Comparative Effects of Variable Pressure Support, Neurally Adjusted Ventilatory Assist (NAVA) and Proportional Assist Ventilation (PAV) on the Variability of the Breathing Pattern and on Patient Ventilator Interaction
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Respiratory Failure
- Sponsor
- Association pour le Développement et l'Organisation de la Recherche en Pneumologie et sur le Sommeil
- Enrollment
- 12
- Locations
- 1
- Primary Endpoint
- Coefficient of variation of the tidal volume (VT)
- Status
- Completed
- Last Updated
- 10 years ago
Overview
Brief Summary
Experimental animal data suggest that increasing breathing pattern variability in mechanical ventilation could be beneficial. Variable ventilation can be induced through the following modes: Neurally Adjust Ventilatory Assist (NAVA), Proportional Assist Ventilation (PAV) and Variable-Pressure Support Ventilation (V-PSV). These modes have not yet been compared to each other. Pilot observations in our department suggest a feasibility in patients.
The objectives of the study are to compare the impact of PSV, NAVA, PAV and V-PSV on the variability of the breathing pattern, patient-ventilator asynchrony, risk of lung overdistension, gas exchange, and repartition of ventilation.
Detailed Description
Cross-over, prospective, randomized controlled monocentric trial . Patients on pressure support ventilation will be ventilated with PSV, NAVA, PAV, and V-PSV (in a randomized sequence). In each mode the level of assistance will be set to achieve a similar tidal volume of 6-8 ml/kg. The following data will be measured and recorded: airway flow and pressure, electrical activity of the diaphragm (EAdi), blood gases, electrical impedance tomography, end tidal partial pressure in carbon dioxide (PEtCO2). Will be calculated: the coefficient of variation (CV, standard deviation (SD)/mean) of the peak pressure (Ppeak), EAdi and of the main descriptors of the breathing pattern, the prevalence of the main patient-ventilator asynchronies, the prevalence of tidal volume (VT) \>10ml/kg, ventrodorsal repartition of ventilation and inhomogeneity index, dead space
Investigators
Eligibility Criteria
Inclusion Criteria
- •patient on mechanical ventilation for \>48 h
- •estimated duration of mechanical ventilation \>24h
- •hemodynamic stability
Exclusion Criteria
- •pregnancy
- •impossibility to insert an EAdi catheter
- •neuromuscular disease, phrenic nerve lesions
Outcomes
Primary Outcomes
Coefficient of variation of the tidal volume (VT)
Time Frame: 1 hour
Coefficient of variation (standard deviation/mean) of the tidal volume (VT)
Coefficient of variation of the inspiratory time (Ti)
Time Frame: 1 hour
Coefficient of variation (standard deviation/mean) of the inspiratory time (Ti)
Coefficient of variation of the maximal inspiratory pressure (Ppeak)
Time Frame: 1 hour
Coefficient of variation (standard deviation/mean) of the maximal inspiratory pressure (Ppeak)
Coefficient of variation of the electrical activity of the diaphragm (EAdi)
Time Frame: 1 hour
Coefficient of variation (standard deviation/mean) of the electrical activity of the diaphragm (EAdi)
Coefficient of variation of the respiratory rate (RR)
Time Frame: 1 hour
Coefficient of variation (standard deviation/mean) of the respiratory rate (RR)
Secondary Outcomes
- Dead space to tidal volume ratio (Vd/Vt)(6 hours)
- Safety from lung overdistension, assessed by the proportion of tidal volumes (VT) >10 ml/kg(1 hour)
- Gas exchanges(6 hours)
- Repartition of ventilation measured by electrical impedance tomography(6 hours)
- Patient ventilator asynchrony(1 hour)