A nurse is assessing a client who is receiving one unit of packed red blood cells to treat intraoperative blood loss. The client reports chills and back pain, and the client’s blood pressure is 80/64 mm Hg. Which of the following actions should the nurse take first?

Choice A reason: The first action in suspected transfusion reaction is to stop the blood transfusion immediately to prevent further exposure to the antigen causing the reaction. This is a priority to reduce the risk of hemolysis and shock. Choice B reason: Notifying the laboratory is important for follow-up and investigation, but it is not the first action. It should be done after stopping the transfusion. Choice C reason: Obtaining a urine specimen is part of the protocol to assess for hemoglobinuria, but it is not the immediate priority. Choice D reason: Informing the provider is necessary, but only after the transfusion has been stopped to prevent further harm.