Using reconstituted blood — packed red cells and fresh-frozen plasma that are mixed in the operating room just before use — for heart bypass surgery in infants works better than using fresh whole blood, researchers have found. Babies who received the reconstituted blood during surgery to repair congenital heart defects on average had shorter stays in the intensive care unit and spent less time on mechanical ventilation after surgery than babies who received fresh whole blood — blood that is less than 48 hours old and whose red cells and plasma have not been separated.
Reconstituted blood is better for infants’ heart surgery than fresh blood
Using reconstituted blood — packed red cells and fresh-frozen plasma that are mixed in the operating room just before use — for heart bypass surgery in infants works better than using fresh whole blood, researchers at UT Southwestern Medical Center at Dallas and Children’s Medical Center Dallas have found.
Babies who received the reconstituted blood during surgery to repair congenital heart defects on average had shorter stays in the intensive care unit and spent less time on mechanical ventilation after surgery than babies who received fresh whole blood — blood that is less than 48 hours old and whose red cells and plasma have not been separated.
The findings, which appear in today’s New England Journal of Medicine, put to rest a decades-long debate in the medical community, said Dr. Daniel Stromberg, assistant professor of pediatrics at UT Southwestern and the study’s senior author.
”The results demonstrate that the current national opinion regarding the benefits of fresh whole blood is incorrect,” said Dr. Stromberg, who is also a cardiologist at Children’s. ”Fresh whole blood priming of the cardiopulmonary bypass circuit is actually worse in terms of clinical outcomes. This is important for patients and for blood banks — potentially saving lots of money and preserving component inventory.”
During heart surgery, babies must be placed on a cardiopulmonary bypass machine, which does the work of the heart and lungs while surgeons make repairs. The machine must be primed with donor blood because babies do not have enough of their own blood to supply both the machine and their tiny bodies. Blood priming of the cardiopulmonary bypass machine is not necessary for adults, whose blood volume is larger.
Traditionally, surgeons have insisted on using fresh whole blood to prime the bypass machine and would even cancel procedures when it wasn’t available. Using reconstituted blood would ease blood centers’ burden of meeting the demand for whole blood, researchers said. Physicians estimate that 19,000 operations for congenital heart disease are performed annually in the United States, with the majority requiring cardiopulmonary bypass.
One benefit of using fresh whole blood in the cardiopulmonary bypass machine was that the patient’s donor exposure was decreased: one donor as compared to two donors with the reconstituted blood. That risk could be easily minimized by using both components of reconstituted blood from the same donor, Dr. Stromberg said.
Reconstituted blood also costs slightly more initially than fresh blood. but the overall savings from reconstituted blood use during recovery could be thousands of dollars. During the study, babies who received the reconstituted blood for heart surgery left the cardiac ICU roughly 25 percent quicker than those getting fresh blood (70.5 hours to 97 hours) and spent 31 percent less time on mechanical ventilation following surgery (36.3 hours to 53 hours). The reconstituted blood group also demonstrated less accumulation of fluid 48 hours after surgery (-6.9 milliliter per kilogram of body weight to 28.8 ml/per kg).
Researchers studied 200 patients during a four-year period at Children’s; participants were younger than 1 year old with congenital heart defects that required open heart surgery to repair. Patients were randomly assigned to receive fresh whole blood or reconstituted blood during surgery. All blood products used were acquired from a standard donor pool and underwent routine screening for infectious agents, as required by the Food and Drug Administration. All care providers, except for the operating room perfusionist and circulating nurse — who monitor and operate equipment that oxygenates the blood during open heart surgery, were blinded to the patient’s group assignment.
Other UT Southwestern researchers who participated in the study were Dr. Steven Mou, a fellow in the pediatric intensive care unit; Dr. Brett Giroir, professor of pediatrics; Dr. Erica Molitor-Kirsch, assistant professor of pediatrics; Dr. Steven R. Leonard, professor of cardiovascular and thoracic surgery; Dr. Hisashi Nikaidoh, professor of cardiovascular and thoracic surgery; and Dr. William Scott, professor of pediatrics. Deborah Town, a nurse and clinical research coordinator at Children’s; Dr. Lonnie Roy, biostatistician and senior planning analyst in Children’s market research department; and Dr. Frank Nizzi of Carter BloodCare in Dallas were also involved in the study.