Correct Answer: A

Rationale: The correct answer is, 'The Coumadin takes several days to work, so the IV heparin will be used until the Coumadin reaches a therapeutic level.' Warfarin (Coumadin) is an oral anticoagulant that takes time to reach its full effect, typically a few days. In the meantime, IV heparin is used to provide immediate anticoagulation until the Coumadin levels become therapeutic. Option B is incorrect because discontinuing the IV heparin abruptly without reaching a therapeutic level with Coumadin can increase the risk of clot formation. Option C is incorrect because heparin and Coumadin do not work together to dissolve clots; they both have anticoagulant effects but work differently. Option D is incorrect because IV heparin does not directly increase the effects of Coumadin; they have different mechanisms of action.

Correct Answer: A

Rationale: The correct answer is A. The client's statement indicates a need for further teaching because the flowmeter indicates the flow rate of oxygen, not the total amount of oxygen being delivered. Choices B, C, and D demonstrate understanding of safety measures and indications for seeking medical attention in relation to home oxygen therapy, making them appropriate statements.

Correct Answer: C

Rationale: The correct answer is that troponin is a heart muscle protein that appears in the bloodstream when there is damage to the heart. Troponin is a specific marker for heart muscle damage, particularly seen in conditions like myocardial infarction. Choice A is incorrect as troponin is not an enzyme that indicates damage to brain and skeletal muscle tissues. Choice B is incorrect as troponin is not a protein whose levels reflect the risk for coronary artery disease; it indicates heart muscle damage. Choice D is incorrect as troponin is not a protein that helps transport oxygen throughout the body; its presence in the bloodstream is specific to heart muscle damage.

Correct Answer: D

Rationale: The correct answer is to instruct the client to use pursed-lip breathing. This technique helps improve breathing efficiency by keeping the airways open during exhalation and reducing air trapping. Restricting fluid intake to less than 2 L/day is not appropriate for a client with COPD, as they need adequate hydration. Using the upper chest for respiration is incorrect as it promotes shallow breathing, which is not ideal for COPD patients. While exercise is beneficial, early-morning hours may not be the best time for clients with COPD due to increased respiratory distress in the morning.

Correct Answer: C

Rationale: When providing instructions for home oxygen therapy, it is important to ensure safety and proper care. Choices A, B, and D are all essential instructions for the client and family. Choice C, 'Apply petroleum jelly around and inside the nares,' is incorrect. Petroleum jelly should not be used near oxygen sources as it is flammable and can increase the risk of fire hazard. Therefore, this instruction should not be included in the teaching.