Correct Answer: B

Rationale: Serum troponin is the most specific and sensitive indicator of myocardial infarction. Troponin levels rise within 3-4 hours after myocardial damage, peak at 10-24 hours, and remain elevated for up to 10-14 days. Creatine kinase (CK) and myoglobin can also be elevated in myocardial infarction, but troponin is more specific to cardiac muscle damage. C-reactive protein (CRP) is a marker of inflammation and is not specific for myocardial infarction.

Correct Answer: B

Rationale: A serum potassium level of 5.5 mEq/L is concerning in a client with ESRD scheduled for hemodialysis as it indicates hyperkalemia, which can lead to serious cardiac complications. Hyperkalemia can be exacerbated during hemodialysis, making it crucial to closely monitor serum potassium levels before the procedure. Monitoring serum creatinine, serum calcium, or hemoglobin levels is important in managing ESRD but is not the immediate focus before hemodialysis. Therefore, option B is the correct choice.

Correct Answer: B

Rationale: The correct answer is B. Moisturizing between the toes can create a moist environment that fosters fungal infections. Checking the feet daily for cuts or blisters (choice A) is correct in diabetes management to prevent complications. Wearing comfortable shoes that fit well (choice C) and avoiding walking barefoot (choice D) are also essential in preventing foot ulcers and injuries in diabetic patients.

Correct Answer: B

Rationale: Evaluating daily renal laboratory studies is crucial in this scenario. The client has impaired renal function, recent GI bleeding, and is at risk for further kidney damage due to ibuprofen use. Monitoring renal labs helps assess kidney function and detect any progressive elevations, guiding further interventions. Option A is not directly related to renal function monitoring. Option C focuses more on urine appearance than renal function assessment. Option D mentions polyuria, which is excessive urine output, but the question describes a client with reduced renal output.

Correct Answer: C

Rationale: The correct answer is C. A tidal volume of 300 ml is concerning in a client with ARDS on mechanical ventilation because it indicates hypoventilation, which can lead to inadequate gas exchange and worsening respiratory status. This finding requires immediate intervention to optimize ventilation and oxygenation. Options A, B, and D are not as critical in this scenario. An oxygen saturation of 90% may be acceptable depending on the client's baseline condition and the target range set by the healthcare provider. A respiratory rate of 28 breaths per minute is slightly elevated but may not be immediately alarming. A blood pressure of 110/70 mmHg is within normal limits and does not require urgent intervention.