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: Pleural effusion is the correct answer as it refers to the accumulation of excess fluid between the layers of the pleura surrounding the lungs and chest cavity. This condition can be caused by various factors such as infections, heart failure, or cancer. Pulmonary edema (choice B) involves fluid accumulation in the lungs' air sacs and is not specific to the pleura. Atelectasis (choice C) is the collapse or closure of a lung leading to airless lung tissue and is not related to fluid buildup. Sarcoidosis (choice D) is a condition characterized by the growth of tiny collections of inflammatory cells in different parts of the body, not specifically involving fluid accumulation in the pleural space.

Correct Answer: A

Rationale: The correct answer is A, Coronary artery bypass graft (CABG). This surgical procedure involves grafting a blood vessel to bypass a blocked coronary artery, improving blood flow to the heart muscle. Choice B, Valve replacement, is a procedure to replace a damaged heart valve and is not directly related to bypassing blocked arteries. Choice C, Stent placement, involves inserting a mesh tube to keep blocked arteries open and is different from grafting a blood vessel. Choice D, Angioplasty, is a procedure to widen narrowed or blocked arteries, typically using a balloon catheter, and does not involve grafting a blood vessel.

Correct Answer: A

Rationale: The correct answer is to hold the digoxin and notify the healthcare provider. A potassium level of 2.8 mEq/L indicates hypokalemia, which can increase the risk of digoxin toxicity. Holding the medication and informing the healthcare provider is crucial to prevent adverse effects. Choice B is incorrect because increasing the dose of digoxin would further raise the risk of toxicity. Choice C is incorrect as continuing the current dose could exacerbate the toxicity risk. Choice D is incorrect because administering potassium supplements alone is not sufficient to address the potential digoxin toxicity; the first step should be to hold the digoxin and seek 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.