title: The effect of the pressure-volume curve for positive end-expiratory pressure titration on clinical outcomes in acute respiratory distress syndrome: a systematic review.
abstract: OBJECTIVE
  Methods to optimize positive end-expiratory pressure (PEEP) in acute respiratory distress syndrome (ARDS) remain controversial despite decades of research. The pressure-volume curve (PVC), a graphical ventilator relationship, has been proposed for prescription of PEEP in ARDS. Whether the use of PVC's improves survival remains unclear.
  
  
  METHODS
  In this systematic review, we assessed randomized controlled trials (RCTs) comparing PVC-guided treatment with conventional PEEP management on survival in ARDS based on the search of the National Library of Medicine from January 1, 1960, to January 1, 2010, and the Cochrane Central Register of Controlled Trials. Three RCTs were identified with a total of 185 patients, 97 with PVC-guided treatment and 88 with conventional PEEP management.
  
  
  RESULTS
  The PVC-guided PEEP was associated with an increased probability of 28-day or hospital survival (odds ratio [OR] 2.7, 95% confidence interval [CI] 1.5, 4.9) using a random-effects model without significant heterogeneity (I (2) test: P = .75). The PVC-guided ventilator support was associated with reduced cumulative risk of mortality (-0.24 (95% CI -0.38, -0.11). The PVC-managed patients received greater PEEP (standardized mean difference [SMD] 5.7 cm H2O, 95% CI 2.4, 9.0) and lower plateau pressures (SMD -1.2 cm H2O, 95% CI -2.2, -0.2), albeit with greater hypercapnia with increased arterial pCO2 (SMD 8 mm Hg, 95% CI 2, 14). Weight-adjusted tidal volumes were significantly lower in PVC-guided than conventional ventilator management (SMD 2.6 mL/kg, 95% CI -3.3, -2.0).
  
  
  CONCLUSIONS
  This analysis supports an association that ventilator management guided by the PVC for PEEP management may augment survival in ARDS. Nonetheless, only 3 randomized trials have addressed the question, and the total number of patients remains low. Further outcomes studies appear required for the validation of this methodology.
authors.affiliation: Departments of Outcomes Research, Cardiac Anesthesiology, and General Anesthesiology, Center for Critical Care, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA Department of Cardiac Anesthesiology, Center for Critical Care Medicine, Cleveland Clinic, Cleveland, OH, USA Department of General Anesthesiology, Center for Critical Care Medicine, Cleveland Clinic, Cleveland, OH, USA Anesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA hataj@ccf.org.
authors.forename: J Steven
authors.initials: JS
authors.lastname: Hata
authors.affiliation: Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA, USA.
authors.forename: Kei
authors.initials: K
authors.lastname: Togashi
authors.affiliation: Division of Critical Care in the Department of Anesthesia, University of Vanderbilt, Nashville, TN, USA.
authors.forename: Avinash B
authors.initials: AB
authors.lastname: Kumar
authors.affiliation: Imperial Drive, O'Fallon, MO, USA.
authors.forename: Linda D
authors.initials: LD
authors.lastname: Hodges
authors.affiliation: Department of Cardiac Anesthesiology, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Eric F
authors.initials: EF
authors.lastname: Kaiser
authors.affiliation: Division of Cardiothoracic Surgery, University of Florida; Gainesville, FL, USA.
authors.forename: Paul B
authors.initials: PB
authors.lastname: Tessmann
authors.affiliation: Department of Anesthesiology, University of Iowa, Iowa City, IA, USA.
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Faust
authors.affiliation: Department of Outcomes Research, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Daniel I
authors.initials: DI
authors.lastname: Sessler
mesh_terms: D003422:Critical Care / Q000379:methods*; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data*; D010101:Oxygen Consumption; D011175:Positive-Pressure Respiration / Q000295:instrumentation / Q000401:mortality; D016032:Randomized Controlled Trials as Topic; D012128:Respiratory Distress Syndrome / Q000401:mortality / Q000628:therapy*; D016019:Survival Analysis; D013990:Tidal Volume; D016896:Treatment Outcome; D055397:Ventilator-Induced Lung Injury / Q000401:mortality / Q000517:prevention & control*
keywords: acute respiratory distress syndrome; mechanical ventilation; positive end expiratory pressure; systematic review