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Flow Asynchronies During Pressure Support Ventilation in Children: A Bench Model Study

Meryl Vedrenne-Cloquet1,2, Yukie Ito3, Daniel Chang3

  • 1Dr. Vedrenne-Cloquet is affiliated with Unité de VNI et Sommeil de l'enfant, AP-HP, Hôpital Necker-Enfants malades, Paris, France.

Respiratory Care
|July 1, 2026
PubMed

Insights

Flow asynchrony is common in pediatric mechanical ventilation and varies by ventilator type. Adjusting support can reduce it but may cause other issues, highlighting the need for ventilator-specific management.

Area of Science:

  • Pediatric critical care medicine
  • Respiratory physiology
  • Mechanical ventilation

Background:

  • Flow asynchrony, a type of patient-ventilator asynchrony (PVA), is poorly understood in pediatric intensive care units (PICUs).
  • This PVA type is linked to inadequate ventilator support or excessive patient inspiratory effort.

Purpose of the Study:

  • To investigate if visual patterns of flow asynchrony differ among pediatric ICU ventilators.
  • To determine how support levels and patient inspiratory effort influence flow asynchrony patterns.

Main Methods:

  • A bench study utilized an ASL5000 test lung with models simulating pediatric restrictive and obstructive lung diseases.
  • Four ventilators (AVEA, NKV, C6, ServoU) were tested under pressure-support ventilation (PSV) with varying support and effort levels.
  • Pressure and flow waveforms were analyzed to classify breaths as synchronous, flow asynchrony, double cycling, or ineffective effort.

Main Results:

  • Flow asynchrony occurred in 100% of breaths across all tested ventilators at baseline settings.
  • Increasing support or decreasing effort reduced flow asynchrony but sometimes led to ineffective efforts.
  • The AVEA ventilator demonstrated the quickest reduction in flow asynchrony.

Conclusions:

  • Flow asynchrony is a frequent occurrence during simulated pediatric PSV and is affected by patient effort and ventilator algorithms.
  • Modifying ventilator support to eliminate flow asynchrony may introduce other forms of PVA.
  • Ventilator-specific performance characteristics are crucial for effective PVA management in pediatric patients.
Abstract

Keywords:
mechanical ventilationpatient–ventilator asynchronypediatric critical care

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