Expected Hemoglobin Increase from PRBCs

A 75-year-old female patient is admitted to the hospital with severe anemia and is scheduled to receive a blood transfusion. The patient's baseline hemoglobin level is 7 g/dL, and the physician orders one unit of packed red blood cells (PRBCs) to be transfused. Before starting the transfusion, the nurse needs to calculate the expected increase in hemoglobin levels after the transfusion based on the volume of one unit of PRBCs.

It is known that one unit of PRBCs can increase hemoglobin levels by approximately ____ g/dL. Fill in the blank with the expected increase in hemoglobin levels after administration of one unit of PRBCs.