Which of the following classes of medications protects the ischemic myocardium by blocking catecholamines and sympathetic nerve stimulation?
-
Solution
Beta-adrenergic blockers
Option A: Beta-adrenergic blockers work by blocking beta receptors in the myocardium, reducing the response to catecholamines and sympathetic nerve stimulation. They protect the myocardium, helping to reduce the risk of another infarction by decreasing the workload of the heart and decreasing myocardial oxygen demand.
Option B: Calcium channel blockers reduce the workload of the heart by decreasing the heart rate.
Option C: Narcotics reduce myocardial oxygen demand, promote vasodilation, and decreased anxiety.
Option D: Nitrates reduce myocardial oxygen consumption by decreasing left ventricular end-diastolic pressure (preload) and systemic vascular resistance (afterload).
What is the most appropriate nursing response to a myocardial infarction client who is fearful of dying?
-
Solution
“Tell me about your feeling right now.”
Option A: Validation of the client’s feelings is the most appropriate response. It gives the client a feeling of comfort and safety.
Options B, C, and D: The other three responses give the client false hope. No one can determine if a client experiencing MI will feel or get better and therefore, these responses are inappropriate.
What is the first intervention for a client experiencing myocardial infarction?
-
Solution
Administer oxygen
Option B: Administering supplemental oxygen to the client is the first priority of care. The myocardium is deprived of oxygen during an infarction, so additional oxygen is administered to assist in oxygenation and prevent further damage.
Options A and C: Morphine and sublingual nitroglycerin are also used to treat MI, but they’re more commonly administered after the oxygen.
Option D: An ECG is the most common diagnostic tool used to evaluate MI.
Which of the following diagnostic tools is most commonly used to determine the location of myocardial damage?
-
Solution
Electrocardiogram
Option D: The ECG is the quickest, most accurate, and most widely used tool to determine the location of myocardial infarction.
Option B: Cardiac enzymes are used to diagnose MI but can’t determine the location.
Option C: An echocardiogram is used most widely to view myocardial wall function after an MI has been diagnosed.
Option A: Cardiac catheterization is an invasive study for determining coronary artery disease and may also indicate the location of myocardial damage, but the study may not be performed immediately.
After an anterior wall myocardial infarction, which of the following problems is indicated by auscultation of crackles in the lungs?
-
Solution
Left-sided heart failure
Option A: The left ventricle is responsible for the most of the cardiac output. An anterior wall MI may result in a decrease in left ventricular function. When the left ventricle doesn’t function properly, resulting in left-sided heart failure, fluid accumulates in the interstitial and alveolar spaces in the lungs and causes crackles.
Options B, C, and D: Pulmonic and tricuspid valve malfunction cause right-sided heart failure.
Which of the following complications is indicated by a third heart sound (S3)?
-
Solution
Ventricular dilation
Option A: Rapid filling of the ventricles causes vasodilation that is auscultated as S3.
Option B and D: Increased atrial contraction or systemic hypertension can result is a fourth heart sound.
Option C: Aortic valve malfunction is heard as a murmur.
After myocardial infarction, serum glucose levels and free fatty acids are both increased. What type of physiologic changes are these?
-
Solution
Metabolic
Option D: Both glucose and fatty acids are metabolites whose levels increase after a myocardial infarction.
Options A and C: Mechanical changes are those that affect the pumping action of the heart, and electrophysiologic changes affect conduction.
Option B: Hematologic changes would affect the blood.
What supplemental medication is most frequently ordered in conjuction with furosemide (Lasix)?
-
Solution
Potassium
Option C: Supplemental potassium is given with furosemide because of the potassium loss that occurs as a result of this diuretic.
Options A and D: Chloride and sodium aren’t lost during diuresis.
Option B: Digoxin acts to increase contractility but isn’t given routinely with furosemide.
Which of the following conditions is most commonly responsible for myocardial infarction?
-
Solution
Coronary artery thrombosis
Option C: Coronary artery thrombosis causes occlusion of the artery, leading to myocardial death.
Option A: An aneurysm is an outpouching of a vessel and doesn’t cause an MI.
Option D: Renal failure can be associated with MI but isn’t a direct cause.
Option B: Heart failure is usually the result of an MI.
What is the primary reason for administering morphine to a client with myocardial infarction?
-
Solution
To decrease oxygen demand on the client’s heart
Option D: Morphine is administered because it decreases myocardial oxygen demand.
Options A, B, and C: Morphine will also decrease pain and anxiety while causing sedation, but isn’t primarily given for those reasons.