Pharmacological approaches to reducing blood loss and transfusions in the surgical patient

Abstract

Purpose: To review the efficacy, effectiveness and safety of hemostatic drugs to reduce surgical blood loss. Methods: Analysis of randomized controlled trials and meta-analyses exploring the efficacy of desmopressin, aprotinin, lysine analogues and recombinant activated factor VII (rFVIIa) on clinically important endpoints. Main findings: Although potentially useful in surgical patients with mild hemophilia or type I von Willebrand's disease, desmopressin has no proven benefit in patients without previous hemostatic defects. Aprotinin has been studied extensively in cardiopulmonary bypass surgery, with evidence of a blood sparing effect. Additional benefits are suggested. The drug is less consistently effective in liver transplantation and major orthopedic surgery. Although rare, hypersensitivity reactions to aprotinin may occur, especially on re-exposure. Tranexamic acid can reduce blood transfusion in cardiac surgery, liver transplantation and total knee arthroplasty surgery with a satisfactory safety profile. Epsilon aminocaproic acid has not been investigated adequately, despite its widespread use. While rFVIIa may be beneficial in controlling massive coagulopathic bleeding in trauma and surgical patients, there is currently no evidence to support its prophylactic use in elective surgical patients. Conclusion: Aprotinin and tranexamic acid are valuable pharmacologic options for reducing surgical bleeding. The expected benefit of these drugs is highly dependent on the actual blood usage for a given procedure at the institutional level. More studies using clinically significant endpoints are necessary to assess the relative efficacy and optimal dosing of these drugs.