Respiratory morbidity 6 to 12 months after mechanical ventilation for life-threatening respiratory syncytial virus infection.

Background: Respiratory morbidity in infants with life-threatening respiratory syncytial virus (RSV) infection necessitating invasive mechanical ventilation (MV) is underexplored. We therefore sought to characterise infant respiratory morbidity and pulmonary function 6 to 12 months after paediatric intensive care unit (PICU) discharge. Methods: We invited 463 infants with RSV bronchiolitis necessitating MV (December 2011 to January 2023) for clinical assessments (structured interview, physical examination) and pulmonary function testing using whole-body plethysmography and multiple breath washout (from 2016 onwards). Subjects were dichotomised by maximal expiratory flow at the functional residual capacity ( Results: Data from 219 out of 463 subjects (47.3%) were available for analysis (mean±sd age at follow-up 50±16 weeks and 40.3±14.2 weeks since PICU discharge). 180 (82.2%) subjects had parent-reported respiratory symptoms and 68 (31.1%) used bronchodilator treatment as needed. For the whole cohort, mean±sd FRCp z-score was 1.0±1.5 and Conclusions: Evidence of small airway dysfunction was found in almost one-third of subjects who have been ventilated for life-threatening RSV disease, although not always accompanied by respiratory symptoms.