title: Evaluation of fully automated ventilation: a randomized controlled study in post-cardiac surgery patients.
abstract: OBJECTIVE
  Discrepancies between the demand and availability of clinicians to care for mechanically ventilated patients can be anticipated due to an aging population and to increasing severity of illness. The use of closed-loop ventilation provides a potential solution. The aim of the study was to evaluate the safety of a fully automated ventilator.
  
  
  METHODS
  We conducted a randomized controlled trial comparing automated ventilation (AV) and protocolized ventilation (PV) in 60 ICU patients after cardiac surgery. In the PV group, tidal volume, respiratory rate, FiO(2) and positive end-expiratory pressure (PEEP) were set according to the local hospital protocol based on currently available guidelines. In the AV group, only sex, patient height and a maximum PEEP level of 10 cmH(2)O were set. The primary endpoint was the duration of ventilation within a "not acceptable" range of tidal volume. Zones of optimal, acceptable and not acceptable ventilation were based on several respiratory parameters and defined a priori.
  
  
  RESULTS
  The patients were assigned equally to each group, 30 to PV and 30 to AV. The percentage of time within the predefined zones of optimal, acceptable and not acceptable ventilation were 12 %, 81 %, and 7 % respectively with PV, and 89.5 %, 10 % and 0.5 % with AV (P < 0.001). There were 148 interventions required during PV compared to only 5 interventions with AV (P < 0.001).
  
  
  CONCLUSIONS
  Fully AV was safe in hemodynamically stable patients immediately following cardiac surgery. In addition to a reduction in the number of interventions, the AV system maintained patients within a predefined target range of optimal ventilation.
authors: Centre de recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, 2725, chemin Sainte-Foy, Quebec City, QC G1V 4G5, Canada. Francois.Lellouche@criucpq.ulaval.ca
authors: François
authors: F
authors: Lellouche
authors: Pierre-Alexandre
authors: PA
authors: Bouchard
authors: Serge
authors: S
authors: Simard
authors: Erwan
authors: E
authors: L'Her
authors: Marc
authors: M
authors: Wysocki
mesh_terms: D000368:Aged; D001331:Automation; D006348:Cardiac Surgical Procedures; D005260:Female; D006801:Humans; D008297:Male; D011182:Postoperative Care / Q000379:methods*; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000379:methods*