The patient has elevated blood urea nitrogen (BUN) and serum creatinine levels with a normal BUN/creatinine ratio. These levels most likely indicate

Correct Answer: B

Rationale: The elevated BUN and serum creatinine levels with a normal BUN/creatinine ratio suggest a pre-renal cause, indicating decreased renal perfusion. This is consistent with acute kidney injury (AKI) such as acute tubular necrosis (ATN). In ATN, there is damage to the renal tubules leading to impaired filtration and elevated BUN and creatinine levels. Hypovolemia and fluid resuscitation would typically result in a high BUN/creatinine ratio due to altered reabsorption. Increased nitrogen intake would not lead to elevated creatinine levels. Therefore, choice B is correct as it aligns with the presentation of elevated BUN and creatinine levels with a normal ratio.

Correct Answer: A

Rationale: The correct answer is A: Sodium polystyrene sulfonate. It works by exchanging sodium ions for potassium ions in the intestine, reducing plasma potassium levels. Step 1: Administering sodium polystyrene sulfonate orally or rectally. Step 2: It binds with potassium in the gut, leading to fecal elimination. Step 3: This process helps lower both plasma potassium levels and total body potassium content safely. Choices B, C, and D are incorrect. B: Sodium polystyrene sulfonate with sorbitol can cause intestinal necrosis. C: Regular insulin temporarily shifts potassium into cells but doesn't reduce total body potassium. D: Calcium gluconate only stabilizes cardiac membrane potential without reducing potassium levels.

Correct Answer: C

Rationale: The correct answer is C because the statement "I will drink coffee and cola drinks throughout the day" indicates a lack of understanding regarding proper hydration. Coffee and cola drinks contain caffeine, which can lead to increased fluid loss and exacerbate dehydration. It is important to educate the patient that these beverages are not suitable for maintaining proper hydration levels. Choice A is not the best indicator for additional teaching as it shows the patient's intention to drink an adequate amount of fluids daily. Choice B, while not ideal, still acknowledges the importance of drinking water when thirsty. Choice D is also not the best indicator for additional teaching as it demonstrates the patient's awareness of avoiding alcohol-containing drinks, which can contribute to dehydration.

Correct Answer: C

Rationale: The correct answer is C because administering furosemide 40 mg IV push is the priority intervention for a patient with symptoms of fluid overload, such as weight gain, edema, and crackles. Furosemide is a potent diuretic that will help reduce fluid volume in the body, including the lungs, improving respiratory status. Weighing the patient, fluid restriction, and maintaining accurate intake and output records are important but secondary interventions compared to addressing the immediate issue of fluid overload. Options A and B do not provide a clear rationale for their choices, making them incorrect. Option D is incomplete.

Correct Answer: C

Rationale: Renal function does not represent a possible source of input for the internal body pool because it refers to the excretory system's function of filtering waste and excess substances from the blood, rather than introducing substances into the body. Inhalation introduces gases or particles into the body through the respiratory system. Intravenous injection delivers substances directly into the bloodstream. Absorption through the skin allows substances to enter the body through the skin barrier. Renal function involves filtering and eliminating substances from the body, making it the only choice that does not add to the internal body pool.