title: Neurally adjusted ventilatory assist and proportional assist ventilation both improve patient-ventilator interaction.
abstract: BACKGROUND
  The objective was to compare the impact of three assistance levels of different modes of mechanical ventilation; neurally adjusted ventilatory assist (NAVA), proportional assist ventilation (PAV), and pressure support ventilation (PSV) on major features of patient-ventilator interaction.
  
  
  METHODS
  PSV, NAVA, and PAV were set to obtain a tidal volume (VT) of 6 to 8 ml/kg (PSV₁₀₀, NAVA₁₀₀, and PAV₁₀₀) in 16 intubated patients. Assistance was further decreased by 50% (PSV₅₀, NAVA₅₀, and PAV₅₀) and then increased by 50% (PSV₁₅₀, NAVA₁₅₀, and PAV₁₅₀) with all modes. The three modes were randomly applied. Airway flow and pressure, electrical activity of the diaphragm (EAdi), and blood gases were measured. VT, peak EAdi, coefficient of variation of VT and EAdi, and the prevalence of the main patient-ventilator asynchronies were calculated.
  
  
  RESULTS
  PAV and NAVA prevented the increase of VT with high levels of assistance (median 7.4 (interquartile range (IQR) 5.7 to 10.1) ml/kg and 7.4 (IQR, 5.9 to 10.5) ml/kg with PAV₁₅₀ and NAVA₁₅₀ versus 10.9 (IQR, 8.9 to 12.0) ml/kg with PSV₁₅₀, P <0.05). EAdi was higher with PAV than with PSV at level₁₀₀ and level₁₅₀. The coefficient of variation of VT was higher with NAVA and PAV (19 (IQR, 14 to 31)% and 21 (IQR 16 to 29)% with NAVA₁₀₀ and PAV₁₀₀ versus 13 (IQR 11 to 18)% with PSV₁₀₀, P <0.05). The prevalence of ineffective triggering was lower with PAV and NAVA than with PSV (P <0.05), but the prevalence of double triggering was higher with NAVA than with PAV and PSV (P <0.05).
  
  
  CONCLUSIONS
  PAV and NAVA both prevent overdistention, improve neuromechanical coupling, restore the variability of the breathing pattern, and decrease patient-ventilator asynchrony in fairly similar ways compared with PSV. Further studies are needed to evaluate the possible clinical benefits of NAVA and PAV on clinical outcomes.
  
  
  BACKGROUND
  Clinicaltrials.gov NCT02056093 . Registered 18 December 2013.
authors: Sorbonne Universités, UPMC Univ Paris 06, UMR_S 1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France. matthieuschmidt@yahoo.fr.|INSERM, UMR_S 1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France. matthieuschmidt@yahoo.fr.|AP-HP, Groupe Hospitalier Pitié-Salpêtrière Charles Foix, Service de Pneumologie et Réanimation Médicale (Département R3S), F-75013, Paris, France. matthieuschmidt@yahoo.fr.|Service de Pneumologie et Réanimation Médicale, Groupe Hospitalier Pitié-Salpêtrière, 47-83 boulevard de l'Hôpital, 75651, Paris, Cedex 13, France. matthieuschmidt@yahoo.fr.
authors: Matthieu
authors: M
authors: Schmidt
authors: AP-HP, Groupe Hospitalier Pitié-Salpêtrière Charles Foix, Service de Pneumologie et Réanimation Médicale (Département R3S), F-75013, Paris, France. felix.kindler@gmail.com.
authors: Felix
authors: F
authors: Kindler
authors: Sorbonne Universités, UPMC Univ Paris 06, UMR_S 1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France. jcecchini11@orange.fr.|INSERM, UMR_S 1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France. jcecchini11@orange.fr.
authors: Jérôme
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authors: Cecchini
authors: Université Pierre et Marie Curie-CNRS-INSERM, ICM, Equipe Neurologie et Thérapeutique Expérimentale, Hôpital de la Salpêtrière, Paris, France. itym@me.com.
authors: Tymothée
authors: T
authors: Poitou
authors: Sorbonne Universités, UPMC Univ Paris 06, UMR_S 1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France. elisemorawiec@gmail.com.|INSERM, UMR_S 1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France. elisemorawiec@gmail.com.|AP-HP, Groupe Hospitalier Pitié-Salpêtrière Charles Foix, Service de Pneumologie et Réanimation Médicale (Département R3S), F-75013, Paris, France. elisemorawiec@gmail.com.
authors: Elise
authors: E
authors: Morawiec
authors: AP-HP, Groupe Hospitalier Pitié-Salpêtrière Charles Foix, Service de Pneumologie et Réanimation Médicale (Département R3S), F-75013, Paris, France. romain.persichini@hotmail.fr.
authors: Romain
authors: R
authors: Persichini
authors: Sorbonne Universités, UPMC Univ Paris 06, UMR_S 1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France. thomas.similowski@psl.aphp.fr.|INSERM, UMR_S 1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France. thomas.similowski@psl.aphp.fr.|AP-HP, Groupe Hospitalier Pitié-Salpêtrière Charles Foix, Service de Pneumologie et Réanimation Médicale (Département R3S), F-75013, Paris, France. thomas.similowski@psl.aphp.fr.
authors: Thomas
authors: T
authors: Similowski
authors: Sorbonne Universités, UPMC Univ Paris 06, UMR_S 1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France. alexandre.demoule@psl.aphp.fr.|INSERM, UMR_S 1158 Neurophysiologie Respiratoire Expérimentale et Clinique, F-75005, Paris, France. alexandre.demoule@psl.aphp.fr.|AP-HP, Groupe Hospitalier Pitié-Salpêtrière Charles Foix, Service de Pneumologie et Réanimation Médicale (Département R3S), F-75013, Paris, France. alexandre.demoule@psl.aphp.fr.|U974, Institut National de la Santé et de la Recherche médicale, Paris, France. alexandre.demoule@psl.aphp.fr.
authors: Alexandre
authors: A
authors: Demoule
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001784:Blood Gas Analysis; D003422:Critical Care / Q000379:methods*; D003964:Diaphragm / Q000294:innervation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009424:Nervous System Physiological Phenomena; D011897:Random Allocation; D012121:Respiration, Artificial / Q000295:instrumentation / Q000379:methods*; D012131:Respiratory Insufficiency / Q000628:therapy*; D015656:Respiratory Mechanics / Q000502:physiology; D012132:Respiratory Muscles / Q000502:physiology; D013990:Tidal Volume / Q000502:physiology