A new study has found that blood transfusions lead to more surgery complications in women than men.
Researchers from from the University of Rochester Medical Center and University of Michigan Health System, showed that after a heart surgery, women die and get infections more often than men, because they are susceptible to receiving more blood transfusions, which in turn boost the risks of bad outcomes.
They said the study also raises concerns about transfusions, an ancient medical practice that some doctors now believe is overused.
Blood transfusions were once reserved for only the sickest patients, but have evolved from a life-saving therapy to an elective treatment for many illnesses. Patients today receive donor blood, for example, to prevent severe anemia and improve oxygen delivery due to heart failure.
"For 100 years we've assumed blood transfusions are good for people, but most of these clinical practices grew before we had the research to support it," said co-author Neil Blumberg, M.D., professor of Pathology and Laboratory Medicine and director of Transfusion Medicine at the University of Rochester Medical Center.
In the current study, Blumberg and corresponding author Mary Rogers, Ph.D., of the University of Michigan, Department of Internal Medicine, analyzed the data of 380 adult Rochester, N.Y., patients who had primary coronary artery bypass graft surgery, primary valve replacement, or both, in 1997 or 1998 at Strong Memorial Hospital.
Researchers looked at in-hospital deaths, lengths of stay, number of days of infection and fever, and whether any patients developed pulmonary dysfunction, a serious side effect of heart surgery.
Sixty percent of the patients were men and about 40 percent were women. However, the women were 44.6 percent more likely to receive a blood transfusion than the men.
Of the 150 women studied, 149 (99 percent) received donor blood during their hospitalisation, compared to 77 percent of the men.
The study showed that when men and women had equivalent, normal preoperative red blood counts, 99 percent of the women still received transfusions, compared to 62 percent of the men. This suggests a reliance on the red cell concentration as the prime factor in determining when a transfusion is given, the authors said.
Although a direct connection between blood transfusions and infections is being debated among scientists, several studies support the notion that donor blood can provoke a negative response from the patient's immune system.
Of the 380 patients, 13 died while in the hospital; all of the 13 patients received blood transfusions, and infection was strongly related to death. Blood transfusions correlated with more days of fever, more days in intensive care, and a longer hospital stay, particularly if the patient got more than four units of blood.
Women were more likely to die in the hospital (6.7 percent) than men (1.3 percent), and 11 percent of the women in the study developed pulmonary dysfunction after surgery, compared with 3.9 percent of the men.
The study is published in the December Journal of Women's Health.