Inotropes, Vasopressors, and Vasodilators

Question 1

What condition is indicated by SBP < 90 mm Hg, CI < 2.2 L/min/m2, and PCWP > 12 mm Hg?

Answer 1

Cardiogenic shock

Cardiogenic shock is a state of inadequate blood flow to the body’s organs due to the heart’s inability to pump effectively.

Question 2

According to the SOAP II trial, which medication showed decreased rates of death in patients with cardiogenic shock?

Answer 2

Norepinephrine

Patients randomized to receive norepinephrine had lower mortality compared to those receiving dopamine (p = 0.03).

Question 3

What is the mechanism of action of milrinone?

Answer 3

Phosphodiesterase inhibitor that increases cAMP

Milrinone causes an increase in myocardial contractility and has a dose-dependent vasodilatory effect.

Question 4

In patients with LV systolic dysfunction, which agent is most appropriate when exhibiting signs of shock?

Answer 4

Dopamine

Dopamine is preferred due to its inotropic and vasoconstrictive properties.

Question 5

What is no reflow in the context of percutaneous interventions?

Answer 5

Failure of oxygen reperfusion to ischemic tissue

This condition can lead to cell injury, edema, and platelet plugs due to reactive oxygen species.

Question 6

Which agents are used to treat vasospasm?

Answer 6

• Diltiazem
• Verapamil
• Sodium nitroprusside
• Nitroglycerin

These are preferred over acetylcholine, which is ineffective in patients with endothelial dysfunction.

Question 7

What is the preferred vasodilator for acute vasodilatory challenges in pulmonary arterial hypertension?

Answer 7

Inhaled nitric oxide (NO)

It has a rapid onset and minimal systemic effects.

Question 8

What is the usual starting dose range for norepinephrine?

Answer 8

2 mcg/min to 30 mcg/min

Norepinephrine is commonly used in septic shock and cardiogenic shock.

Question 9

What is the treatment for severe anaphylactoid reactions secondary to contrast media?

Answer 9

Epinephrine in bolus doses of 10 mcg

Administer until MAP is >60 mm Hg; IV steroids should not be used alone in severe reactions.

Question 10

True or False: Phenylephrine increases heart rate.

Answer 10

False

Phenylephrine is a pure alpha agonist with minimal beta-adrenergic effects.

Question 11

What should be questioned before administering nitroglycerin to a patient with pulmonary arterial hypertension?

Answer 11

Use of phosphodiesterase inhibitors

These can interact with nitrates, leading to hypotension.

Question 12

What is the initial treatment for hypotension associated with inferior wall and right ventricular infarction?

Answer 12

Generous IV volume administration

This is crucial before considering medications like nitroglycerin.

Question 13

What does nitric oxide do to vascular smooth muscle?

Answer 13

Increases cGMP production, leading to relaxation

It also inhibits platelet aggregation and neutrophil adhesion.

Question 14

What is the effect of labetalol in hypertensive crises?

Answer 14

Preferred treatment due to vasodilatory properties

It is particularly useful in patients with cardiac ischemia.

Question 15

What is a major risk associated with sodium nitroprusside?

Answer 15

Cyanide toxicity

It is released during metabolism and can cause serious complications.

Question 16

What is the role of methylergonovine in vascular health?

Answer 16

Acts as a serotonin receptor agonist

It can cause vasodilation in healthy endothelium but may lead to vasoconstriction in abnormal conditions.

Question 17

How does dopamine’s effect vary with dosage?

Answer 17

Low doses affect dopamine receptors; higher doses stimulate alpha-1 receptors

This results in increased BP at higher doses.

Question 18

What is the effect of low-dose dopamine (<5 mcg/kg/min)?

Answer 18

Primarily vasodilation via dopamine receptors

It was previously thought to protect renal function, but this is not supported by current data.

Question 19

What is the renal protective effect of dopamine?

Answer 19

Dopamine may help resolve oliguria but does not improve other renal outcomes

Data do not support its prophylactic use in preventing kidney injury during catheterization procedures.

Question 20

What factors affect tissue ischemia and sloughing during drug infiltration?

Answer 20

Alpha-1 vasoconstriction properties and local drug concentration

The rate of infusion does not affect tissue ischemia.

Question 21

What should be done once extravasation is observed?

Answer 21

Infusion should be discontinued and slow aspiration of the drug should be performed

Cold or warm compresses may help with other medications, but catecholamines require immediate treatment with phentolamine.

Question 22

What is phentolamine used for?

Answer 22

To block hypertensive effects of catecholamines and diagnose pheochromocytoma

Phentolamine is prepared by diluting 5 mg in 10 mL of normal saline and injecting subcutaneously.

Question 23

Which inotropic agent is indicated for low cardiac output?

Answer 23

Dobutamine

It does not significantly impact afterload.

Question 24

What is the effect of dopamine at low doses?

Answer 24

Strong beta agonist but can increase systemic vascular resistance (SVR)

This is not ideal for patients who are not in shock.

Question 25

What is the primary action of nitroglycerin at low doses (<30 mcg/min)?

Answer 25

Venodilation

At doses above 30 mcg/min, it exhibits balanced venous and arterial dilation.

Question 26

What effect does nitroglycerin have on coronary collateral flow compared to nitroprusside?

Answer 26

Increases coronary collateral flow

Nitroprusside decreases coronary collateral flow.

Question 27

What should be prioritized for a patient not exhibiting adverse reactions to nitroglycerin?

Answer 27

Uptitration of nitroglycerin

Morphine should only be used for pain unrelieved by nitroglycerin.

Question 28

True or False: Early IV metoprolol has been shown to reduce infarct size in patients experiencing STEMI.

Answer 28

False

Studies indicate it has not shown a reduction in infarct size.

Question 29

What are antidotes for drug extravasations other than catecholamines?

Answer 29

Hyaluronidase and sodium thiosulfate

These compounds are used for other drug extravasations.