Context.— The risks of blood transfusion have been studied extensively but the
benefits and the hemoglobin concentration at which patients should receive
a transfusion have not.
Objective.— To determine the effect of perioperative transfusion on 30- and 90-day
Design.— Retrospective cohort study.
Setting.— A total of 20 US hospitals between 1983 and 1993.
Participants.— A total of 8787 consecutive hip fracture patients, aged 60 years or
older, who underwent surgical repair.
Main Outcome Measures.— Primary outcome was 30-day postoperative mortality; secondary outcome
was 90-day postoperative mortality. The "trigger" hemoglobin level was defined
as the lowest hemoglobin level prior to the first transfusion during the time
period or, for patients in the nontranfused group, as the lowest hemoglobin
level during the time period.
Results.— Overall 30-day mortality was 4.6% (n=402; 95% confidence interval [CI],
4.1%-5.0%); overall 90-day mortality was 9.0% (n=788; 95% CI, 8.4%-9.6%).
A total of 42% of patients (n=3699) received a postoperative transfusion.
Among patients with trigger hemoglobin levels between 80 and 100 g/L (8.0
and 10.0 g/dL), 55.6% received a transfusion, while 90.5% of patients with
hemoglobin levels less than 80 g/L (8.0 g/dL) received postoperative transfusions.
Postoperative transfusion did not influence 30- or 90-day mortality after
adjusting for trigger hemoglobin level, cardiovascular disease, and other
risk factors for death: for 30-day mortality, the adjusted odds ratio (OR)
was 0.96 (95% CI, 0.74-1.26); for 90-day mortality, the adjusted hazard ratio
was 1.08 (95% CI, 0.90-1.29). Similarly, 30-day mortality after surgery did
not differ between those who received a preoperative transfusion and those
who did not (adjusted OR, 1.23; 95% CI, 0.81-1.89).
Conclusions.— Perioperative transfusion in patients with hemoglobin levels 80 g/L
(8.0 g/dL) or higher did not appear to influence the risk of 30- or 90-day
mortality in this elderly population. At hemoglobin concentrations of less
than 80 g/L (8.0 g/dL), 90.5% of patients received a transfusion, precluding
further analysis of the association of transfusion and mortality.