a nurse is taking care of two clients who have a prescription to receive a blood transfusion of packed red blood cells at the same time. the first client's blood pressure dropped from the preoperative value of 120/80 mm hg to a postoperative value of 100/50 mm hg. the second client is hospitalized because he developed dehydration and anemia following pneumonia. after checking the patency of their iv lines and vital signs, what should the nurse do next?