The Use of Antifibrinolytic Agents in Spine Surgery

Abstract

Antifibrinolytic agents have been shown to decrease the blood loss associated with major orthopaedic surgical procedures. Spine surgery, particularly procedures performed for deformity correction and procedures involving long arthrodesis constructs, can be associated with a large amount of blood loss requiring blood transfusions. The purpose of the present study was to determine if antifibrinolytic agents reduced blood transfusions in patients managed with spine surgery and to see if one agent had a greater effect than another. A systematic review and meta-analysis of the available literature were performed to investigate the efficacy of aprotinin, tranexamic acid, and epsilon-aminocaproic acid in terms of reducing blood loss and blood transfusions in patients undergoing spine surgery. This meta-analysis was focused on the role of these agents in major spine operations as reported in eighteen clinical trials that included information on the drug dosage, the age of the patient, blood loss, blood transfusions, surgery complexity, and complications. Compared with control groups, the treatment groups for all three antifibrinolytic agents maintained lower levels of total blood loss and transfusions associated with spine surgery. The effect size (d) of the differences in total blood loss between the treatment and control groups ranged from -0.668 (95% confidence interval, -0.971 to -0.365) to -0.936 (95% confidence interval, -1.240 to -0.632) across all three agents. The effect size (d) of the differences in total blood transfusions between the treatment and control groups ranged from -0.466 (95% confidence interval, -0.764 to -0.167) to -0.749 (95% confidence interval, -1.046 to -0.453) across all three agents. Aprotinin, tranexamic acid, and epsilon-aminocaproic acid are effective for reducing blood loss and transfusions in patients managed with spine surgery. With the exception of aprotinin, the side-effect profiles of these agents have not been shown to cause any substantial morbidity or to increase the rate of thromboembolic events. Epsilon-aminocaproic acid had a greater effect on reducing blood transfusions as the complexity of surgery increased. The surgeon and/or the anesthesiologist should consider the use of antifibrinolytic agents for patients undergoing spinal procedures in which a large amount of blood loss can be expected; however, at the present time, this is not a United States Food and Drug Administration-approved indication for these agents.