Prior carbapenem exposure increases the incidence of ventilator-associated pneumonia in critically Ill children.

Background: Prior antibiotic exposure has been identified as a risk factor for VAP occurrence, making it a growing concern among clinical practitioners. But there is a lack of systematic research on the types of antibiotics and the duration of exposure that influence VAP occurrence in children at current.

Methods: We retrospectively reviewed 278 children admitted to the Pediatric Intensive Care Unit (PICU) and underwent invasive mechanical ventilation (MV) between January 2020 and December 2022. Of these, 171 patients with MV duration ≥ 48 h were included in the study, with 61 of them developing VAP (VAP group) and the remaining 110 as the non-VAP group. We analyzed the relationship between early antibiotic exposure and VAP occurrence.

Results: The incidence of VAP was 21.94% (61/278). The VAP group had significantly longer length of hospital stay (32.00 vs. 20.00 days, p<0.001), PICU stay(25.00 vs. 10.00 days, p<0.001), and duration of mechanical ventilation(16.00 vs. 6.00 days, p<0.001) compared to the non-VAP group. The mortality in the VAP group was significantly higher than that in the non-VAP group (36.07% vs. 21.82%, p = 0.044). The VAP group had a significantly higher rate of carbapenem exposure (65.57% vs. 41.82%, p = 0.003) and duration of usage (9.00 vs. 5.00 days, p = 0.004) than the non-VAP group. Vancomycin and/or linezolid exposure rates (57.38% vs. 40.00%, p = 0.029) and duration (8 vs. 4.5 days, p = 0.010) in the VAP group were significantly higher than that in the non-VAP group, either. Multivariate logistic regression analysis identified the use of carbapenem (≥ 7 days) (OR = 5.156, 95% CI: 1.881-14.137, p = 0.001), repeated intubation (OR = 3.575, 95% CI: 1.449-8.823, p = 0.006), and tracheostomy (OR = 5.767, 95% CI:1.686-19.729, p = 0.005) as the independent risk factors for the occurrence of VAP, while early intravenous immunoglobulin (IVIG) was a protective factor against VAP (OR = 0.426, 95% CI: 0.185-0.98, p = 0.045).

Conclusion: Prior carbapenem exposure (more than 7 days) was an independent risk factor for the occurrence of VAP. For critically ill children, reducing carbapenem use and duration as much as possible should be considered.