Comparison of Work of Breathing Between Noninvasive Ventilation and Neurally Adjusted Ventilatory Assist in a Healthy and a Lung-Injured Piglet Model

Respir Care. 2018 Dec;63(12):1478-1484. doi: 10.4187/respcare.06192. Epub 2018 Sep 25.

Abstract

Background: Noninvasive ventilation (NIV) is commonly used in neonates. A mode of NIV called neurally adjusted ventilatory assist (NAVA) offers patient-ventilator interactions by using electrical activity of the diaphragm to control mechanical breaths. We hypothesized that the work of breathing (WOB) would decrease with NIV-NAVA. Secondary objectives evaluated the impact of NIV-NAVA on arterial blood gases and respiratory parameters.

Methods: We compared WOB between synchronized breaths in NIV-NAVA and NIV in piglets with healthy lungs and then with surfactant-depleted lungs. Neonatal pigs (median, 2.0 [range, 1.8-2.4] kg) with healthy and then surfactant depleted lungs were sedated and ventilated with NIV-NAVA and NIV in random order. Airway flow and pressure waveforms were acquired. Waveforms were analyzed for the pressure-time product that reflected WOB. The primary outcome between modes was assessed with repeated measurement analysis of variance.

Results: The pressure-time product was significantly decreased for NIV-NAVA in both healthy and injured lungs (P < .001). PaO2 , PaCO2 , inspiratory tidal volume, and peak inspiratory flow were not different in either model.

Conclusions: Synchronized breaths during NIV-NAVA resulted in decreased WOB compared with synchronized breaths during NIV.

Keywords: NAVA; NIV; neurally adjusted ventilatory assist; noninvasive ventilation; respiratory physiology; work of breathing.

Publication types

  • Comparative Study

MeSH terms

  • Air Pressure
  • Animals
  • Carbon Dioxide / blood
  • Interactive Ventilatory Support*
  • Lung Injury / physiopathology*
  • Male
  • Noninvasive Ventilation / methods*
  • Oxygen / blood
  • Partial Pressure
  • Random Allocation
  • Swine
  • Time Factors
  • Work of Breathing*

Substances

  • Carbon Dioxide
  • Oxygen