Impact of Respiratory Bacterial Codetection on Outcomes in Ventilated Infants With Bronchiolitis.

Background: Viral bronchiolitis is a common cause of acute respiratory failure requiring intubation for infants. Bacterial respiratory tract infections can occur with bronchiolitis, although their prevalence and impact on outcomes are unclear, especially with increased use of noninvasive respiratory support.

Methods: This was a single-center retrospective cohort study of children <2 years old requiring intubation in the emergency department for bronchiolitis from 2012 to 2017 who had viral testing plus a lower respiratory culture obtained. We evaluated the impact of bacterial codetection (positive respiratory culture plus moderate or many polymorphonuclear neutrophils on Gram stain) on mechanical ventilation (MV) duration and intensive care unit length of stay using multivariable gamma regression.

Results: Of 149 patients enrolled, 52% had bacterial codetection. In adjusted analysis, patients with codetection had shorter MV duration [adjusted relative risk (aRR) 0.819, 95% confidence interval (CI): 0.69-0.98; marginal mean duration of 5.31 days (4.71-5.99) compared to 6.48 days (5.72-7.35) without codetection]. Patients with codetection had a shorter intensive care unit stay [aRR 0.806 (0.69-0.94); marginal mean length of stay 6.9 days (6.21-7.68) vs. 8.57 days (7.68-9.56) without codetection]. The association between codetection and duration of ventilation appears confined to those receiving earlier antibiotics (less than the median time) rather than later antibiotics [aRR 0.738 (0.56-0.95) for earlier vs. aRR 0.92 (0.70-1.18) for later].

Conclusions: Respiratory bacterial codetection is common and associated with shorter MV duration in infants requiring early intubation for bronchiolitis. Early antibiotics may contribute to these outcomes, but further multicenter studies are needed to understand the role of codetection and antibiotics on bronchiolitis outcomes.