Many surgeons put their patients in harm's way by transfusing far more blood than necessary for good outcomes, and incurring enormous and avoidable expenses for their hospitals and for society—as much as $1,100 per unit.
That's according to a study of highly variable use of blood and components by surgeons who operated on nearly 3,000 patients at Johns Hopkins Hospital between February, 2010 and August, 2011. The research paper was published in the April issue of the journal Anesthesiology.
Current research says transfusions for most surgeries should not be initiated until the patient's hemoglobin level—normally 12 to 14—has dropped to 6 or 7 grams per deciliter (g/dl). A level of 7 or 8 is considered safe.
But the recommendations of three specialty societies that guide current practice leave the trigger point in question. "They say that if a patient's hemoglobin level is less than 7 g/dl, then the patient would benefit from a blood transfusion. But if it's greater than 10, they would not benefit. But they don't say what should be done if the level is between 7 and 10," Steven M. Frank, MD, leader of the study, said during an interview.
Thus, many surgeons initiate transfusion when levels are at 10, while others start at 9 or 10 or 11. Additionally, surgeons vary in the target point at which they stop transfusing. Some stopping at 11 or 12, even though they could stop at 10.
"There [have] been four big randomized trials and they all four have shown no difference between overall outcome between thresholds of 8 and 10," Frank said. "Yet even though they show no difference, people in medicine are still using 10 as the threshold, even though 8 is just as good."
The biggest study to date was published in December by the FOCUS research group (Functional Outcomes in Cardiovascular Patients Undergoing Surgical Hip Fracture Repair), Frank explained. "Those researchers found that by lowering hemoglobin threshold to 8 (instead of) 10, they used 66% fewer blood transfusions and they had no different outcomes between the two groups in length of stay, heart attack, stroke, death, and even the ability to walk," Frank said.
"Their conclusion was that if there's no benefit from giving extra blood, then all (that's left is the additional) cost and the potential for harm by giving more blood than is needed."
In their latest paper in Anesthesiology, Frank and his co-authors quantified the transfusion practices for each of 44 Johns Hopkins surgeons, and then compared their use of blood by type of patient and type of procedure. For example, they found that among four surgeons performing the Whipple procedure, there was a 1.8 g/dl difference between the point at which a transfusion was initiated, and a 1.9 g/dl difference between the highest and lowest target levels at which transfusions were stopped.
Other procedures in which there was great variation in either the hemoglobin "trigger" and/or the hemoglobin "target" were posterior lumbar fusion, and primary coronary artery bypass grafts.
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.
Frank said that the practice variation results because doctors "are trained to a certain practice, and once they finish their training they are slow to adapt. A lot of these studies with lower thresholds have come out in the last few years and some surgeons just aren't familiar with them."
He added that because the blood banking system has dramatically improved its ability to screen donors for hepatitis or HIV infected blood, "a lot of doctors assume that blood is completely safe, and that's the main risk they used to worry about. But there are many other risks besides that which people don't think about," such as allergic reactions to blood.
Another researcher in this project, Paul Ness, MD, said that studies like this one "help to drive hospitals to start to confront some of this. They provide support to start some of these programs (to reduce the unnecessary use of blood). Blood costs are expensive. And in this era where Medicare and Medicaid are trying to reduce payments to hospitals and doctors, all of these elements can work together."
See Also:
National Effort Scrutinizes Costly Blood Transfusion Complications
Why Aren't Hospitals More Concerned About Blood Safety?