A liberal red blood cell (RBC) transfusion strategy to aggressively treat moderate anemia (when the hemoglobin level was 10 g/dl or less) in elderly surgical patients didn’t provide significantly better cardiovascular outcomes as compared to a restrictive transfusion strategy (transfusing only those symptomatic from anemia or hemoglobin level less than 8 g/dL), researchers reported in a late-breaking clinical trial presentation at the American Heart Association’s Scientific Sessions 2009.
In FOCUS (Transfusion Trigger Trial for Functional Outcomes in Cardiovascular Patients Undergoing Surgical Hip Fracture Repair), researchers evaluated two different RBC transfusion strategies for treating moderate postoperative anemia in older patients undergoing hip fracture repair. They looked at whether a more aggressive blood transfusion strategy could affect both functional recovery (primary endpoint: walking unassisted) and cardiovascular outcomes (secondary endpoint: a composite of in-hospital heart attack, unstable angina or death) in patients with cardiovascular disease (CVD) or cardiovascular risk factors who were having surgery to repair hip fracture.
Researchers are still analyzing functional results, but they found no evidence of a statistically significant benefit of the more aggressive treatment for CVD outcomes.
“Postoperative anemia is common after major surgery,” said Jeffrey L. Carson, M.D., the study’s principal investigator and Richard C. Reynolds Professor of Medicine and chief in the Division of General Internal Medicine at the University of Medicine and Dentistry of New Jersey’s Robert Wood Johnson Medical School in New Brunswick, N.J. “There is no doubt that blood transfusions are beneficial to patients who are severely anemic with hemoglobin levels below five to six grams per deciliter (g/dL). However, there are few studies and no large, randomized trials such as this one that investigate the effect of transfusions in asymptomatic patients with moderate anemia, between eight g/dL and 10 g/dL.”
A more aggressive transfusion strategy can be expensive and carry risks such as blood-borne infection, Carson said. So it’s important to know whether the treatment results in better outcomes.
The study followed 2,016 patients — ages 51 to 103, average age 81.6 — undergoing hip fracture repair surgery at 47 medical centers in the United States and Canada between August 2004 and February 2009. The elderly patients either had cardiovascular disease or were at high risk for it.
When the patients’ hemoglobin levels fell below 10 g/dL they were randomly assigned to either receive: blood transfusions to maintain their hemoglobin above 10 g/dL; or only receive transfusions if their hemoglobin fell below 8 g/dL or if they had symptoms of anemia such as chest pain believed to be of cardiac origin, low blood pressure, rapid heartbeat unresponsive to a fluid challenge (to rule out dehydration) or congestive heart failure.
“We found no statistically significant difference between groups, with 4.3 percent of the first group and 5.2 percent of the second group reaching the CVD endpoint during hospitalization,” Carson said. “A further secondary endpoint, the stand-alone rate of in-hospital mortality (2 percent for the first group vs. 1.4 percent for the second), also failed to reach statistical significance.
“Many clinicians base their decisions only on the hemoglobin levels. This trial seems to say that you need to look at every patient individually, to evaluate their symptoms. The overall interpretation of the trial will depend on consideration of functional outcomes, infection outcomes and longer-term mortality. Only after consideration of all these outcomes can the clinician fully weigh the pros and cons of the different transfusion methods”, Carson said.
The National Heart, Lung, and Blood Institute sponsored the study.
Co-authors are: Michael L Terrin, M.D.; Bernard Chaitman, M.D.; Jay Magaziner, Ph.D.; and David Sanders, M.D.
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