Correct Answer: A

Rationale: The correct answer is to monitor INR for a patient on warfarin therapy. INR monitoring is crucial as it helps assess the therapeutic effectiveness and safety of warfarin. INR stands for International Normalized Ratio, and it measures the blood's ability to clot. Monitoring potassium levels (Choice B) is not specific to warfarin therapy. Monitoring platelet count (Choice C) is important but not the primary lab value for assessing warfarin therapy. Monitoring sodium levels (Choice D) is not directly related to warfarin therapy.

Correct Answer: A

Rationale: The correct answer is A: Hypokalemia. Furosemide, a loop diuretic, commonly causes the loss of potassium in the urine, leading to hypokalemia. This electrolyte imbalance can result in various complications such as cardiac arrhythmias and muscle weakness. Choice B, Hyponatremia, is not typically associated with furosemide use. Choice C, Hyperkalemia, is the opposite of the expected electrolyte imbalance caused by furosemide. Choice D, Hypercalcemia, is not a common side effect of furosemide.

Correct Answer: D

Rationale: The correct answer is D: 'Trim toenails straight across.' In clients with diabetes, trimming toenails straight across is important to prevent ingrown toenails, reducing the risk of infections. Soaking feet in warm water daily (choice A) can lead to dry skin and potentially cause skin breakdown in diabetic clients. While wearing cotton socks (choice B) is beneficial for good foot hygiene, it is not as crucial as trimming toenails correctly. Applying lotion to feet after bathing (choice C) is helpful for moisturizing the skin, but the emphasis should be on nail care to prevent complications like ingrown toenails.

Correct Answer: B

Rationale: Oliguria is a sign of decreased cardiac output. Decreased cardiac output can lead to poor renal perfusion, resulting in decreased urine output (oliguria). This requires immediate intervention to improve cardiac function and perfusion. Shivering (Choice A) is a response to cold stress and does not directly indicate decreased cardiac output. Bradypnea (Choice C) refers to abnormally slow breathing rate and is more indicative of respiratory issues rather than decreased cardiac output. Constricted pupils (Choice D) are associated with the parasympathetic nervous system response and not directly related to cardiac output.

Correct Answer: C

Rationale: The correct answer is C. A serum creatinine level of 2.8 mg/dL indicates impaired kidney function and should be reported to the healthcare provider. Elevated serum creatinine levels are indicative of decreased kidney function and potential progression of chronic kidney disease. Choices A, B, and D are within normal ranges and do not signify immediate concerns related to kidney disease. Urine output of 80 mL/hr is appropriate, a blood pressure of 140/90 mm Hg is considered prehypertensive but not acutely concerning, and a heart rate of 72/min falls within the normal range.