BACKGROUND : Trauma is a leading cause of death in young people and hemorrhagic shock is the second responsible of the mortality rates. Hypoperfusion is hard to diagnose clinically and might stay patent especially in patients whose response mechanisms are e!cient. In this context, arterial Base Excess (BE) has been proposed to be used as an early indicator of hypoperfusion. The aim of this study was to evaluate the prognostic value of admission BE in severe trauma patients admitted to the Emergency resuscitation room.

METHODS : It was a prospective prognostic study. We included severe trauma patients with high velocity criteria and admitted to the resuscitation room (33 months period). Arterial blood gas sample was withdrawn and BE calculated. Multivariate analysis was performed to identify the early predictive factors of mortality and at Day-7 after trauma. Moreover, ROC characteristics and survival curves were underwent.

RESULTS : We included 479 patients. Median age was 37 (18-90) with sex-ratio=4.2. Road tra!c accident was the most frequent cause n (%):358(75) Clinical characteristics were n(%): GCS<13: 170(35); SBP<90 mmHg: 64(13) and SpO2 <90%: 82(17). Mean ISS was 22 ± 13. Rates of mortality were respectively at day 1 and day 7: 2,2% and 27,3%. Median BE was -3,2 mmol/l (-25; 28). Forty-$ve per cent had a BE ≤ -3,5 mmol/l. In multivariate analysis with logistic regression, initial BE ≤ -6,5 mmol/L was an independent predictive factor of $rst day mortality with an adjusted Odds Ratio; [CI95%] = 3,17; [1,4-7,1]; p=0,005. Similar results were found while studying 7 days mortality with an adjusted Odds Ratio; [CI95%] = 1,5; [1,14-1,96]; p=0,003. BE showed high prognostic value for both mortality rates. Survival curve was significant for BE> -6,5mmol/l. 

CONCLUSION : In this study, BE showed a signi$cant prognostic value towards immediate and early mortality and could be proposed as a marker of detecting severity in trauma patients admitted to the emergency ward. 

Key-words: Base Excess , polytrauma, mortality, emergency resuscitation room, prognosis.