Do heart surgery patients need so many blood transfusions?

Hospitals nationwide differ--sometimes greatly--over blood transfusions for heart surgery patients, despite evidence that those who undergo fewer transfusions recover just as well as those who receive more transfusions. Those findings, published today in two separate studies in the Journal of the American Medical Association, led a pair of doctors to conclude in an editorial also published in JAMA that hospitals should put more thought into their transfusion strategies. 

The first study, conducted by doctors in Brazil, determined that often, more transfusions aren't needed to ensure positive results. According to HealthDay News, researchers analyzed outcomes for 502 cardiac surgery patients who were split according to where their hemoglobin concentration levels stood. Some underwent transfusions when the concentration levels in their blood fell to 30 percent; for the others, doctors waited until their hemoglobin levels dropped to 24 percent. 

"[T]he use of a restrictive perioperative transfusion strategy compared with a more liberal strategy resulted in noninferior rates of the combined outcome of 30-day all-cause mortality and severe morbidity," the authors wrote. 

More than 100,000 patients at just under 800 hospitals were involved in the second study, which looked at patients undergoing a coronary bypass graft (CABG) surgery for the first time. Some hospitals transfused almost all such patients, while others transfused practically nobody. 

Drs. Aryeh Shander and Lawrence Goodnough--of Englewood (N.J.) Hospital and Medical Center and the Stanford University School of Medicine, respectively--called the second study's discrepancy disconcerting in light of the first study's results. 

"[D]espite magnitudes of differences between hospitals in terms of [red blood cell] transfusion rates, there were no significant differences in mortality rates between the hospitals," they wrote. "The absence of differences in mortality among centers with varying transfusion rates strongly suggests inappropriate transfusions." 

To learn more:
- here's the study on mortality rates
- and here's the study on varying transfusion rates
- check out this press release on the studies
- read the editorial in JAMA (reg. required)
- read the HealthDay News article