Which location is the area where the highest percentage of sodium and water are resorbed back into the bloodstream?

Correct Answer: B

Rationale: The highest percentage of sodium and water resorption back into the bloodstream occurs in the proximal tubule of the nephron. The proximal tubule is responsible for reabsorbing about 65-75% of the filtered sodium and water, along with various other solutes. It has a high density of microvilli, which increases its surface area for efficient reabsorption. Additionally, the proximal tubule plays a vital role in maintaining the body's fluid and electrolyte balance by reclaiming essential substances from the filtrate before it moves further along the nephron.

Correct Answer: D

Rationale: Taking niacin with a full glass of water on an empty stomach can help reduce the risk of flushing or pruritus, which are common side effects of niacin. Additionally, starting with a low initial dose and increasing gradually as tolerated can also help minimize these side effects. Niacin can cause vasodilation, leading to flushing and itching, so taking it with water and on an empty stomach can help alleviate these symptoms.

Correct Answer: B

Rationale: The nurse monitors the aPTT to check the effectiveness of heparin therapy in preventing and treating blood clots. Heparin acts by inhibiting the clotting cascade, specifically by enhancing the activity of antithrombin III, which inactivates clotting factors such as thrombin and factor Xa. The aPTT measures the intrinsic pathway of the clotting cascade, which is affected by heparin therapy. By monitoring the patient's aPTT levels, the nurse can ensure that the patient is within the therapeutic range for heparin therapy to be effective in preventing further clot formation. Monitoring bleeding times, PT/INR, or vitamin K levels is not typically done to assess heparin therapy effectiveness.

Correct Answer: C

Rationale: Valproate belongs to the category class of anticonvulsants, which are medications primarily used to treat seizures and epilepsy. Valproate is also used as a treatment for vascular headaches, such as migraines. It is not categorized as an anticoagulant, antianxiety medication (such as benzodiazepines), or a mood stabilizer.

Correct Answer: C

Rationale: A month after receiving a blood transfusion, the development of a fever in an immunocompromised patient can be indicative of graft-versus-host disease (GVHD). GVHD is a condition where the donor immune cells attack the recipient's tissues, manifesting as fever, rash, liver dysfunction, and gastrointestinal symptoms. It typically occurs a few weeks to several months after a blood transfusion, especially in immunocompromised individuals. An allergic response to medication or myelosuppression would typically present earlier after the transfusion, while nothing related to the blood transfusion does not explain the fever in this context.