A study spanning 40 countries suggests that thousands of trauma patients could be saved from bleeding to death if they received an injection of the compound tranexamic acid (TXA).

TXA aids clotting by preventing clots that have formed from dissolving. It has been known for some time that bleeding problems during surgery are often due not to the inability of blood clots to form but to their inability to persist; they form but are then broken down, and bleeding continues. Studies have shown that TXA and similar compounds help prevent this during surgery and can reduce the need for blood transfusions. This led to the idea that TXA might have similar effects in trauma patients, which was how the CRASH-2 trial came to be.

Any procedure that increases clotting carries the worry that it may also be increasing events such as heart attacks, strokes and blood clots in the lung. This study found no such harmful effect from TXA.

CRASH-2 tested the effect of randomized TXA injection in over 20,000 adult trauma patients in 274 hospitals in 40 countries. Patients were selected for the trial only when doctors were "substantially uncertain" whether or not to treat with TXA. That is, all patients whom the doctors felt clearly needed TXA received it and were not part of the trial. When there was uncertainty, consenting patients being treated within eight hours of their injury were eligible for the trial. Trial patients randomly received an injection of either one gram TXA or placebo, followed by an intravenous infusion of one more gram delivered gradually over eight hours. Patients were then tracked for 28 days.

The compound isn't a magic bullet; the study suggests that injections of TXA lead to 10% fewer deaths overall and 15% fewer deaths from bleeding. With about 600,000 trauma patients bleeding to death yearly from car accidents, gunshot wounds and other injuries, this could mean 60,000-90,000 lives saved worldwide. Injury is the second leading cause of death in people aged 5-45.

Any procedure that increases clotting carries the worry that it may also be increasing events such as heart attacks, strokes and blood clots in the lung. This study found no such harmful effect from TXA

TXA is not an exotic, expensive medication. It costs about $4.50 per gram, meaning that the dose used in the study cost $9 per patient. So cost isn't a barrier to TXA becoming a standard treatment for trauma patients.

An article on the CRASH-2 trial was published online by The Lancet on June 15.