The most common cause of acute kidney injury in critically ill patients is

Correct Answer: A

Rationale: The correct answer is A: sepsis. Sepsis is a leading cause of acute kidney injury in critically ill patients due to the systemic inflammatory response leading to kidney damage. Fluid overload (B) can contribute but is not the primary cause. Medications (C) and hemodynamic instability (D) can also lead to acute kidney injury but are not as common as sepsis in critically ill patients.

Correct Answer: D

Rationale: Step-by-step rationale: 1. CRRT removes solutes and water slowly to avoid hemodynamic instability. 2. Slow removal better tolerates fluid and electrolyte shifts in critically ill patients. 3. Unlike intermittent hemodialysis, CRRT provides continuous, gentle therapy. 4. Choice A is incorrect as both CRRT and intermittent hemodialysis use a hemofilter. 5. Choice B is incorrect as CRRT does not provide faster solute and water removal. 6. Choice C is incorrect as CRRT allows for diffusion to occur, albeit at a slower rate. Summary: Continuous renal replacement therapy (CRRT) removes solutes and water slowly to prevent hemodynamic instability, making it a gentler and more continuous process compared to intermittent hemodialysis. The other choices are incorrect as CRRT does use a hemofilter, does not provide faster removal, and still allows for diffusion to occur.

Correct Answer: D

Rationale: The correct answer is D because continuous venovenous hemodiafiltration (CVVHDF) combines ultrafiltration, convection, and dialysis to maximize fluid and solute removal. Ultrafiltration removes plasma water, convection removes fluids and solutes, and dialysis facilitates solute removal through diffusion. Choice A is incorrect because convection alone does not remove solutes, but CVVHDF combines convection with other methods. Choice B is incorrect because CVVHDF is not specifically used for volume overload, although it does remove fluids. Choice C is incorrect because CVVHDF does not involve adding dialysate to remove solutes; instead, it relies on diffusion for solute removal. In summary, the correct answer D is the best choice as it encompasses all the components needed for comprehensive fluid and solute removal in CVVHDF.

Correct Answer: D

Rationale: The correct answer is D because if a reliable 24-hour urine collection is not possible, a standardized formula can be used to estimate the GFR. This is typically done using the patient's serum creatinine level, age, sex, and race. It is a validated method when direct measurement is not feasible. A: Incorrect. It is still possible to estimate GFR using formulas when 24-hour urine collection is not possible. B: Incorrect. BUN alone is not sufficient to accurately determine renal function. C: Incorrect. BUN/Creatinine ratio is not a direct measure of GFR and may be influenced by other factors.

Correct Answer: C

Rationale: The correct answer is C because the patient with acute pancreatitis receiving TPN is at risk for hyperglycemia due to the high glucose content in TPN. Monitoring blood glucose levels is crucial to prevent complications. Explanation for why other choices are incorrect: A: The 18-year-old male post-surgery for a fractured femur does not have a direct correlation to blood glucose control assessment. B: The 29-year-old female undergoing evaluation for pheochromocytoma is not directly related to blood glucose control assessment. D: The 62-year-old morbidly obese female post-hysterectomy for ovarian cancer does not specifically require immediate blood glucose control assessment.