Use of blood products and risk of stroke after coronary artery bypass surgery

Background. The impact of blood transfusion on the development of post-operative stroke after coronary artery bypass grafting (CABG) is not well established. We, therefore, investigated this issue. Materials and methods. Complete data on peri-operative blood transfusion were available for 2,226 patients who underwent CABG in three Finnish hospitals. Results. Stroke occurred post-operatively in 53 patients (2.4%). Logistic regression showed that pre-operative creatinine (OR 1.003, 95% CI 1.000-1.006), extracardiac arteriopathy (OR 2.344, 95% CI 1.133-4.847), pre-operative atrial fibrillation (OR 2.409, 95% CI 1.149-5.052), and the number of packed red blood cell units transfused (OR 1.121, 95% CI 1.065-1.180) were significantly associated with post-operative stroke. When the various blood product transfusions instead of transfused units were included in the multivariable analysis, solvent/ detergent treated plasma (Octaplas ® ) transfusion (OR 2.149, 95% CI 1.141-4.047), but not red blood cell transfusion, was significantly associated with postoperative stroke. Use of blood products ranging from no transfusion (stroke rate 1.6%) to combined transfusion of red blood cells, platelets and Octaplas ® was associated with a significant increase in post-operative stroke incidence (6.6%, adjusted analysis: OR 1.727, 95% 1.350-2.209). Patients who received >2 units of red blood cells, >4 units of Octaplas ® units and >8 units of platelets had the highest stroke rate of 21%. CART analysis showed that increasing amount of transfused Octaplas ® , platelets and history of extracardiac arteriopathy were significantly associated with post-operative stroke. Conclusions. Transfusion of blood products after CABG has a strong, dose-dependent association with the risk of stroke. The use of Octaplas ® and platelet transfusions seem to have an even larger impact on the development of stroke than red blood cell transfusions.