Maria Plataki1, Rolf D Hubmayr. 1. Thoracic Diseases Research Unit, Division of Pulmonary and Critical Care Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA.
Abstract
PURPOSE OF REVIEW: Despite the well recognized role of mechanical ventilation in lung injury, appropriate surrogate markers to guide titration of ventilator settings remain elusive. One would like to strike a balance between protecting aerated units from overdistension while recruiting unstable units, thereby reducing tissue damage associated with their cyclic recruitment and derecruitment. To do so requires some estimate of the topographical distribution of parenchymal stress and strain. RECENT FINDINGS: Recent studies have highlighted the importance of chest wall recoil and its effect on pleural pressure (Ppl) in determining lung stress. Although esophageal pressure (Pes) has traditionally been used to measure the average Ppl in normal upright patients, in recumbent acute lung injury/acute respiratory distress syndrome patients Pes-based estimates of Ppl are subject to untestable assumptions. Nevertheless, Pes measurements in recumbent patients with injured lungs strongly suggest that Ppl over dependent parts of the lung can exceed airway pressure by substantial amounts. Moreover, results of a pilot study in which Pes was used to titrate positive end-expiratory pressure (PEEP) suggest clinical benefit. SUMMARY: Notwithstanding its theoretical limitations, esophageal manometry has shown promise in PEEP titration and deserves further evaluation in a larger trial on patients with injured lungs.
PURPOSE OF REVIEW: Despite the well recognized role of mechanical ventilation in lung injury, appropriate surrogate markers to guide titration of ventilator settings remain elusive. One would like to strike a balance between protecting aerated units from overdistension while recruiting unstable units, thereby reducing tissue damage associated with their cyclic recruitment and derecruitment. To do so requires some estimate of the topographical distribution of parenchymal stress and strain. RECENT FINDINGS: Recent studies have highlighted the importance of chest wall recoil and its effect on pleural pressure (Ppl) in determining lung stress. Although esophageal pressure (Pes) has traditionally been used to measure the average Ppl in normal upright patients, in recumbent acute lung injury/acute respiratory distress syndromepatients Pes-based estimates of Ppl are subject to untestable assumptions. Nevertheless, Pes measurements in recumbent patients with injured lungs strongly suggest that Ppl over dependent parts of the lung can exceed airway pressure by substantial amounts. Moreover, results of a pilot study in which Pes was used to titrate positive end-expiratory pressure (PEEP) suggest clinical benefit. SUMMARY: Notwithstanding its theoretical limitations, esophageal manometry has shown promise in PEEP titration and deserves further evaluation in a larger trial on patients with injured lungs.
Authors: Stephen H Loring; Matteo Pecchiari; Patrizia Della Valle; Ario Monaco; Guendalina Gentile; Edgardo D'Angelo Journal: Crit Care Med Date: 2010-12 Impact factor: 7.598
Authors: Roy G Brower; Michael A Matthay; Alan Morris; David Schoenfeld; B Taylor Thompson; Arthur Wheeler Journal: N Engl J Med Date: 2000-05-04 Impact factor: 91.245
Authors: Matthias Briel; Maureen Meade; Alain Mercat; Roy G Brower; Daniel Talmor; Stephen D Walter; Arthur S Slutsky; Eleanor Pullenayegum; Qi Zhou; Deborah Cook; Laurent Brochard; Jean-Christophe M Richard; Francois Lamontagne; Neera Bhatnagar; Thomas E Stewart; Gordon Guyatt Journal: JAMA Date: 2010-03-03 Impact factor: 56.272
Authors: Stephen H Loring; Carl R O'Donnell; Negin Behazin; Atul Malhotra; Todd Sarge; Ray Ritz; Victor Novack; Daniel Talmor Journal: J Appl Physiol (1985) Date: 2009-12-17
Authors: Brian D Kubiak; Louis A Gatto; Edgar J Jimenez; Hugo Silva-Parra; Kathleen P Snyder; Christopher J Vieau; Jorge Barba; Niloofar Nasseri-Nik; Jay L Falk; Gary F Nieman Journal: J Surg Res Date: 2009-09-05 Impact factor: 2.192