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Prehospital administration of tranexamic acid in trauma patients: A 1:1 matched comparative study from a level 1
Ayman El-Menyar1, Brijesh Sathian2, Bianca M Wahlen3
1Department of Surgery, Clinical Research, Trauma & Vascular Surgery, Hamad General Hospital (HGH), Doha, Qatar; Clinical Medicine, Weill Cornell Medical College, Doha, Qatar.
Purpose:
The purpose of this study was to test the efficacy of prehospital administration of tranexamic acid (TXA) to injured patients on mortality, thromboembolic events and need for blood transfusion in a level 1 trauma center.
Methods:
We conducted a retrospective study comparing adult trauma patients receiving or not receiving prehospital TXA between January 2017 and September 2018. Patients not receiving TXA but transfused within 4 h of admission were 1:1 matched to TXA-treated patients for age, sex, injury severity score, head abbreviated injury score, prehospital heart rate and systolic blood pressure.
Results:
In total 204 patients were included (102 TXA and 102 control), with a mean age of 31 years. On admission, shock index (p = 0.03) and serum lactate (p = 0.001) were greater in the control group, whereas the initial base deficit, hemoglobin levels and EMS time were comparable in both groups. The odd ratio (OR) for shock index ≥0.9 after TXA administration was 0.44 (95% CI 0.23-0.84). The median amount of blood transfusion was greater in the control group [eight units (range 1-40) vs three (range 0-40), p = 0.01] as well as the use of massive blood transfusion [OR 0.35 (95% CI 0.19-0.67)]. In the TXA group, VTE was higher [OR 2.0 (95% CI 0.37-11.40)]; whereas the overall mortality was lower [OR 0.78 (95% CI 0.42-1.45)] without reaching statistical significance.
Conclusions:
Prehospital TXA administration is associated with less in-hospital blood transfusion and massive transfusion protocol (MTP). There is no significant increase in the thromboembolic events and mortality, however, further evaluation in larger clinical trials is needed.
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