Correct Answer: C

Rationale: The correct instruction is to take ferrous sulfate on an empty stomach to increase absorption. This is because taking it with food or dairy products like milk can reduce its absorption. Orange juice is not recommended as it may interfere with the absorption of iron. Taking ferrous sulfate on an empty stomach may cause gastrointestinal upset, but this can be minimized by gradually increasing the dose.

Correct Answer: A

Rationale: When a patient refuses a newly opened fentanyl patch, the nurse should ask another nurse to witness the disposal of the new patch. This action ensures accountability, proper protocol, and prevents any potential diversion or misuse of the medication. Disposing of the patch in a sharps container (Choice B) is not sufficient as it does not address the need for witness accountability. Sending the patch back to the pharmacy (Choice C) may not be appropriate without proper documentation and witness. Simply documenting the refusal and removing the patch (Choice D) may lack the necessary verification of proper disposal.

Correct Answer: A

Rationale: Placing a pillow between the client's legs is the correct action to prevent dislocation of the prosthesis after hip arthroplasty. This positioning helps maintain proper alignment and stability of the hip joint, reducing the risk of dislocation. Placing the client in a high Fowler's position (choice B) is not recommended after hip arthroplasty as it may strain the hip joint. Maintaining the client in a side-lying position (choice C) or keeping the client's legs elevated (choice D) does not provide the same level of support and alignment as placing a pillow between the legs.

Correct Answer: C

Rationale: A platelet count of 90,000/mm³ indicates thrombocytopenia, which increases the risk of bleeding and requires immediate intervention. Thrombocytopenia can lead to serious bleeding complications, so it is crucial to address this finding promptly. A low white blood cell count (choice A) may indicate neutropenia but is not as immediately life-threatening as severe thrombocytopenia. A hemoglobin level of 8 g/dL (choice B) would require intervention but is not as urgent as addressing a critically low platelet count. A serum potassium level of 3.5 mEq/L (choice D) is on the lower side of normal but does not pose an immediate risk to the client's safety compared to severe thrombocytopenia.

Correct Answer: A

Rationale: A glomerular filtration rate (GFR) of 14 mL/min is significantly low, indicating poor kidney function and the need for hemodialysis to remove waste products effectively. BUN, serum magnesium, and serum phosphorus levels are important in assessing kidney function and electrolyte balance but are not direct indicators for the initiation of hemodialysis. BUN (blood urea nitrogen) reflects the kidney's ability to filter waste products, serum magnesium levels are important for muscle and nerve function, and serum phosphorus levels are vital for bone health.