clinical skills exam questions

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: C

Rationale: The correct answer is C: Potassium. During treatment of diabetic ketoacidosis, as blood glucose levels decrease, potassium levels can quickly drop due to insulin therapy driving potassium into cells. Monitoring potassium levels closely is crucial to prevent hypokalemia, which can lead to life-threatening cardiac arrhythmias. Choice A: Calcium - Calcium levels are not typically affected by diabetic ketoacidosis treatment and do not require immediate monitoring in this context. Choice B: Chloride - Chloride levels are usually not significantly impacted by diabetic ketoacidosis treatment and do not need close monitoring in this case. Choice D: Sodium - While sodium levels can be affected by dehydration in diabetic ketoacidosis, they are not as critical to monitor as potassium levels during treatment.

Correct Answer: B

Rationale: The correct answer is B: fluid replacement with 0.45% saline. The patient's symptoms suggest dehydration and hypovolemia, indicated by low blood pressure, elevated heart rate, and lack of urine output. Fluid replacement with isotonic saline would help restore intravascular volume and improve blood pressure. Blood transfusion (A) is not indicated without evidence of significant blood loss. Inotropic agents (C) are used to improve cardiac function, which is not the primary issue in this case. Antiemetics (D) may help with nausea and vomiting but do not address the underlying cause of hypovolemia.

Correct Answer: B

Rationale: The correct answer is B: Assess the patient's lungs. In rhabdomyolysis, muscle breakdown releases myoglobin which can cause kidney damage. Mannitol is given to prevent kidney damage by promoting diuresis. However, mannitol can also cause fluid overload and pulmonary edema. Therefore, assessing the patient's lungs is crucial to monitor for signs of fluid overload and prevent complications. A: Assessing the patient's hearing is not directly related to the management of rhabdomyolysis and mannitol administration. C: Decreasing IV fluids after administering a diuretic like mannitol can lead to inadequate fluid resuscitation and worsening kidney injury. D: Giving extra doses before radiological contrast agents is not necessary in the context of rhabdomyolysis and mannitol administration.

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.