Correct Answer: C

Rationale: The correct answer is C: Insertion of a vena cava filter. This is a strategy for preventing thromboembolism in patients at risk who cannot take anticoagulants. The vena cava filter prevents blood clots from traveling to the lungs by trapping them in the inferior vena cava. It is a mechanical device that does not interfere with the body's clotting process. Explanation of why other choices are incorrect: A: Administration of two aspirin tablets every 4 hours is not an effective strategy for preventing thromboembolism in high-risk patients. Aspirin is an antiplatelet agent and may not be sufficient for preventing blood clots in these patients. B: Infusion of thrombolytics is used for breaking down blood clots that have already formed, not for prevention. It is not a suitable option for preventing thromboembolism in at-risk patients. D: Subcutaneous heparin administration every 12

Correct Answer: A

Rationale: The correct answer is A because in ARDS, there is a severe impairment in gas exchange leading to hypoxemia. Decreasing PaO2 levels despite increased FiO2 administration indicate poor oxygenation, a hallmark of ARDS. Elevated alveolar surfactant levels (Choice B) do not directly correlate with ARDS pathophysiology. Increased lung compliance with increased FiO2 administration (Choice C) is not characteristic of ARDS, as ARDS leads to decreased lung compliance. Respiratory acidosis associated with hyperventilation (Choice D) is not a typical finding in ARDS, as hyperventilation is usually present in an attempt to compensate for hypoxemia.

Correct Answer: A

Rationale: The correct answer is A because allowing family members to remain at the bedside can provide emotional support and comfort to the patient, helping them feel safe in the critical care setting. Family presence can also facilitate communication and understanding between the healthcare team and the patient. Choice B is incorrect because consulting with the charge nurse before making patient care decisions may not directly contribute to the patient feeling safe. Choice C is incorrect because providing informal conversation about work-related topics may not address the patient's need for safety and security in the critical care setting. Choice D is incorrect because explaining how to communicate for assistance is important for patient care but may not directly contribute to the patient's sense of safety in the critical care setting.

Correct Answer: D

Rationale: The correct answer is D: Adequate pain control. Pain can significantly disrupt sleep in critically ill patients. By ensuring adequate pain control, the nurse can help improve the patient's ability to rest and sleep. This intervention targets a key factor affecting sleep cycles in critically ill patients. Repositioning every 2 hours (A) may help prevent pressure ulcers but does not directly address sleep improvement. Hypnotic medications (B) may have adverse effects and are not recommended as a first-line intervention. Five-minute back effleurage (C) may provide temporary relaxation but is not as effective as adequate pain control in improving sleep quality.

Correct Answer: D

Rationale: The correct answer is D because using an end-tidal CO2 monitor is the most reliable method to confirm correct endotracheal tube placement in the trachea. This method detects exhaled CO2, indicating proper tube placement in the trachea. It is a quick and efficient way to confirm placement without delay, reducing the risk of complications. A: Auscultating for bilateral breath sounds is not as reliable because breath sounds may be heard even if the tube is misplaced. B: Obtaining a portable chest x-ray is not the best initial action as it takes time and delays confirming tube placement. C: Observing chest movement may not provide conclusive evidence of proper tube placement and can lead to misinterpretation. In summary, using an end-tidal CO2 monitor is the most accurate and efficient method to verify correct endotracheal tube placement compared to the other options.