The effectiveness of prophylactic antibiotics administration on the prevention of ventilator-associated pneumonia in out-of-hospital cardiac arrest patients undergoing ECPR.

Aim: Despite improved outcomes with extracorporeal cardiopulmonary resuscitation (ECPR) in out-of-hospital cardiac arrest (OHCA) patients, ventilator-associated pneumonia (VAP) remains a significant complication. While prophylactic antibiotics are not recommended for conventional CPR, their effectiveness in ECPR patients remains unclear. Methods: This was a secondary analysis of the SAVE-J II study, a multicenter, retrospective cohort of OHCA patients treated with ECPR. Patients who died within three days of admission were excluded. The primary outcome was early-onset VAP development, with secondary outcomes being 30-day mortality and neurological outcomes at discharge. The effect of prophylactic antibiotics, administered within 24 h after admission, was estimated by combining propensity score matching and multivariable logistic regression. Missing covariates were multiply imputed. Results: Of 2157 patients, 919 were included for propensity score matching, yielding a matched cohort of 448. In the matched cohort, prophylactic antibiotics administration was not significantly associated with VAP incidence (aOR, 0.62; 95% CI, 0.39-1.01), although the incidence was numerically lower (24.1% vs 31.3%). No effects were observed in 30-day mortality (aOR, 1.00; 95% CI, 0.64-1.57) or unfavorable neurological outcomes (aOR, 0.92; 95% CI, 0.56-1.52). Sensitivity analyses using different definitions of VAP and population yielded consistent results. Conclusions: Although point estimates suggested a possible reduction in VAP, the results did not reach statistical significance, and no improvements in survival or neurological outcomes were detected. Further randomized controlled trials are warranted before advocating routine prophylactic antibiotic use.