Karkouti et al. performed a pragmatic multicentre stepped-wedge cluster randomised controlled trial assessing the effectiveness of implementing a point-of-care (POC) haemostatic testing-based transfusion algorithm to reduce the need for allogeneic blood products and the incidence of massive bleeding in patients undergoing cardiac surgery with cardiopulmonary bypass at 12 Canadian hospitals from Oct 6, 2014 to May 1, 2015. The authors collected data from 7402 patients, of whom 3555 underwent cardiac surgery during the control phase and 3847 during the intervention phase.

Implementation of a transfusion algorithm based on POC haemostatic testing was found to significantly reduce the incidence of red blood cell and platelet transfusion as well as the incidence of massive bleeding. However, no effect was observed with regard to transfusion of other blood products, postoperative complications and mortality.

This study represents a major piece in the understanding of how the implementation of POC monitoring-guided transfusion algorithms can influence blood product transfusions, outcomes and resource utilisation. As already reported in smaller studies, the implementation of an algorithm-based transfusion strategy helps reduce the incidence of massive bleeding and decrease the incidence of blood product transfusion, without major improvements in outcomes and mortality.

Are these results surprising? Not really. It seems reasonable that the adoption of a transfusion algorithm based on standardised criteria helps improve bleeding management and leads to a more rational transfusion strategy. The following questions may be raised: How good was the transfusion policy before the implementation of the standardised approach? Does POC coagulation monitoring really make a difference, or would the adoption of a standardised algorithm without POC testing lead to the same results?

Last but not least, the study also confirmed that mortality post cardiac surgery is complex and multifactorial. While overtransfusion should be avoided for multiple reasons (e.g. transfusion-related complications and costs), decreasing transfusion and bleeding alone can hardly translate into better outcomes.

In conclusion, the implementation of a standardised transfusion algorithm helps reduce the need for allogeneic blood products and the incidence of massive postoperative bleeding. While this might impact resource utilisation, it does not translate into improved clinical outcomes.

– Dave Faraoni