Speed is all important when it comes to administering the clot-stabilising drug tranexamic acid to patients with serious injury or women with severe bleeding after childbirth, note UK researchers.
Their study found that the likelihood of death due to blood loss was reduced by over 70% if the low-cost, readily-available drug was given immediately after injury or birth.
“Responding quickly can be the difference between life and death”
But the chances of survival fell by 10% for each 15 minute delay, with no benefit seen after three hours, according to a meta-analysis of over 40,000 patients, published in The Lancet.
Antifibrinolytic drugs – such as tranexamic acid, aminocaproic acid, and aprotinin – been used for years to reduce heavy menstrual bleeding and to cut the need for blood transfusions during surgery.
The new study is based on the WOMAN and CRASH-2 trials, which previously showed tranexamic acid cut deaths due to post-partum haemorrhage and after serious injury by about a third if given within three hours of bleeding onset.
For the new analysis, the researchers looked at data from the two trials and found that almost two-thirds of bleeding deaths occurred within 12 hours of onset and those due to post-partum haemorrhage peaked two to three hours after childbirth.
“Most haemorrhage deaths occur within hours of bleeding onset”
Overall, survival from severe bleeding was increased by a fifth with the use of tranexamic acid compared to placebo, irrespective of the site of bleeding.
For example, 1.5% of women given tranexamic acid died of bleeding versus 1.9% of women given placebo plus standard care, and 4.9% trauma patients given tranexamic acid died of bleeding versus 5.7% given placebo and standard care.
This figure rose to 70% if the drug was administered immediately. For every 15 minute delay in treatment, survival benefit was cut by about 10%, even after taking into account age and systolic blood pressure. No benefit was seen if treatment was delayed beyond three hours.
The researchers also found no evidence of complications or increased risk of clotting compared to placebo, and fewer cases of heart attacks were noted with tranexamic acid.
Immediate treatment with antifibrinolytics ‘could save lives’
Study author Professor Ian Roberts, from the London School of Hygiene and Tropical Medicine, said: “Responding quickly can be the difference between life and death.
“We have to make sure tranexamic acid is available before patients reach hospital and whenever a woman gives birth,” he said.
Professor Roberts also noted that tranexamic acid was “safe, cheap, easily administered, and does not need to be refrigerated”.
He added that, given the importance of early treatment, time from bleeding onset to early treatment should be “audited and communicated to healthcare professionals”.
“Establishing national or regional quality improvement initiatives, with best practice benchmarking of time to treatment, might improve survival,” he said.