title: Automatic selection of breathing pattern using adaptive support ventilation.
abstract: OBJECTIVE
  In a cohort of mechanically ventilated patients to compare the automatic tidal volume (VT)-respiratory rate (RR) combination generated by adaptive support ventilation (ASV) for various lung conditions.
  
  
  METHODS
  Prospective observational cohort study in the 11-bed medicosurgical ICU of a general hospital.
  
  
  METHODS
  243 patients receiving 1327 days of invasive ventilation on ASV.
  
  
  METHODS
  Daily collection of ventilator settings, breathing pattern, arterial blood gases, and underlying clinical respiratory conditions categorized as: normal lungs, ALI/ARDS, COPD, chest wall stiffness, or acute respiratory failure.
  
  
  RESULTS
  Overall the respiratory mechanics differed significantly with the underlying conditions. In passive patients ASV delivered different VT-RR combinations based on the underlying condition, providing higher VT and lower RR in COPD than in ALI/ARDS: 9.3ml/kg (8.2-10.8) predicted body weight (PBW) and 13 breaths/min (11-16) vs. 7.6ml/kg (6.7-8.8) PBW and 18 breaths/min (16-22). In patients actively triggering the ventilator the VT-RR combinations did not differ between COPD, ALI/ARDS, and normal lungs.
  
  
  CONCLUSIONS
  ASV selects different VT-RR combinations based on respiratory mechanics in passive, mechanically ventilated patients.
authors.affiliation: Hôpital Font Pré, Service de réanimation polyvalente, 1208 avenue du colonel Picot, 83100 Toulon, France. jean-michel@arnal.org
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Arnal
authors.forename: Marc
authors.initials: M
authors.lastname: Wysocki
authors.forename: Cyril
authors.initials: C
authors.lastname: Nafati
authors.forename: Stéphane
authors.initials: S
authors.lastname: Donati
authors.forename: Isabelle
authors.initials: I
authors.lastname: Granier
authors.forename: Gaëlle
authors.initials: G
authors.lastname: Corno
authors.forename: Jacques
authors.initials: J
authors.lastname: Durand-Gasselin
mesh_terms: D000368:Aged; D003422:Critical Care; D005260:Female; D005602:France; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology; D012121:Respiration, Artificial / Q000379:methods*; D012128:Respiratory Distress Syndrome / Q000503:physiopathology; D015656:Respiratory Mechanics / Q000502:physiology*; D013990:Tidal Volume / Q000502:physiology