A patient receiving a unit of blood complains of feeling cold and begins to have shaking chills. What is the nurse's first action?

When a patient receiving a blood transfusion reports feeling cold and begins to experience shaking chills, this may be indicative of a transfusion reaction, which can pose serious risks to the patient. The immediate and appropriate response in this scenario is to stop the transfusion. Stopping the transfusion ensures the patient's safety by preventing further exposure to potentially harmful blood components and allows the healthcare team to assess the situation and provide necessary interventions.

By halting the transfusion, the nurse can initiate protocols to manage the patient's symptoms and prevent complications. Following this immediate action, further assessments and interventions can be carried out, such as notifying the physician to arrange for further evaluation and treatment, as well as monitoring vital signs for any changes that may occur as a reaction unfolds.