Oct. 11, 2016
For most of the last 250 years, whole blood was the only option for patients needing transfusion after surgery or major trauma. The transition from whole blood to blood that has been leukoreduced and separated into plasma, platelets and packed red blood cells (pRBCs) began in the 1970s. By 1990, component blood was used almost exclusively in trauma surgery.
This radical change in practice was driven by practicality — using component blood reduced waste, increased storage times and allowed a tailored approach to resuscitation. But the shift was unsupported by data comparing whole blood with component therapy, especially in patients needing massive transfusions. In retrospect, it became clear that transfusion guidelines, which were extrapolated from the elective surgery setting, didn't take into account the acidosis and coagulopathy associated with hemorrhagic shock.
"Most severely injured trauma patients are coagulopathic rather than anemic, which leads to worsening bleeding and worsening clinical situations," explains Martin D. Zielinski, M.D., medical director of trauma clinical research at Mayo Clinic's campus in Rochester, Minnesota.
He says component blood, even when given in a 1:1:1 transfusion ratio of platelets, plasma and RBCs — the current standard of care in the resuscitation of severe hemorrhage — doesn't contain the same levels of platelets, clotting factors and fibrinogen found in whole blood. Component blood is also anemic and acidotic and contains a "myriad of additives," including dextrose, mannitol, sodium phosphate, sodium bicarbonate, sodium chloride, citric acid, phosphate, dextrose and adenine. And because it comes from many donors, component blood may carry a higher risk of infection.
Whole blood, for its part, has the potential for incompatibility in patients with unknown blood types, but using universal donor group O blood essentially eliminates this risk. Furthermore, stored whole blood undergoes the same testing as components and is fully approved by the Food and Drug Administration (FDA) and AABB.
Despite the advantages of stored whole blood, which Dr. Zielinski and colleagues described in a 2014 article published in Surgery, he says the ideal for massive hemorrhage remains warm fresh whole blood (WFWB). Transfused within minutes to 24 hours of collection, it most closely resembles the blood patients are losing. Data support this idea. From 2003 to 2007 in Iraq and Afghanistan, more than 500 soliders with life-threatening injuries were transfused with WFWB. Those patients showed better 48-hour and 30-day survival compared with massively hemorrhaging patients who received stored red blood cells.
Moving toward a WFWB transfusion program
Dr. Zielinski's long-term goal is to have the nation's first WFWB transfusion program for hemorrhaging patients — something that may become critically important when large-scale disasters such as Hurricane Katrina disrupt normal blood product distribution. But implementing such a program presents huge logistical challenges. Fresh blood is more likely to transmit infections such as HIV and hepatitis C because it can't be tested before transfusion. And it is not approved for civilian use by the FDA or AABB. The only military indications are a short supply of whole-blood components or the failure of a 1:1:1 transfusion ratio resuscitation.
Dr. Zielinski and colleagues at Mayo Clinic say there is overwhelming evidence — and fewer challenges — supporting the use of group O stored whole blood for massively hemorrhaging patients. Thus, the intermediate step has been to establish a stored whole-blood transfusion program at Mayo Clinic's campus in Minnesota, which currently stores up to four units of whole blood for about 10 days. Since the program's implementation in February 2016, several patients have been transfused, all very successfully, Dr. Zielinski says.
Only three other centers in the country provide whole-blood transfusions for massive hemorrhages, mainly because of the logistics and costs involved.
"You have to create a process with the blood bank, which is highly regulated to ensure best practices are followed; there is definitely an initial hump to get over before all the details are worked out," Dr. Zielinski explains. "The vast majority of rural hospitals don't have the capability to have a blood bank to tailor blood products for hemorrhaging patients, so it's important to have trauma centers capable of doing these things."
For more information
Zielinski MD, et al. Back to the future: The renaissance of whole-blood transfusions for massively hemorrhaging patients. Surgery. 2014;155:883.