and decreased contractility

Answer 9

Causes of increase contractility-increases SV
1. sympathetic stimulation
2. hypercalcemia
3. hyperthyroidism
4. positive inotropic agents such as digoxin, Epinephrine , or norepinephrine ( Levophed)

Causes a decrease contractility- decreases SV
1. parasympathetic stimulation
2. hypothyroidism
3. hyperkalemia
4. negative inotropic agents such as certain antiarrhythmics, calcium channel blocker’s, and beta blockers