Ultra-Low Dose Aprotinin Effects on Reducing the Need for Blood Transfusion in Cardiac Surgery: A Double Blind Randomized Clinical Trial

Objective- The recommended dose of aprotinin [3-6 million kallikrein inhibitor units (KIU)] reduces the rate of bleeding after open heart surgery and the need for the transfusion of blood products. However, issues have been raised due to the cost and some side effects of aprotinin, and the use of low doses has been noticed. Various studies have demonstrated the effectiveness of two million KIU doses, whereas there is controversy over one million KIU doses. The purpose of this study was to assess the effect of one million KIU aprotinin on bleeding and the need for transfusion after cardiac surgery. Methods- A double-blind randomized clinical trial was conducted on 162 coronary artery bypass grafting (CABG) and valve surgery patients from April 2004 to December 2005. The patients were randomly divided into two groups of 81 individuals. In the aprotinin group, 0.5 million KIU aprotinin was infused before and again during cardiopulmonary bypass (CPB); and in the placebo group, 100 ml normal saline (NS) was infused before and during CPB. The need for the use of fresh frozen plasma (FFP) and packed red blood cells (pRBCs) transfusion during and after surgery and the amount of chest tube drainage at 6,12 and 24 hours after surgery were measured in the two groups. Results- The mediastinal and pleural drainage at 6 hours after surgery was 190پ}24 ml in the aprotinin group and 266پ}33 ml in the placebo group (p=0.066). The amount of bleeding at 12 and 24 hours was significantly different between the two groups (p=0.048 and p=0.009, respectively). The frequency of blood product transfusion in the aprotinin group was 68% and in the placebo group was 75% (p=0.02). The number of pRBCs and FFP units transfused was significantly lower in the aprotinin group (p=0.000) and p=0.005, respectively). The total amount of blood and products transfusion in the aprotinin group was 2.56 پ} 0.27 units and in the placebo group it was 4.37پ} 0.27 units (p=0.0001). Conclusion- The results indicate that the use of one million KIU of aprotinin (ultra-low dose) in adult cardiac surgery is effective in reducing postoperative bleeding and transfusion requirements (Iranian Heart Journal 2007; 8 (4): 11-16).