the Use of Tranexamic Acid to Prevent the Bleeding in Bariatric Surgery

Participants were randomized in a 1:1 ratio to receive tranexamic acid or placebo using a computer-generated block randomization sequence (block size = 4) prepared by an independent pharmacist. Allocation concealment was maintained with sequentially numbered, opaque, sealed envelopes. The pharmacist also prepared indistinguishable infusion bags containing either tranexamic acid (1 g diluted in 100 mL of 0.9% saline) or placebo (100 mL of 0.9% saline). The infusion was administered intravenously over 10-15 minutes immediately after induction of anesthesia and before skin incision, at a maximum rate of 100 mg per minute. Blinding was maintained for patients, anesthesiologists, scrub nurses, and all postoperative assessors, while the operating surgeon was necessarily unblinded, becoming aware of allocation only once the envelope was opened in the operating room. All analyses were performed according to the intention-to-treat principle.