Cardiovascular System Exam

Correct Answer: A

Rationale: The correct answer is A: Platelet count. When administering enoxaparin (Lovenox) for DVT prophylaxis, it is crucial to monitor the platelet count as enoxaparin can lead to thrombocytopenia, a decrease in platelet levels. Monitoring the platelet count helps in early detection of this potential adverse effect. Choices B, C, and D are incorrect because PT/INR, aPTT, and hemoglobin levels are not the most important lab values to monitor specifically for enoxaparin administration and DVT prophylaxis.

Correct Answer: A

Rationale: Automaticity is the correct answer because it refers to the inherent ability of cardiac cells to generate electrical impulses without the need for external stimulation. Contractility (Choice B) is the ability of the heart muscle to contract and generate force, not related to electrical impulse generation. Conductivity (Choice C) refers to the ability of cardiac cells to transmit electrical impulses from cell to cell, not the spontaneous generation of impulses. Refractoriness (Choice D) is the period during which the cardiac cells are recovering and not able to respond to a new stimulus, not the spontaneous generation of impulses.

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 and excrete sodium. Consuming foods high in potassium while on spironolactone can lead to an excess of potassium in the body, potentially causing hyperkalemia. Choices B, C, and D are incorrect because spironolactone does not directly interact with sodium, calcium, or chloride in a way that would require specific dietary restrictions related to these minerals.

Correct Answer: A

Rationale: In this scenario, the nurse's priority action should be to hold the digoxin and notify the healthcare provider. A heart rate of 48 bpm is low, and digoxin, being a medication that can further decrease the heart rate, should be withheld. Administering the digoxin as ordered (Choice B) would not be appropriate in this situation as it can exacerbate bradycardia. Atropine (Choice C) is not the initial treatment for this scenario; holding the digoxin is the first action. Increasing the dose of digoxin (Choice D) would be contraindicated due to the client's bradycardia. Therefore, the correct action is to hold the digoxin and inform the healthcare provider for further guidance.

Correct Answer: A

Rationale: The correct answer is A: Contractility. Contractility specifically refers to the change in the force of contraction of the heart muscle without changing its length. In this scenario, the focus is on the change in the inotropic state of the muscle, which directly relates to contractility. Choice B, Excitability, refers to the ability of a cell to respond to a stimulus, not specifically related to changes in contractile force. Choice C, Refractoriness, pertains to the period during which a cell is unresponsive to a new stimulus. Choice D, Automaticity, refers to the ability of cardiac cells to spontaneously generate electrical impulses.