WEDNESDAY, Nov. 15, 2006 (HealthDay News) -- Blood transfusions can benefit some patients with acute coronary syndrome but will harm others and should be used in moderation, U.S. researchers report.
Acute coronary syndrome (ACS) is a condition in which patients show signs of a heart attack.
The findings support previous research that suggests that doctors should reconsider how they make decisions about which ACS patients should get transfusions, said lead investigator Dr. Karen Alexander of Duke University in Durham, N.C.
For this study, involving more than 44,000 patients, Alexander's team focused on a key blood measure (hematocrit) to see when doctors made the decision to give a patient a transfusion. They then compared this transfusion "decision point" to patient outcomes.
Hematocrit represents the percentage of oxygen-carrying red blood cells in blood. Normal hematocrit is 42 percent to 52 percent in men and 36 percent to 48 percent for women.
This study found that transfusions were most beneficial in patients whose lowest recorded hematrocrit level was less than 24 percent, but were associated with harm in patients whose lowest recorded hematocrit levels were higher than 30 percent. In patients with hematocrit levels that bottomed out at between 24 percent and 30 percent, transfusions caused no harm or benefit, the researchers said.
"Providers may want to reconsider how they decide which patients should get transfusions," Alexander said. "Our data confirms no harm or benefit in the medium range of 24 percent to 30 percent, so in this group of patients, it might be best to wait and see if the hematocrit drops farther before making the decision to transfuse. Given the scarcity of the blood supply, we certainly want to apply this therapy to those who stand to benefit the most while at the same time avoiding harm."
The study was to be presented Wednesday at the American Heart Association's annual meeting in Chicago.
The American Heart Association has more about acute coronary syndrome.