Major transfusions remain frequent despite the generalized use of tranexamic acid: an audit of 3322 patients undergoing cardiac surgery.

With the improvements made in non-invasive cardiac therapies (e.g. percutaneous transluminal coronary angioplasty) and the development of new drugs (e.g. antiplatelet agents), the characteristics of the patients undergoing cardiac surgery have significantly changed over the past decades. More and more, patients requiring cardiac surgery with cardiopulmonary bypass present with a large number of co-morbidities and treatments, which makes perioperative management even more challenging and places the patient at increased risk for perioperative bleeding and blood product transfusion. Multidisciplinary patient blood management programmes have been developed in order to improve perioperative management and to decrease the need for major blood product transfusions.

In this study, the authors aimed to determine the incidence and the predictors for major transfusions (defined as the transfusion of 4 units of red blood cells or more) in patients undergoing cardiac surgery. The primary objective was to determine whether the routine use of tranexamic acid may help reduce the incidence of major transfusion. Major transfusion was required in 23% patients, which can be considered as a high incidence. Age, low body mass index, low preoperative haemoglobin or platelet count, recent use of P2Y12 receptor blockers, chronic kidney disease, NYHA functional class, left ventricular ejection fraction of less than 30%, prior cardiac surgery, emergency, type of cardiac surgery, and duration of cardiopulmonary bypass were all predictors of major transfusion. The authors conclude that despite the routine use of tranexamic acid the incidence of major transfusion remains high, which underlines the need for safe and effective blood-sparing drugs.

While the study allows the identification of predictors of major transfusion, the absence of control group precludes any conclusion on the efficacy and safety of tranexamic acid in adults undergoing cardiac surgery. More importantly, this study highlights the complexity of major bleeding and its aetiology in cardiac surgical patients. This study confirms that even though tranexamic acid (or any other safe alternatives) should be part of our patient blood management protocols, massive bleeding during cardiac surgery is multifactorial and not ONLY explained by excessive fibrinolytic activation. Further studies are needed to develop multimodal approaches to reduce the incidence of major bleeding in cardiac surgery, taking into account that the routine use of tranexamic acid to inhibit fibrinolytic activation is not a magic bullet, and other options should be considered to manage other aspects of the coagulopathy (e.g. platelet dysfunction, hypofibrinogenaemia, or surgical aetiology).

– David Faraoni