Elderly hip surgery patients with cardiovascular disease do equally well whether they receive transfusions to maintain a hemoglobin level of 8 g/dL or more than 10 g/dL, a randomized trial has found.
Neither the restrictive nor the liberal transfusion protocol significantly altered the primary outcomes of mortality or functional status, or any of the prespecified secondary outcomes, Dr. Jeffrey L. Carson and his colleagues wrote in the Dec. 14 issue of the New England Journal of Medicine.
"Our findings suggest that it is reasonable to withhold transfusion in patients who have undergone surgery in the absence of symptoms of anemia or a decline in the hemoglobin level below 8 g/dL, even in elderly patients with underlying cardiovascular disease or risk factors," Dr. Carson, of the University of Medicine and Dentistry of New Jersey, Piscataway, and his coauthors wrote (N. Engl. J. Med. 2011 Dec. 14 [doi:10.1056/NEJMoa1012452]).
The investigators randomized 2,016 patients undergoing hip fracture surgery to either a liberal or restrictive transfusion protocol. The liberal protocol called for 1 unit of packed red cells and additional blood to maintain a hemoglobin level of more than 10 g/dL, whereas the restrictive one called for transfusions at the physician’s discretion or when hemoglobin levels fell to below 8 g/dL.
The study’s primary end points were death or an inability to walk 10 feet without assistance by 60 days after surgery. The secondary outcomes were in-hospital heart attack, unstable angina, or death for any reason.
The patients’ mean age was 82 years; 63% had cardiovascular disease. Women made up 75.2% of the liberal strategy group and 76.3% of the restrictive group. Postoperative hemoglobin before transfusion was 1.3 g/dL higher in the liberal protocol group than in the restrictive group – a significant difference.
Those in the liberal group also received significantly more blood than did those in the restrictive group (median 2 vs. 0 units). A total of 59% of patients in the restrictive group did not receive any blood, compared with only 3% in the liberal group.
Despite the differences in transfusion volume, the study found no significant differences in any primary or secondary outcomes. The 60-day rate of mortality or the inability to walk 10 feet unassisted was 35% in each group. At 60 days, 8% of the liberal protocol group and 7% of the restrictive group had died, a nonsignificant 1% absolute risk reduction.
Nor were the combined secondary end points significantly different. In-hospital heart attack, unstable angina, or death within 30 days occurred in 4% of the restrictive group and in 5% of the liberal group. There were no significant differences in adverse events or length of hospital stay.
Men in the liberal protocol group were significantly more likely than women to achieve the primary end point (odds ratio, 1.45 vs. 0.74). The investigators said this was an unexpected finding that could have been due to chance. Interactions based on age, race, or cardiovascular disease were not significant.
FOCUS (Transfusion Trigger Trial for Functional Outcomes in Cardiovascular Patients Undergoing Surgical Hip Fracture Repair) was sponsored by the National Institutes of Health. Dr. Carson reported that he had received NIH funding for the study. Two other authors reported multiple financial relationships with pharmaceutical and medical device companies.