Transfusion rates vary significantly amongst Canadian medical centres

To document variation of transfusion practice following repair of hip fracture or cardiac surgery, as well as those requiring intensive care following a surgical intervention or multiple trauma (high risk patients).

We documented rates of allogeneic red cell transfusion in 41,568 patients admitted to 11 hospitals across Canada between August 1998 and August 2000 as part of a retrospective observational cohort study. In the subgroup of 7,552 patients receiving red cells, we also compared mean nadir hemoglobin concentrations from centre to centre.

The overall rate of red cell transfusion was 38.7%, and ranged from 23.8% to 51.9% across centres among the 41,568 perioperative and critically ill patients. Women were more likely to be transfused (43.7% vs 35.3%, P < 0.0001), with higher rates of transfusion in eight of 11 centres. Compared to a chosen reference hospital having a crude transfusion rate near the median, the adjusted odds of transfusion ranged from 0.44 to 1.53 overall, from 0.42 to 1.22 in patients undergoing a hip fracture repair, from 0.72 to 3.17 in cardiac surgical patients undergoing cardiac surgery, and from 0.27 to 1.11 in critically ill and trauma patients. In the 7,552 transfused patients, the mean adjusted nadir hemoglobin was 74.0 +/- 4.83 g x L(-1) overall, and ranged from 66.9 +/- 1.7 g x L(-1) to 84.5 +/- 1.6 g x L(-1) across centres. Similar differences among centres were observed amongst hip fracture patients (71.2 +/- 2.9 g x L(-1) to 82.8 +/- 1.7 g x L(-1)), cardiac surgical patients (65.7 +/- 1.1 g x L(-1) to 77.3 +/- 1.0 g x L(-1)) and critically ill and trauma patients (66.1 +/- 3.04 g x L(-1) to 87.5 +/- 2.5 g x L(-1)).

We noted significant differences in the rates of red cell transfusion and nadir hemoglobin concentrations in various surgical and critical care settings.