Correct Answer: A

Rationale: The correct answer is A. A decrease in the arterial pressure (hypotension) with a low diastolic pressure (46 mmHg) may indicate inadequate perfusion, possibly due to inadequate cardiac output from the mechanical ventilation. This suggests that a change in ventilator settings may be required to improve oxygenation and perfusion. Option B is incorrect because a heart rate of 58 beats/minute alone does not provide direct information on the patient's hemodynamic status. Option C is incorrect as an increased stroke volume would usually be a positive indicator; it does not necessarily indicate a need for changing the ventilator settings. Option D is incorrect as a stroke volume variation of 12% is within normal limits and does not necessarily require a change in ventilator settings.

Correct Answer: C

Rationale: The correct answer is C: Begin phenylephrine (Neo-Synephrine) for systolic BP < 90 mm Hg. The nurse should implement this order first because the patient's low blood pressure (75/50 mm Hg) indicates hypotension, which can lead to inadequate perfusion to vital organs. Phenylephrine is a vasoconstrictor that can help increase the patient's blood pressure and improve perfusion. It is crucial to address hypotension promptly to prevent further complications. Choice A is incorrect because maintaining the patient's temperature above 96.8°F is not the most urgent concern in this scenario. Choice B is incorrect as obtaining a basic metabolic panel every 4 hours is not the immediate priority when the patient is experiencing hypotension. Choice D is incorrect as drawing arterial blood gas every 4 hours is not the most urgent intervention needed to address the patient's low blood pressure.

Correct Answer: A

Rationale: The correct answer is A: Apply wet sheets and a fan to the patient. This is the initial treatment for hyperthermia to aid in lowering the body temperature. Wet sheets help in evaporative cooling, while a fan enhances heat loss through convection. This approach is crucial in managing heat-related illnesses quickly. Choices B, C, and D are incorrect as they do not directly address the urgent need to reduce the patient's elevated core temperature. Providing O2, IV fluids, or acetaminophen can be considered later in the management, but the priority is to rapidly lower the body temperature in a hyperthermic patient to prevent further complications.

Correct Answer: A

Rationale: The correct answer is A: Assess the patient’s pain using a standardized pain scale. The first step is to assess the severity and nature of the pain to determine the appropriate intervention. This allows the nurse to understand the pain intensity and characteristics, which guides the choice of analgesic and dosing. Administering analgesics (B) without proper assessment can lead to inappropriate treatment. Notifying the healthcare provider (C) is important but assessing the pain should come first. Repositioning the patient (D) may provide comfort but addressing the pain directly is the priority.

Correct Answer: A

Rationale: The correct answer is A: Increase functional residual capacity. Positive end-expiratory pressure (PEEP) helps increase the functional residual capacity by keeping the alveoli open at the end of expiration. This prevents alveolar collapse, improves ventilation-perfusion matching, and enhances oxygenation. B: Prevent collapse of unstable alveoli - This is incorrect because PEEP actually helps prevent the collapse of all alveoli, not just unstable ones. C: Improve arterial oxygenation - This is partially correct, but the primary mechanism through which PEEP improves oxygenation is by increasing functional residual capacity. D: Open collapsed alveoli - This is incorrect because PEEP helps prevent alveolar collapse rather than actively opening already collapsed alveoli.