Nov. 11, 1999 (Indianapolis) -- Although the main treatment for trauma patients who have lost too much blood is to stop the bleeding, doctors continue to look for better ways to replace these losses and keep the patient alive long enough to get to surgery. An article appearing in the Nov. 17 edition of The Journal of the American Medical Association (JAMA) reports on diaspirin cross-linked hemoglobin (DCLHb), a type of blood replacement fluid, and how it does not appear to be effective for this use.
DCLHb is a purified and modified form of human hemoglobin, the substance in red blood cells that carries oxygen throughout the body. Unlike most current treatments, which increase the volume of the blood without increasing its ability to carry oxygen, it was hoped DCLHb's ability to carry oxygen would improve outcomes in patients with severe traumatic shock from blood loss. Another advantage is that DCLHb, unlike blood, would not have to be matched to a patient's blood type. Finally, it is much easier to store DCLHb than most other blood products.
Shock is a state in which the heart is unable to deliver oxygen and other nutrients to the body to function properly. This inability to deliver is often due to loss of blood. Many trauma patients experience some degree of shock. If untreated, shock can lead to failure of the heart and other organs and eventually can lead to death.
In this study, the researchers looked at about 110 trauma patients admitted to 18 trauma centers. All patients were given an intravenous (IV) infusion of DCLHb or a similar amount of saline, a saltwater solution.
Critically ill patients could get another dose of DCLHb if needed. Four weeks later, both illness and death rates were significantly higher among those given DCLHb. The study was originally designed to include a total of 850 trauma patients, but because of such poor results with DCLHb and concerns about proper patient care, the study was suspended early.
"The results were very disappointing to us," says lead author Edward P. Sloan, MD, associate professor of emergency medicine at the University of Illinois, Chicago, in an interview with WebMD. "That was a result that we were not expecting based on earlier preclinical results."
Lt. Col. David Burris, MD, chief of the division of surgical research at the Uniformed Services University of the Health Sciences in Bethesda, Md., found this to be an interesting study. "Many of us would like to see a fluid that doesn't need typing [matching to a persons blood type], that has no storage problems, and won't spread infections," says Burris, who was not involved in study. "Trauma trials, especially with survival as the endpoint, are very difficult. The nature of trauma makes it hard to get uniform groups to study. We often end up comparing the patient who may have a small amount of injury in one area to the car accident victim who may literally be injured from head to toe."
J. Wayne Meredith, MD, professor of surgical sciences and chairman of general surgery at the Wake Forest University School of Medicine in Winston-Salem, N.C., notes that stopping the bleeding is really the only way to successfully treat patients who are in shock. Under the best of circumstances, products such as DCLHb will only help keep the person alive a little longer and increase their chances of getting to surgery.
"The main thing for the general public to remember is to donate blood," says Meredith. "Although we are trying to find ways to extend, or even replace blood supplies, this study shows we are not there yet. Making sure adequate supplies of blood are on hand remains the best way to treat hemorrhagic shock [in trauma patients]."