Nationwide analysis of prehospital tranexamic acid for trauma demonstrates systematic bias in adherence to treatment guidelines: a retrospective cohort study

Background: Prehospital (PH) tranexamic acid (TXA) improves survival from trauma haemorrhage. Injury mechanism, physiology and sex demographics vary with patient age. We hypothesised that these factors influence TXA guideline compliance and examined national trends in PH use to identify any systematic biases in bleeding management.Materials methods: UK Trauma Audit & Research Network data for TXA eligible patients admitted to Major Trauma Centres were divided into cohorts: 2013-2015 (n=32,072) and 2017-2019 (n=14,974). Patients were stratified by PH, Emergency Department (ED) or no TXA use. Logistic regression models explored interaction between PH variables and TXA administration. Results are presented as Odds Ratios (OR) with 95% Confidence Intervals (CI).Results: PH TXA use increased from eight percent to 27% over time (P<0.001). Only three percent of eligible patients who fell <2 m received PH TXA vs. 63% with penetrating injuries (P<0.001). Older patients eligible for pre-hospital TXA were less likely to receive it compared to younger patients (>= 65 y old: 590 [13%] vs <65 y old: 3361 [33%], P<0.001). There was significant interaction between age and sex with fewer older women receiving PH TXA. In shocked patients, one third of females compared to a fifth of men did not receive TXA (P<0.001). There was a decrease in pre-hospital TXA use as age increased (P<0.001).Conclusions: Despite a three-fold increase in use, treatment guidance for PH TXA is not universally applied. Older people, women and patients with low energy injury mechanisms appear to be systematically under-treated. Training and education for pre-hospital providers should address these potential treatment biases.