Correct Answer: D

Rationale: The correct answer is D because it shows empathy and promotes patient education. By describing the procedure and its necessity, the nurse can alleviate the patient's anxiety and build trust. This approach allows the patient to feel informed and in control, reducing fear and increasing cooperation. It also demonstrates respect for the patient's feelings and promotes a therapeutic relationship. Choice A is incorrect as it disregards the patient's fear and can lead to increased distress. Choice B might be an option, but it doesn't address the patient's anxiety in the moment. Choice C, while helpful in some cases, doesn't directly address the patient's specific fear of the blood draw procedure.

Correct Answer: A

Rationale: The correct answer is A: Graduated compression stockings. These stockings help prevent blood from pooling in the legs, reducing the risk of DVT and PE. They improve circulation and reduce venous stasis. Option B, heparin, is used for treatment, not prevention. Option C, sequential compression devices, help prevent DVT but are not as effective as compression stockings. Option D, strict bed rest, can actually increase the risk of DVT by reducing blood flow.

Correct Answer: A

Rationale: The correct answer is A: New ST segment elevation is noted on the cardiac monitor. This finding is concerning because it may indicate myocardial ischemia or infarction, which can be exacerbated by the physiological stress of weaning from mechanical ventilation. It is crucial to address any cardiac issues before initiating a spontaneous breathing trial to prevent potential cardiac complications during the weaning process. Explanation for why the other choices are incorrect: B: Enteral feedings being given through an orogastric tube are not contraindicated for starting a spontaneous breathing trial. C: Scattered rhonchi heard when auscultating breath sounds may indicate retained secretions but are not a contraindication for a spontaneous breathing trial. D: The use of HYDROmorphone to treat postoperative pain is not a contraindication for a spontaneous breathing trial unless it is causing respiratory depression, which would need to be addressed separately.

Correct Answer: C

Rationale: Correct Answer: C - Regular insulin Rationale: 1. Insulin promotes cellular uptake of potassium. 2. When insulin is administered, it moves potassium from extracellular to intracellular space. 3. This decreases plasma potassium levels safely. 4. Other options do not directly lower potassium levels in the same manner. Summary of Other Choices: A: Sodium polystyrene sulfonate - exchanges sodium for potassium in the intestines, not reducing total body potassium. B: Sodium polystyrene sulfonate with sorbitol - similar to A, does not reduce total body potassium. D: Calcium gluconate - does not directly lower potassium levels, used for treating hyperkalemia-induced cardiac toxicity.

Correct Answer: B

Rationale: The correct answer is B: Oxygen that is chemically combined with hemoglobin. This is because oxygen primarily travels in the blood by binding to hemoglobin in red blood cells, forming oxyhemoglobin. This process allows for efficient transport of oxygen to tissues throughout the body. Choices A, C, and D are incorrect because: A: Alveolar oxygen tension refers to the partial pressure of oxygen in the alveoli of the lungs, not the specific form of oxygen in the blood. C: Oxygen physically dissolved in plasma refers to the small amount of oxygen that is not bound to hemoglobin and is less significant in oxygen transport compared to oxygen bound to hemoglobin. D: Total oxygen consumption is the overall amount of oxygen utilized by the body, not specifically the form of oxygen bound to hemoglobin for transport.