A nurse is assessing a client's history before a blood transfusion. Which condition should the nurse identify as a contraindication for transfusion?

A) Incorrect: A slight increase in blood pressure is not a significant vital sign alteration that requires immediate reporting before initiating the transfusion. It could be related to various factors, such as anxiety or pain.

B) Incorrect: A respiratory rate of 22 breaths per minute is within the normal range for an adult and does not require immediate reporting before starting the transfusion.

C) Incorrect: A decrease in heart rate from 88 to 72 beats per minute is not a critical vital sign alteration. As long as the heart rate remains within the client's baseline range, it does not need immediate reporting.

D) Correct: An elevated temperature of 38.5°C (101.3°F) may indicate a fever, which could be a sign of an infection or an adverse reaction to the transfusion. The nurse should report this vital sign alteration to the healthcare provider before proceeding with the transfusion to determine the appropriate course of action.

A) Correct: Pre-medicating the client with antihistamines before the transfusion can help prevent or minimize allergic transfusion reactions in clients with a history of severe allergies. Antihistamines block histamine release, reducing the risk of allergic symptoms.

B) Incorrect: Administering the blood transfusion rapidly is not a preventive measure for allergic transfusion reactions. In fact, rapid administration may increase the risk of adverse reactions.

C) Incorrect: Warming the blood product before administration is important to prevent hypothermia but is not directly related to preventing allergic transfusion reactions.

D) Incorrect: Monitoring the client's vital signs during the transfusion is a standard practice, but it is not the primary intervention for preventing allergic transfusion reactions. Pre-medication with antihistamines is a more targeted approach.