title: Implementing a bedside assessment of respiratory mechanics in patients with acute respiratory distress syndrome.
abstract: Despite their potential interest for clinical management, measurements of respiratory mechanics in patients with acute respiratory distress syndrome (ARDS) are seldom performed in routine practice. We introduced a systematic assessment of respiratory mechanics in our clinical practice. After the first year of clinical use, we retrospectively assessed whether these measurements had any influence on clinical management and physiological parameters associated with clinical outcomes by comparing their value before and after performing the test.
  
  
  
  The respiratory mechanics assessment constituted a set of bedside measurements to determine passive lung and chest wall mechanics, response to positive end-expiratory pressure, and alveolar derecruitment. It was obtained early after ARDS diagnosis. The results were provided to the clinical team to be used at their own discretion. We compared ventilator settings and physiological variables before and after the test. The physiological endpoints were oxygenation index, dead space, and plateau and driving pressures.
  
  
  
  Sixty-one consecutive patients with ARDS were enrolled. Esophageal pressure was measured in 53 patients (86.9%). In 41 patients (67.2%), ventilator settings were changed after the measurements, often by reducing positive end-expiratory pressure or by switching pressure-targeted mode to volume-targeted mode. Following changes, the oxygenation index, airway plateau, and driving pressures were significantly improved, whereas the dead-space fraction remained unchanged. The oxygenation index continued to improve in the next 48 h.
  
  
  
  Implementing a systematic respiratory mechanics test leads to frequent individual adaptations of ventilator settings and allows improvement in oxygenation indexes and reduction of the risk of overdistention at the same time.
  
  
  
  The present study involves data from our ongoing registry for respiratory mechanics (ClinicalTrials.gov identifier: NCT02623192 . Registered 30 July 2015).
authors.affiliation: Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.|Keenan Research Centre and Li Ka Shing Institute, Department of Critical Care, St. Michael's Hospital, 209 Victoria Street, Room 408, Toronto, ON, M5B 1T8, Canada.
authors.forename: Lu
authors.initials: L
authors.lastname: Chen
authors.affiliation: Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.|Keenan Research Centre and Li Ka Shing Institute, Department of Critical Care, St. Michael's Hospital, 209 Victoria Street, Room 408, Toronto, ON, M5B 1T8, Canada.|Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Guang-Qiang
authors.initials: GQ
authors.lastname: Chen
authors.affiliation: Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.
authors.forename: Kevin
authors.initials: K
authors.lastname: Shore
authors.affiliation: Department of Respiratory Therapy, St. Michael's Hospital, Toronto, ON, Canada.
authors.forename: Orest
authors.initials: O
authors.lastname: Shklar
authors.affiliation: Department of Respiratory Therapy, St. Michael's Hospital, Toronto, ON, Canada.
authors.forename: Concetta
authors.initials: C
authors.lastname: Martins
authors.affiliation: Department of Respiratory Therapy, St. Michael's Hospital, Toronto, ON, Canada.
authors.forename: Brian
authors.initials: B
authors.lastname: Devenyi
authors.affiliation: Department of Respiratory Therapy, St. Michael's Hospital, Toronto, ON, Canada.
authors.forename: Paul
authors.initials: P
authors.lastname: Lindsay
authors.affiliation: Department of Respiratory Therapy, St. Michael's Hospital, Toronto, ON, Canada.
authors.forename: Heather
authors.initials: H
authors.lastname: McPhail
authors.affiliation: Keenan Research Centre and Li Ka Shing Institute, Department of Critical Care, St. Michael's Hospital, 209 Victoria Street, Room 408, Toronto, ON, M5B 1T8, Canada.
authors.forename: Ashley
authors.initials: A
authors.lastname: Lanys
authors.affiliation: Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Soliman
authors.affiliation: Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.
authors.forename: Mazin
authors.initials: M
authors.lastname: Tuma
authors.affiliation: Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Kim
authors.affiliation: Department of Respiratory Therapy, St. Michael's Hospital, Toronto, ON, Canada.
authors.forename: Kerri
authors.initials: K
authors.lastname: Porretta
authors.affiliation: Department of Respiratory Therapy, St. Michael's Hospital, Toronto, ON, Canada.
authors.forename: Pamela
authors.initials: P
authors.lastname: Greco
authors.affiliation: Department of Respiratory Therapy, St. Michael's Hospital, Toronto, ON, Canada.
authors.forename: Hilary
authors.initials: H
authors.lastname: Every
authors.affiliation: Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.|Keenan Research Centre and Li Ka Shing Institute, Department of Critical Care, St. Michael's Hospital, 209 Victoria Street, Room 408, Toronto, ON, M5B 1T8, Canada.
authors.forename: Chris
authors.initials: C
authors.lastname: Hayes
authors.affiliation: Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.|Keenan Research Centre and Li Ka Shing Institute, Department of Critical Care, St. Michael's Hospital, 209 Victoria Street, Room 408, Toronto, ON, M5B 1T8, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Baker
authors.affiliation: Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.|Keenan Research Centre and Li Ka Shing Institute, Department of Critical Care, St. Michael's Hospital, 209 Victoria Street, Room 408, Toronto, ON, M5B 1T8, Canada.
authors.forename: Jan O
authors.initials: JO
authors.lastname: Friedrich
authors.affiliation: Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada. brochardl@smh.ca.|Keenan Research Centre and Li Ka Shing Institute, Department of Critical Care, St. Michael's Hospital, 209 Victoria Street, Room 408, Toronto, ON, M5B 1T8, Canada. brochardl@smh.ca.
authors.forename: Laurent
authors.initials: L
authors.lastname: Brochard
mesh_terms: D000368:Aged; D002986:Clinical Trials as Topic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000067716:Point-of-Care Testing; D010818:Practice Patterns, Physicians' / Q000592:standards; D012121:Respiration, Artificial / Q000379:methods / Q000592:standards; D012128:Respiratory Distress Syndrome / Q000175:diagnosis*; D015656:Respiratory Mechanics / Q000502:physiology*; D012189:Retrospective Studies; D014894:Weights and Measures / Q000592:standards*
keywords: Esophageal pressure; Mechanical ventilation; Pulmonary function test; Quality improvement; Respiratory physiology