Continuous venovenous hemodialysis is used to
- A. remove fluids and solutes through the process of convection.
- B. remove plasma water in cases of volume overload.
- C. remove plasma water and solutes by adding dialysate.
- D. combine ultrafiltration, convection and dialysis Continuous venovenous hemodialysis (CVVHD) is similar to CVVH in that ultrafiltration removes plasma water. It differs in that dialysate solution is added around the hemofilter membranes to facilitate solute removal by the process of diffusion. Continuous venovenous hemofiltration (CVVH) is used to remove fluids and solutes through the process of convection. Slow continuous ultrafiltration (SCUF) is also known as isolated ultrafiltration and is used to remove plasma water in cases of volume overload. Continuous venovenous hemodiafiltration (CVVHDF) combines ultrafiltration, convection, and dialysis to maximize fluid and solute removal.
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.
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A patient with pancreatic cancer has been admitted to the critical care unit with clinical signs consistent with syndrome of inappropriate secretion of antidiuretic hormone. The nurse anticipates that clinical management of this condition will include
- A. administration of 3% normal saline.
- B. administration of exogenous vasopressin.
- C. fluid restriction.
- D. low sodium diet.
Correct Answer: C
Rationale: Step 1: Syndrome of inappropriate antidiuretic hormone (SIADH) leads to excess water retention, diluting sodium levels in the blood.
Step 2: Fluid restriction is the mainstay of treatment to prevent further dilution of sodium.
Step 3: Administering 3% normal saline (choice A) can worsen the condition by further increasing sodium levels.
Step 4: Exogenous vasopressin (choice B) would exacerbate the problem by increasing water retention.
Step 5: Low sodium diet (choice D) may be beneficial in the long term but is not the immediate priority.
A patient with type 1 diabetes who is receiving a continuous subcutaneous insulin infusion via an insulin pump contacts the clinic to report mechanical failure of the infusion pump. The nurse instructs the patient to begin monitoring for signs of:
- A. adrenal insufficiency.
- B. diabetic ketoacidosis.
- C. hyperosmolar, hyperglycemic state.
- D. hypoglycemia.
Correct Answer: B
Rationale: The correct answer is B: diabetic ketoacidosis. When an insulin pump fails, the patient may experience a sudden decrease in insulin delivery, leading to a potential rise in blood glucose levels. This can trigger diabetic ketoacidosis, characterized by hyperglycemia, ketosis, and acidosis. Monitoring for signs such as increased thirst, frequent urination, fruity breath odor, and rapid breathing is crucial.
Incorrect choices:
A: Adrenal insufficiency is not directly related to insulin pump failure.
C: Hyperosmolar, hyperglycemic state is more common in type 2 diabetes and typically occurs with extreme hyperglycemia, not sudden pump failure.
D: Hypoglycemia is less likely with pump failure due to decreased insulin delivery.
The patient has a temporary percutaneous catheter in place for treatment of acute kidney injury. The catheter has been in place for 5 days. The nurse should
- A. prepare to assist with a routine dialysis catheter change.
- B. evaluate the patient for signs and symptoms of infection.
- C. teach the patient that the catheter is designed for long-term use.
- D. use one of the three lumens for fluid administration.
Correct Answer: B
Rationale: The correct answer is B: evaluate the patient for signs and symptoms of infection. After 5 days, infection risk increases. Signs of infection include fever, redness, swelling, and tenderness at the catheter site. Monitoring for these signs is crucial to prevent complications. A: Routine dialysis catheter change is not indicated after 5 days. C: Teaching long-term use is incorrect as temporary catheters are not meant for extended use. D: Using lumens for fluid administration can increase infection risk and is not recommended.
Renin plays a role in blood pressure regulation by
- A. activating the renin-angiotensin-aldosterone cascade.
- B. suppressing angiotensin production.
- C. decreasing sodium reabsorption.
- D. inhibiting aldosterone release.
Correct Answer: A
Rationale: The correct answer is A because renin activates the renin-angiotensin-aldosterone cascade. Renin is released by the kidneys in response to low blood pressure or low sodium levels. It acts on angiotensinogen to form angiotensin I, which is then converted to angiotensin II by angiotensin-converting enzyme. Angiotensin II causes vasoconstriction, leading to increased blood pressure, and stimulates aldosterone release, promoting sodium and water retention.
Choice B is incorrect because renin does not suppress angiotensin production; it actually initiates the process. Choice C is incorrect because renin's action leads to increased sodium reabsorption by stimulating aldosterone release. Choice D is incorrect because renin does not inhibit aldosterone release; it promotes it as part of the renin-angiotensin-aldosterone cascade.
Which of the following patients is at the greatest risk of developing acute kidney injury? A patient who
- A. has been on aminoglycosides for the past 6 days
- B. has a history of controlled hypertension with a blood pressure of 138/88 mm Hg
- C. was discharged 2 weeks earlier after aminoglycoside therapy of 2 weeks
- D. has a history of fluid overload as a result of heart failure
Correct Answer: C
Rationale: The correct answer is C because the patient was recently discharged after a prolonged course of aminoglycoside therapy, which is a known risk factor for acute kidney injury due to its nephrotoxic effects. Choice A is incorrect because although aminoglycosides can cause kidney injury, the duration of therapy is shorter in this case. Choice B is incorrect because controlled hypertension is not a significant risk factor for acute kidney injury. Choice D is incorrect because fluid overload from heart failure may lead to other complications but is not directly associated with acute kidney injury.