27 Ago Influence of empirical double-active combination antimicrobial therapy compared to active monotherapy on mortality in patients with septic shock: a propensity score-adjusted and matched analysis.

Objectives
To evaluate the influence on mortality of empirical double-active combination antimicrobial therapy (DACT) compared with active monotherapy (AM) in septic shock patients.
Materials and Methods
Retrospective study of monomicrobial septic shock patients admitted from 2010 to 2015 to a university centre. A propensity score (PS) was calculated by logistic regression model taking the assigned therapy as dependent variable and used as a covariate in multivariate analysis predicting mortality and for matching patients who received DACT or AM. Multivariate models comprising the assigned therapy group and the PS were built for specific patient subgroups.
Results
Five-hundred and seventy-six patients were included (340 received AM and 236 DACT). No difference in 7-, 15- and 30-day all-cause mortality was found between groups either in the PS-adjusted analysis or in the PS-matched cohorts. In patients with neutropenia, DACT was independently associated with a better outcome at 15 (OR 0.29, 95%CI 0.09-0.92) and 30 (OR 0.25, 95%CI 0.08-0.79) days, while in patients with Pseudomonas aeruginosa infection, DACT was associated with lower 7- (OR 0.12, 95%CI 0.02-0.7) and 30-day (OR 0.26, 95%CI 0.08-0.92) mortality.
Conclusions
All-cause mortality was similar in patients with monomicrobial septic shock receiving DACT and AM. However, a beneficial influence of DACT on mortality in patients with neutropenia and those with Pseudomonas aeruginosa infection aeruginosa is worthy of further study.