title: Respiratory muscle unloading during auto-adaptive non-invasive ventilation.
abstract: BACKGROUND
  Non-invasive ventilation (NIV) has been shown to improve clinical outcomes in acute and chronic hypercapnic respiratory failure. A new timed, automated, auto-adaptive non-invasive ventilatory mode (TA-mode) has been recently introduced.
  
  
  OBJECTIVE
  To investigate the degree of respiratory muscle unloading with this new mode in comparison to assisted (S-mode) NIV in healthy individuals.
  
  
  METHODS
  Work of breathing, pressure time product and transdiaphragmatic pressure time product were measured during unassisted breathing, assisted and TA-mode-NIV in eight healthy, awake volunteers at inspiratory pressures of 20 and expiratory pressures of 4hPa.
  
  
  RESULTS
  Assisted and TA-mode-NIV reduced the work of breathing by 50 and 89.1%, pressure time product by 61.5 and 72.6% and transdiaphragmatic pressure time product by 77 and 88.7%, respectively when compared to unassisted breathing. The degree of respiratory muscle unloading was higher during TA-mode-NIV when compared to assisted non-invasive ventilation (work of breathing p<0.001, pressure time product p=0.04 and transdiaphragmatic pressure time product p=0,01).
  
  
  CONCLUSIONS
  TA-mode-NIV achieved significant higher levels of respiratory muscle unloading in healthy individuals when compared to assisted non-invasive ventilation.
authors.affiliation: Kloster Grafschaft, Schmallenberg, Germany. d.dellweg@fkkg.de
authors.forename: Dominic
authors.initials: D
authors.lastname: Dellweg
authors.forename: Thomas
authors.initials: T
authors.lastname: Barchfeld
authors.forename: Matthias
authors.initials: M
authors.lastname: Klauke
authors.forename: Glenn
authors.initials: G
authors.lastname: Eiger
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008170:Lung Compliance; D008297:Male; D008397:Masks; D008954:Models, Biological; D010865:Pilot Projects; D011175:Positive-Pressure Respiration / Q000295:instrumentation*; D012131:Respiratory Insufficiency / Q000503:physiopathology* / Q000534:rehabilitation; D015656:Respiratory Mechanics / Q000502:physiology*; D012132:Respiratory Muscles / Q000502:physiology*; D013813:Therapy, Computer-Assisted / Q000379:methods; D016896:Treatment Outcome; D014939:Work of Breathing / Q000502:physiology*