Practices and Outcomes in a Brazilian Pediatric Intensive Care Unit After Implementation of a Critical Bronchiolitis...

Critical bronchiolitis is a common reason for pediatric intensive care unit (PICU) admission, and management varies widely, with limited data from South American PICUs. This study aimed to characterize critical bronchiolitis trajectories in a Brazilian PICU and to measure adherence to a clinical protocol deemphasizing ancillary pharmacologic treatments while using the modified Wood-Downes score (mWDS) to guide respiratory support. It also aimed to assess whether admission mWDS would be associated with the need for subsequent invasive mechanical ventilation.

We conducted a retrospective cohort study of infants <24 months admitted with critical bronchiolitis to a Brazilian PICU between March 2021 and April 2023. The protocol was implemented in January 2021 and discouraged the use of inhaled β-agonists, systemic corticosteroids, and inhaled hypertonic saline. It also recommended respiratory support based on the mWDS conventional oxygen for scores ≤3, high-flow nasal cannula (HFNC) or noninvasive ventilation (NIV) for scores 4-7, and consideration of mechanical ventilation for scores >7. We assessed patient characteristics, protocol adherence, and predictive value of admission mWDS for intubation.

Among 299 infants (median age 4.9 mo), 69% had respiratory syncytial virus infection. Maximum respiratory support was conventional oxygen in 61%, HFNC in 22%, NIV in 14%, and mechanical ventilation in 3%. Complete protocol adherence was 43%. Individual component adherence varied: hypertonic saline 100%, corticosteroids 83%, β-agonists 77%, and appropriate respiratory support 54%. Most protocol violations (66%) involved undertreatment with conventional oxygen for mWDS 4-7. The mWDS score at PICU admission was associated with intubation with an area under the curve of 0.77 (95% CI: 0.63-0.91); no subject with mWDS at PICU admission <4 required intubation.

This Brazilian cohort demonstrated low intubation rates despite suboptimal protocol adherence. The mWDS score at PICU admission showed acceptable discrimination for the need for mechanical ventilation, with scores <4 identifying low-risk patients.