Where is the impulse from the SA node delayed, enabling atrial contraction to complete before the ventricles are stimulated and contract?
- A. AV node
- B. Bundle of His
- C. SA node
- D. Aorta
Correct Answer: A
Rationale: The impulse from the SA node is delayed at the AV node to allow time for the atria to contract before the ventricles. The AV node acts as a gatekeeper, slowing down the electrical signal before transmitting it to the Bundle of His, which then conducts the signal to the ventricles. This delay ensures proper coordination between atrial and ventricular contractions. Choices C and D are incorrect as the SA node does not delay its own impulse, and the aorta is not involved in the conduction system.
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The nurse is teaching a client about side effects of ACE inhibitors. What is the most important side effect to monitor?
- A. Cough
- B. Hyperkalemia
- C. Hypotension
- D. Dizziness
Correct Answer: A
Rationale: The correct answer is A: Cough. ACE inhibitors can cause a persistent, dry cough due to bradykinin accumulation. It is important to monitor for this as it can indicate potential angioedema, a serious adverse effect. Hyperkalemia (B) is a potential side effect but may not be as immediate or common as cough. Hypotension (C) is a common side effect but not as crucial to monitor as cough. Dizziness (D) is a common side effect but not as significant as cough in terms of potential complications.
What is the term that describes the inability of cardiac cells to respond to a new stimulus while they are still in contraction from a previous stimulus?
- A. Refractoriness
- B. Excitability
- C. Contractility
- D. Automaticity
Correct Answer: A
Rationale: The correct answer is A: Refractoriness. Refractoriness refers to the period during which cardiac cells are unable to respond to a new stimulus while still contracting from a previous stimulus. This is essential for preventing premature re-stimulation and ensuring proper cardiac function.
B: Excitability refers to the ability of cardiac cells to respond to a stimulus, which is the opposite of what is described in the question.
C: Contractility is the ability of cardiac cells to contract in response to an electrical stimulus, not related to the inability to respond to a new stimulus during contraction.
D: Automaticity is the ability of cardiac cells to spontaneously generate electrical impulses, unrelated to the inability to respond to a new stimulus during contraction.
What is a condition where the heart muscle is weakened and unable to pump blood effectively, often leading to heart failure?
- A. Cardiomyopathy
- B. Myocarditis
- C. Endocarditis
- D. Pericarditis
Correct Answer: A
Rationale: The correct answer is A: Cardiomyopathy. Cardiomyopathy refers to a condition where the heart muscle is weakened and unable to pump blood effectively, leading to heart failure. This is because the heart muscle becomes enlarged, thickened, or stiff, affecting its ability to pump blood efficiently.
Incorrect choices:
B: Myocarditis - Myocarditis is inflammation of the heart muscle, not necessarily associated with weakening of the heart muscle leading to heart failure.
C: Endocarditis - Endocarditis is inflammation of the inner lining of the heart chambers and valves, not directly related to the weakening of the heart muscle.
D: Pericarditis - Pericarditis is inflammation of the pericardium (the outer lining of the heart), and does not directly involve the weakening of the heart muscle.
What is the condition where the pericardium, the sac surrounding the heart, becomes inflamed, leading to chest pain and other symptoms?
- A. Pericarditis
- B. Myocarditis
- C. Endocarditis
- D. Pulmonary hypertension
Correct Answer: A
Rationale: Rationale:
1. Pericarditis is the inflammation of the pericardium, causing chest pain.
2. Myocarditis is inflammation of the heart muscle, not the pericardium.
3. Endocarditis is inflammation of the inner lining of the heart chambers.
4. Pulmonary hypertension is high blood pressure in the lungs, unrelated to pericardial inflammation.
In conclusion, pericarditis is the correct answer as it specifically refers to the inflammation of the pericardium, leading to chest pain.
The client on spironolactone (Aldactone) should avoid which type of food?
- A. Foods high in potassium
- B. Foods high in sodium
- C. Foods high in calcium
- D. Foods high in chloride
Correct Answer: A
Rationale: The correct answer is A: Foods high in potassium. Spironolactone is a potassium-sparing diuretic, meaning it helps the body retain potassium. Consuming foods high in potassium while on spironolactone can lead to hyperkalemia, which is an elevated level of potassium in the blood. This can result in serious health complications such as irregular heartbeats and muscle weakness. Therefore, it is crucial for clients on spironolactone to avoid foods high in potassium to prevent these adverse effects. Choices B, C, and D are incorrect because spironolactone does not specifically interact with sodium, calcium, or chloride in a way that necessitates avoiding foods high in these electrolytes.