Objective: To evaluate the effect of locally applied tranexamic acid on postoperative blood loss and measures of fibrinolysis in drained blood.
Design: Prospective study.
Setting: University hospital, Norway.
Patients: 30 patients operated on for low back pain by screw fixation of the lumbar spine, 16 of who were randomised to be given topical tranexamic acid.
Main outcome measures: Postoperative blood loss after 18 hours. Concentrations of plasmin/alpha2-antiplasmin (PAP) and D-dimer in arterial and drained blood at the time of wound closure and in drained blood after 1 hour.
Results: In the tranexamic group median (interquartile) blood loss was reduced by half from 525 (325-750) ml to 252 (127-465) ml, p = 0.02. In drained blood after one hour the increase in the concentration of PAP was 150 (109-170)% and D-dimer 150 (107-272)% in the tranexamic group compared with the control group where the increase in PAP was 320 (140-540)% and D-dimer 260 (161-670)%.
Conclusion: Tranexamic acid applied in the wound inhibits blood loss by up to a half in major orthopaedic surgery probably because it prevents excessive fibrinolysis.