Blood Transfusions During Surgery Found Risky

Blood transfusions during surgery may triple the risk of suffering a heart attack or stroke, according to a new study.

Researchers from the Bristol Heart Institute at Bristol University (United Kingdom) examined the association between red blood cell transfusion and adverse outcomes in 8,500 cardiac surgery patients between April 1, 1996, and December 31, 2003. Clinical, hematology, and blood transfusion databases were linked with the United Kingdom (UK) population register; additional hematocrit information was obtained from intensive care unit charts. Composite infection (respiratory or wound infection or septicemia) and ischemic outcomes (myocardial infarction, stroke, renal impairment, or failure) were pre-specified as coprimary end points. Secondary outcomes were resource use, cost, and survival.

The researchers found that patients who received a red blood cell transfusion during surgery experienced a three-fold increase in complications arising from lack of oxygen to key organs, such as in a heart attack or stroke. The risks associated with transfusion occurred regardless of hemoglobin levels, age, or health of the patient. This is a finding at odds with the widely held belief that red cell transfusion improves delivery of oxygen to tissues. The researchers also found that at any time after their operations, transfused patients were less likely to have been discharged from hospital, and were more likely to have died. The study was published in the November 27, 2007, issue of Circulation, the journal of the American Heart Association (AHA).

"This study demonstrates the cost implications of our current transfusion practice,” said lead author Gavin Murphy, M.D., Ph.D. "This is important, particularly in modern health systems where resources are finite, and should encourage the sort of research that will address the major health issues raised in the study.”

"This study shows the importance of putting such widespread beliefs to the test since it suggests that such transfusions may cause more problems than they solve,” said Professor Peter Weissberg, medical director of the British Heart Foundation (BHF, London, UK). "The results are a step towards making heart surgery even safer by flagging up an issue we can now address through research and improved transfusion guidelines.”


Related Links:
Bristol University
British Heart Foundation