Role of Tranexamic Acid for Reducing Blood Loss in Patients Undergoing Major Gastro-intestinal Surgery

Background:

Surgery is one of the major causes of blood loss. Though major blood loss is associated with cardiovascular procedures, liver transplantation etc, transfusions are frequently required in major gastrointestinal surgeries such as Whipples Procedure; Liver resections etc.1 Transfusion is associated with numerous risks such as mismatched transfusion, allergic reactions, transmission of infections, and acute lung injury etc.2 Though transfusion can be life saving, it is essential to rationalize transfusion whenever possible.

A number of agents have been tried in the past that stabilizes the coagulation system in the body minimizing blood loss; an ideal agent is yet to be found. Tranexamic acid, {trans-4-(aminomethyl) cyclohexanecarboxylic acid} is a competitive inhibitor of plasminogen activation, and at much higher concentrations, a noncompetitive inhibitor of plasmin.3 Tranexamic acid was first approved by the FDA in 1986 as an injection, under the brand name Cyklokapron®. This agent has been in use for last 40 years in many traumatic conditions with various successes with waxing and waning of its use. There has been a resurgence of interest in its use lately as more is known of this molecule. Tranexamic acid has been found to be very effective in orthopedic surgeries.4,5,6 A Cochrane review on 'antifibrinolytic use for minimizing perioperative blood transfusion' involving 21 trails of tranexamic acid vs. control in patients undergoing orthopedic surgery showed significant reduction in blood transfusion and perioperative blood loss.7 Randomized trial of tranexamic acid done on cardiac surgery patients as early as 1996 had shown significant reduction of red-cell transfusion and other blood products.8 CRASH 2 Trial (Clinical Randomization of an Antifibrinolytic in Significant Haemorrhage) is a large placebo-controlled trial studying the effects of early administration of a short course of tranexamic acid on death, vascular occlusive events and blood transfusion in adult trauma patients with significant hemorrhage. It involved 274 hospitals across 40 countries and started in 2005 and concluded that tranexamic acid could safely reduce the risk of death in bleeding trauma patients.9 Intraoperative use of low dose tranexamic acid has been observed to be safe and effective in reducing the rate of perioperative blood transfusions in patients undergoing radical retropubic prostatectomy.10 It has also been approved by FDA for use in menorrhagia.

Though it is being used in gastrointestinal bleeding and abdominal trauma, it is not routinely used in major gastrointestinal surgeries. In this context, this study is undertaken to evaluate the efficacy of tranexamic acid in major gastrointestinal surgeries.

Investigators hypothesize that addition of Tranexamic acid, an antifibrinolytic agent, to conventional therapy will lead to an improved outcome characterized by lower transfusion requirements.