摘要Background:Antimicrobial de-escalation refers to starting the antimicrobial treatment with broad-spectrum antibiotics,followed by narrowing the drug spectrum according to culture results.The present study evaluated the effect of de-escalation on ventilator-associated pneumonia (VAP) in trauma patients.Methods:This retrospective study was conducted on trauma patients with VAP,who received de-escalation therapy (de-escalation group) or non-de-escalation therapy (non-de-escalation group).Propensity score matching method was used to balance the baseline characteristics between both groups.The 28-day mortality,length of hospitalization and Intensive Care Unit stay,and expense of antibiotics and hospitalization between both groups were compared.Multivariable analysis explored the factors that influenced the 28-day mortality and implementation of de-escalation.Results:Among the 156 patients,62 patients received de-escalation therapy and 94 patients received non-de-escalation therapy.No significant difference was observed in 28-day mortality between both groups (28.6％ vs.23.8％,P =0.620).The duration of antibiotics treatment in the de-escalation group was shorter than that in the non-de-escalation group (11 [8-13] vs.14 [8-19] days,P =0.045).The expenses of antibiotics and hospitalization in de-escalation group were significantly lower than that in the non-de-escalation group (6430 ± 2730 vs.7618 ± 2568 RMB Yuan,P =0.043 and 19,173 ± 16,861 vs.24,184 ± 12,039 RMB Yuan,P =0.024,respectively).Multivariate analysis showed that high Acute Physiology and Chronic Health Evaluation Ⅱ (APACHE Ⅱ) score,high injury severity score,multi-drug resistant (MDR) infection,and inappropriate initial antibiotics were associated with patients' 28-day mortality,while high APACHE Ⅱ score,MDR infection and inappropriate initial antibiotics were independent factors that prevented the implementation of de-escalation.Conclusions:De-escalation strategy in the treatment of trauma patients with VAP could reduce the duration of antibiotics treatments and expense of hospitalization,without increasing the 28-day mortality and MDR infection.