What additional management is needed for an infant with a collapsed lower trachea (tracheomalacia) beyond tracheostomy?

Management of Infant with Collapsed Lower Trachea Beyond Tracheostomy

For an infant with collapsed lower trachea (tracheomalacia) identified on bronchoscopy who requires tracheostomy, invasive ventilation (Option C) is the definitive additional management needed to stent open the collapsible distal tracheal segment and ensure adequate ventilation.

Rationale for Invasive Ventilation

The fundamental problem in distal tracheomalacia is that the collapsible airway segment must be mechanically supported to prevent dynamic collapse during respiration. Tracheostomy tube placement alone or in conjunction with prolonged continuous positive airway pressure has been advocated for treatment of tracheomalacia, with the collapsible airway segment ideally residing within the length of the tracheostomy tube for this approach to be effective 1. However, when the collapse involves the lower/distal trachea, a standard tracheostomy tube cannot reach far enough to stent the affected segment.

Why Invasive Ventilation is Required

• Positive pressure ventilation through the tracheostomy provides the necessary distending pressure to prevent collapse of the distal tracheal segment that lies beyond the tip of the tracheostomy tube 1
• The use of elongated tracheostomy tubes has been advocated to allow for stenting of the distal trachea, but this still requires positive pressure support to maintain airway patency 1
• Portable positive pressure ventilators via tracheostomy are the most common method of providing chronic mechanical ventilation in infants with severe airway disease requiring long-term support 1

Why Other Options Are Inadequate

Nasal Cannula (Option A) - Insufficient

• Nasal cannula provides supplemental oxygen but no positive pressure support to stent open a collapsing trachea 1
• The upper airway would need to be patent for nasal oxygen delivery, but more critically, low-flow oxygen cannot generate the distending pressures needed to prevent tracheal collapse
• This option addresses oxygenation but not the mechanical airway obstruction

Non-Invasive Ventilation (Option B) - Anatomically Impossible

• Non-invasive ventilation (BiPAP/CPAP) via nasal or face mask cannot be used in conjunction with a tracheostomy because the air will escape through the tracheostomy stoma rather than reaching the lungs 1
• The guidelines explicitly state that the stoma must be occluded to prevent air escaping via the neck, which would reduce the effectiveness of ventilation when attempting to ventilate via the upper airway 1
• Non-invasive ventilation is not a consideration in conservative management until 6 to 8 years of age at the earliest in stable patients requiring ventilatory support only during sleep 1

Practical Implementation

Ventilator Settings and Management

• Pressure ventilation is preferred using portable home ventilators with continuous flow, as pressure plateau or pressure control mode can compensate for small leaks around the tracheostomy 1
• Target parameters should maintain PetCO2 of 30-50 mm Hg (ideally 35-40 mm Hg) and SpO2 ≥95% to optimize quality of life and preserve energy for developmental activities 1
• A tracheostomy tube smaller than the airway caliber may reduce the likelihood of worsening tracheomalacia while still allowing adequate ventilation 1

Long-Term Considerations

• Weaning from the ventilator is not a realistic goal in severe tracheomalacia requiring this level of support - the focus should be on optimizing ventilator settings to completely meet ventilatory demands 1
• The time from tracheostomy placement to complete discontinuation of mechanical ventilation averages 15.4 months, with median decannulation at 32-37 months in infants requiring chronic ventilation 2
• Infants with acquired airway disease followed in multidisciplinary clinic models may have improved survival, growth, and earlier time to decannulation 2

Critical Pitfalls to Avoid

• Do not attempt non-invasive ventilation via face/nasal mask in a patient with an open tracheostomy - this will result in ineffective ventilation due to air leak through the stoma 1
• Do not underestimate the morbidity and mortality of severe tracheomalacia - it can be associated with life-threatening cyanotic attacks requiring immediate airway stabilization 3
• Ensure a second backup ventilator is available at home for patients dependent on mechanical ventilation to prevent emergency admissions in the event of ventilator failure 1
• Regular assessment of tracheostomy tube sizing is essential - signs that upsizing may be needed include difficulty achieving adequate gas exchange, visible plateau on PetCO2 monitoring, and need for increased ventilator settings 1