Correct Answer: A

Rationale: The correct answer is A: 46.8; meets criteria for ARDS. The PaO /FiO ratio is calculated by dividing the arterial oxygen partial pressure (PaO) by the fraction of inspired oxygen (FiO). In this case, PaO is 78 mm Hg and FiO is 0.6 (60%). Therefore, the calculation would be 78/0.6 = 130. This value is less than 300, which is indicative of ARDS according to the Berlin criteria. Choices B and C are incorrect as they do not align with the criteria for ARDS. Choice D is incorrect because the data provided is sufficient to compute the ratio.

Correct Answer: D

Rationale: The correct answer is D because a patient with a history of fluid overload due to heart failure is at the greatest risk of developing acute kidney injury. Heart failure can lead to decreased kidney perfusion causing acute kidney injury. In this scenario, the patient's fluid overload exacerbates the situation, further compromising kidney function. Choice A is incorrect as aminoglycosides can cause kidney injury but the duration of 6 days is less concerning compared to chronic fluid overload from heart failure in choice D. Choice B is incorrect because controlled hypertension does not directly increase the risk of acute kidney injury. Choice C is incorrect as the patient being discharged 2 weeks earlier after aminoglycoside therapy does not necessarily indicate a higher risk compared to chronic fluid overload.

Correct Answer: B

Rationale: The correct answer is B: Dimming lights during the night. This intervention helps reduce stress by creating a more calming environment, promoting rest and sleep. Constant observation (choice A) may increase stress due to lack of privacy. Frequent group rounds (choice C) may disrupt rest. Use of tile floors (choice D) is unrelated to addressing noise and light stress.

Correct Answer: D

Rationale: The correct answer is D: Work of breathing. Work of breathing refers to the amount of effort required to maintain a specific level of ventilation. This includes the energy needed for inhalation and exhalation. Compliance (A) refers to the ease with which the lungs expand, resistance (B) is the opposition to airflow in the airways, and tidal volume (C) is the amount of air moved in and out of the lungs during normal breathing. Work of breathing encompasses the overall energy expenditure involved in the breathing process, making it the most appropriate term in this context.

Correct Answer: C

Rationale: The correct answer is C: Rhinorrhoea or otorrhoea with Halo sign. This finding is consistent with a basilar skull fracture because it indicates a cerebrospinal fluid (CSF) leak from the skull base. The Halo sign refers to a ring of CSF surrounded by blood, which can be seen on a white absorbent pad. This specific sign is a classic indicator of a basilar skull fracture, as the CSF leakage from the ears or nose can be tinged with blood due to the fracture disrupting nearby blood vessels. For the other choices: A: Hematemesis and abdominal distention are not typical manifestations of a basilar skull fracture. They are more indicative of gastrointestinal issues or internal bleeding. B: Asymmetry of the face and eye movements can be seen with facial nerve or orbital injuries, but it is not specific to a basilar skull fracture. D: Abnormal position and movement of the arm are not directly related to a