Blood salvaged and reused on a patient undergoing heart surgery appears to be healthier than blood obtained from a blood bank, according to a new study.
Steven Frank, MD, and a team of researchers from Johns Hopkins University School of Medicine, found that the more blood from a blood bank a patient was given, the more there was red blood cell damage.
This, researchers said, “renders the cells less flexible and less able to squeeze through a body’s smallest capillaries and deliver oxygen to tissues.”
For patients who were given five or more units of blood bank blood, the damage to the cells was evident “for at least three days after surgery.”
This, the researchers say, could increase the risk of “hospital-acquired infections, longer hospital stays and increased risk of death.”
“We now have more evidence that fresh blood cells are of a higher quality than what comes from a blood bank,” said Frank, an associate professor of anesthesiology and critical care medicine at Johns Hopkins in a statement
“If banked blood, which is stored for up to six weeks, is now shown to be of a lower quality, it makes more sense to use recycled blood that has only been outside the body for one or two hours,” he added. “It’s always been the case that patients feel better about getting their own blood, and recycling is also more cost effective.”
Blood salvaging or recycling first become used commonly during the HIV/AIDS crisis, but even though the blood supply is much safer now, Frank says the focus should be on salvaging because “fresher blood is better.”
The process of salvaging blood involves a machine called a cell saver. Blood collected from a patient undergoing surgery is collected and washed of fat and other unneeded tissue. Then the machine separates the red cells, which are given back to the patient.
Researchers said using recycled blood is more cost effective than using blood from a bank.
The American Association of Blood Banks (AABB), an international non-profit association representing individuals and institutions involved in the field of transfusion medicine, called the study another part of the “transfusion medicine puzzle.”
“It’s clearly a viable alternative treatment,” said AABB’s Eduardo Nunes, senior director of standards, advocacy and patient blood management, adding that with some patients, most notably those who have experienced trauma, transfusions are the only viable option.
“Even though it’s a small study, it suggests the benefit of avoiding a transfusion if it can be,” said Nunes. “There do seem to be changes to what happens to banked blood over a long enough time.”
The Hopkins study was small, and focused only on 32 patients undergoing cardiac surgery. Twelve of the patients were given only their own recycled red blood cells, while 10 were given their own blood and fewer than five units of banked blood and 10 received some of their own blood and more than five units of banked blood.
Each was given a blood test before, during and after surgery to check how well the blood was carrying oxygen.
The researchers said that the more blood the patient received from a blood bank, the poorer the blood’s capability to carry oxygen was. In patients who received only their blood, the blood cells performed normally “right away.” Those who received the most bank blood had not recovered full blood function three days after surgery.
“If something is bad for you, a little bit might be OK, but a lot of it is much worse,” Frank said. “It turns out that blood is more like milk, which has a relatively short shelf life, than a fine wine, which gets better with age.”
Blood salvaging is not an appropriate procedure for all surgeries, Frank said. Some hospitals are not always staffed with the right personnel to run the equipment, he said. But more importantly, not all surgeries cause enough blood loss to warrant the use of a cell saver.
Frank said he would recommend using recycled blood in any procedure in which a doctor might give one or more units of blood.
The process could have major benefits in the developing world, Frank said in an email to VOA, citing the greater risk of HIV or hepatitis transmission.
“There is also a huge shortage of blood in these countries,” he said. “If there were only the resources to purchase the equipment to make blood salvage more available, then this technology would be more widely utilized.”
Frank said the next step to making blood salvaging more widespread is to raise awareness among doctors about what surgical procedures “yield enough of this higher quality recycled blood to outweigh the costs of using the device.”
“This appears to be any procedure where one or more units of blood will be required for transfusion,” he said. “Blood salvage, or recycling is common in cardiac surgery but is underutilized in most other surgical specialties. Orthopedics, vascular, trauma, and transplant surgeries are those that benefit most outside of cardiac surgery."
The study appears in the June issue of the journal Anesthesia & Analgesia