Friday, April 25, 2008
University of Maryland Shock Trauma Center Study Differs from Battlefield Data
Recent data from military physicians treating battlefield injuries in Iraq suggests that giving one unit of fresh frozen plasma along with each unit of red blood cells would reduce mortality in patients with excessive bleeding. As a result, many civilian trauma centers have begun to adopt that regimen rather than giving red blood cells alone. However, a University of Maryland study of more than 800 critically injured trauma patients in Baltimore concludes that early and aggressive administration of fresh frozen plasma does not improve patient outcome.
"Based on the data from the battlefield, we all assumed that adding fresh frozen plasma might be a good idea. But we decided to look at it carefully and we found no difference in mortality," says Thomas Scalea, M.D., lead author of the study and physician-in-chief of the R Adams Cowley Shock Trauma Center, which is part of the University of Maryland Medical Center. The study results will be presented at the 128th annual meeting of the American Surgical Association in New York on April 25, 2008.
"Our study sounds a note of caution, because there is an increased risk of complications
when patients receive additional blood products. There is also a cost issue," says Dr. Scalea, who is also professor of surgery and director of the Program in Trauma at the University of Maryland School of Medicine.
Fresh frozen plasma comes from human blood. The plasma is separated from the red blood cells and is frozen solid within six hours after the blood has been collected. It is most commonly used to treat problems with blood clotting or coagulation. There are risks to the therapy, including allergic reactions, lung injury and the possibility of acquiring an infection, which is a risk that comes with receiving any blood products.
The University of Maryland study included 806 critically injured patients who were admitted to intensive care at the Shock Trauma Center from July 2004-November 2006. Most of the patients, 77 percent, were male, and 85 percent had sustained blunt injuries, such as from vehicle crashes. About 45 percent of the patients received blood transfusions within the first 24 hours of their admission, and 68 percent were given a combination of both red blood cells and fresh frozen plasma.
The researchers found that after controlling for all relevant variables among the patients, including age, gender, type of injury and length of stay in intensive care, there was no significant difference in outcome between the patients who had received one unit of fresh frozen plasma for every unit of red blood cells and those who were given the red blood cells alone. The overall mortality for these critically injured patients in the study was four percent, mainly due to lethal brain injuries or death immediately upon arrival to the trauma center.
"There may be differences between civilian and combat-injured patients that would explain why our study found no benefit to the early and aggressive use of fresh frozen plasma," says Dr. Scalea. "Some patients may benefit from the combination, but we need to figure out who they are with further study. Based on our research, widespread use of this protocol, which would clearly impact blood bank resources around the country, does not seem justified."