Credit: UAB Hospital
Reinfusing the blood a patient loses during cardiopulmonary bypass surgery confers benefits over transfusing the patient with banked blood, results of a small study suggest.
Investigators noted that both the surgery and red blood cell (RBC) storage are associated with changes in RBCs that can adversely affect oxygen delivery.
However, their study revealed minimal effects on RBC structure and function among patients who received their own recycled blood during surgery.
On the other hand, patients who received banked RBCs along with their own blood experienced a dose-dependent decrease in RBC cell membrane deformability that could persist beyond 3 days.
Steven Frank, MD, of the Johns Hopkins University School of Medicine in Baltimore, Maryland, and his colleagues reported these findings in Anesthesia & Analgesia.
The team studied 32 patients undergoing cardiopulmonary bypass, categorizing them by their transfusion status: those who received their own RBCs (n=12), those who received their own blood plus fewer than 5 units of banked blood (n=10), and those who received their own RBCs plus 5 or more units of stored blood (n=10).
All patients had blood samples drawn before, during, and for 3 days after surgery. The investigators examined samples for blood cell membrane stiffness and flexibility.
In patients who received only their own recycled blood, their cells behaved normally right away, as if they had never been outside the body.
But the more banked blood a patient received, the less flexible their entire population of RBCs. Three days after surgery, RBCs in the group that received the largest number of transfused units still had not recovered their full function.
“We now have more evidence that fresh blood cells are of a higher quality than what comes from a blood bank,” Dr Frank said.
“If banked blood, which is stored for up to 6 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 1 or 2 hours. It’s always been the case that patients feel better about getting their own blood, and recycling is also more cost-effective.”
The investigators used a cell saver machine to collect the material a patient lost during surgery. They then rinsed away the unneeded fat and tissue, centrifuged and separated the red cells, and returned them to the patient.
Dr Frank and his colleagues noted that disposable parts of the cell saver, which can be used to process multiple units of blood, cost around $120, compared to $240 for each unit of banked blood. Additionally, recycling blood reduces a patient’s risk of contracting infections and experiencing transfusion-related adverse reactions.
Dr Frank pointed out, however, that cell saver machines are not appropriate for all operations, and not all hospitals have access to round-the-clock perfusionists to run them. For heart surgeries, a perfusionist is already in the operating room to run the heart-lung bypass machine.
Dr Frank also noted that many operations are considered to be a low risk for blood loss, in which case, the cell saver is unnecessary. Nevertheless, he advocates wider use of recycled blood.
“In any patient where you expect to give 1 unit of red blood cells or more, it’s cost-effective and beneficial to recycle,” he said.
