Additionally, the amounts of blood each patient received did not seem based on their level of illness, or with how much blood is typically lost in that type of surgery.
Settings in which patients are suffering a traumatic injury or are hemorrhaging, which blood loss can be fast and profound, are exceptions, to the rule, Frank says.
The solution to the problem at Johns Hopkins wasn't a difficult one, Frank said. The researchers talked to the doctors who used the most blood, and their behavior began to change. One doctor who previously transfused 30% of his patients subsequently transfused only 18%.
Frank says that since his report, he's talked with fellow surgeons at other large institutions around the country. "I can say that in general, patients are given more blood than is necessary," based on what we know is safe, he said.
Transfusions carry numerous risks. Patients may develop allergic reactions to donor blood; they may develop antibodies after the transfusion which makes it more difficult to find a match should they need another transfusion later in life; and transfusions make patients more susceptible to infections such as sepsis and pneumonia, because blood components suppress the immune system.
There also is a 42% increased risk of cancer recurrence in cancer patients who were transfused during cancer surgery, Frank said.
And blood is expensive. Although it costs $278 to buy a unit from the American Red Cross, Frank pointed to research that evaluated the cost incurred by every step along the blood delivery route, including transportation, viral testing, cold storage, blood typing, and found that it amounted to more than $1,100 per unit. Most of those costs are absorbed by the hospital.