Clinical Laboratory Hematology 3rd Edition by Shirlyn McKenzie, Lynne Williams

Exercise 13

Jerry, a 44-year-old male, arrived in the emergency room by ambulance after a bicycle accident. Examination revealed multiple fractures of the femur. He was otherwise healthy. The next day, he was taken to surgery to repair the fractures. After surgery, his hemoglobin was 7 g/dL. He refused blood transfusions and was discharged 6 days later. Jerry called his doctor within days of being discharged and told him that he had difficulty walking around the house on crutches because of shortness of breath and lack of stamina.
Consider why Jerry's hemoglobin decreased after surgery and how this could be related to his current symptoms.
After a week at home, Jerry called his doctor, who sent him back to the hospital where he was given 2 units of packed red cells. Within a day, he had more energy.
Explain why Jerry would have had more energy after the transfusions.