Imprecision in lower 'inflection point' estimation from static pressure- volume curves in patients at risk for acute respiratory distress syndrome

Grant E. O'Keefe, Larry M. Gentilello, Shelly Erford, Ronald V. Maier

Research output: Contribution to journalArticle

23 Scopus citations


Background: Static pressure-volume (PV) curves have been promoted as a tool for selecting positive end-expiratory pressure (PEEP) by identifying a lower 'inflection point' (P(flex)) from these curves. Their visual interpretation is subjective and difficult, however, particularly with subtle changes in the slope of the curves. This study was designed to examine the physician-to-physician variability in estimating the lower P(flex) from these curves. Methods: Static PV curves for eight patients were obtained within 24 hours of admission. Five intensivists and one respiratory therapist independently estimated the lower P(flex) from these curves. Results: P(flex) estimates for individual patients were highly variable, ranging from 5 to 9 cm H2O. This variability was not attributable to a single discordant estimate, nor was a single physician responsible for consistently high or low estimates. Conclusion: Static PV curve interpretation with current methods imprecisely estimates the lower inflection point and is of limited usefulness in PEEP selection.

Original languageEnglish (US)
Pages (from-to)1065-1068
Number of pages4
JournalJournal of Trauma - Injury, Infection and Critical Care
Issue number6
StatePublished - Jun 1998



  • ARDS
  • Mechanical ventilation
  • Respiratory failure

ASJC Scopus subject areas

  • Surgery
  • Critical Care and Intensive Care Medicine

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