A nurse is caring for a client who has had an allogeneic hematopoietic stem-cell transplant. Which of the following infection-control precautions should the nurse use while caring for this client?

A. Hyponatremia: Hyponatremia is characterized by low sodium levels in the blood and can lead to symptoms such as weakness, confusion, and seizures. While hyponatremia can contribute to fluid imbalance, the client's presentation with shortness of breath, lower extremity swelling, crackles in the lungs, and elevated blood pressure is more indicative of fluid volume excess rather than hyponatremia.

B. Hypervolemia: Hypervolemia, or fluid volume excess, occurs when there is an abnormal increase in the extracellular fluid volume. This can lead to symptoms such as shortness of breath, crackles in the lungs (indicative of pulmonary edema), peripheral edema, and elevated blood pressure. Given the client's reported symptoms and assessment findings, hypervolemia is the most likely diagnosis.

C. Hypovolemia: Hypovolemia, or fluid volume deficit, occurs when there is a decrease in the extracellular fluid volume. This condition is characterized by symptoms such as thirst, dry mucous membranes, decreased urine output, and hypotension. The client in this scenario presents with signs and symptoms consistent with fluid volume excess rather than hypovolemia.

D. Hyperkalemia: Hyperkalemia is characterized by elevated potassium levels in the blood and can lead to symptoms such as muscle weakness, cardiac dysrhythmias, and nausea. While hyperkalemia can occur in clients with end-stage kidney disease, the client's reported symptoms and assessment findings are more suggestive of fluid volume excess rather than hyperkalemia.

A. Chocolate milk:
Chocolate contains caffeine, which can contribute to sleep disturbances. It is not a recommended beverage for someone looking to decrease caffeine intake.

B. Diet cola:
Cola contains caffeine, even in diet versions, which can contribute to sleep disturbances. Therefore, it is not suitable for decreasing caffeine intake.

C. Brewed iced tea:
Brewed iced tea contains caffeine, which can interfere with sleep. It is not a suitable option for someone trying to reduce caffeine consumption.

D. Lemon-lime soda:
Lemon-lime sodas typically do not contain caffeine, making them a better choice for someone looking to reduce their caffeine intake and improve sleep.