The use of mechanical insufflation-exsufflation in invasively ventilated critically ill children.

BACKGROUND: Invasively ventilated, critically ill children are at risk of retained respiratory secretions, which can obstruct airways, impair gas exchange, and cause lung collapse or ventilator-acquired pneumonia. Endotracheal suctioning partially removes secretions, but additional airway clearance interventions may be required. Mechanical insufflation-exsufflation (MI-E), is a cough augmentation device used to improve secretion clearance in adult intensive care, however it is not well characterised in paediatrics. AIM: To explore MI-E use in invasively ventilated, critically ill children. METHOD: This multi-methods study used an anonymous, electronic survey of UK-based paediatric physiotherapists. A scoping review searched seven electronic databases (1995-2025), using key terms ("airway clearance technique*") OR ("mechanical insufflation exsufflation") AND ("mechanical ventilation") OR ("invasive ventilation"). Data were analysed descriptively for both methods, with content analysis for free text survey responses. Mixed-evidence, narrative integration compared and contrasted survey and scoping review findings. RESULTS: Twenty-nine physiotherapists from across the UK completed the survey, 76% (n = 22/29) were advanced specialists, and all reported access to an MI-E device. Six studies (2010-2024), one prospective, the remaining retrospective or case studies, were identified. Both data sources indicated MI-E was most frequently used with acutely unwell neuromuscular patients, though survey responses described a broader clinical application, including children with complex neurological conditions, general respiratory illnesses, trauma, and post-operative surgical or orthopaedic needs. MI-E settings and outcomes were inconsistently reported. Contraindications aligned across sources. CONCLUSIONS: MI-E appears increasingly accessible within paediatric critical care. Future research should assess MI-E safety in intubated patients and investigate broader critically ill populations.