Ventilator settings as a risk factor for acute respiratory distress syndrome in mechanically ventilated patients
- 1.3k Downloads
A single-center retrospective study initial recently identified ventilator settings as a major risk factor for the development of acute respiratory distress syndrome (ARDS) in mechanically ventilated patients who do not have ARDS from the outset. We tested this hypothesis in a larger sample of patients prospectively enrolled in a multicenter study on mechanical ventilation.
Design and setting
From a large international mechanical ventilation study database we identified patients who required mechanical ventilation for 48 h or more but did not have ARDS at the onset of mechanical ventilation. We extracted information on demographics, initial severity of illness, ventilator settings and major underlying ARDS risk factors. Primary outcome was development of ARDS after the onset of mechanical ventilation.
Measurements and results
Of 3,261 mechanically ventilated patients who did not have ARDS at the outset 205 (6.2%) developed ARDS 48 h or more after the onset of mechanical ventilation. Multivariate logistic regression analysis adjusted for baseline patient characteristics (age, gender, Simplified Acute Physiology Score, hypoxemia) and underlying ARDS risk factors (sepsis, trauma, pneumonia) found the development of ARDS to be associated with the initial ventilator settings: high tidal volume (odds ratio 2.6 for tidal volume >700 ml), high peak airway pressure (odds ratio 1.6 for peak airway pressure >30 cmH2O), and high positive end-expiratory pressure (odds ratio 1.7 for end-expiratory pressure >5 cmH2O).
The association with the potentially injurious initial ventilator settings, in particular large tidal volumes, suggests that ARDS in mechanically ventilated patients is in part a preventable complication. This hypothesis needs to be tested in a prospective study.
KeywordsRespiration Artificial, adverse effects Respiratory distress syndrome, adult Pulmonary edema, pneumonia
Appendix 1 List of investigators
- 1.Goss CH, Brower RG, Hudson LD, Rubenfeld GD (2003) Incidence of acute lung injury in the United States. Crit Care Med 31:1607–1611Google Scholar
- 2.Ware LB, Matthay MA (2000) The acute respiratory distress syndrome. N Engl J Med 342:1334–1349Google Scholar
- 3.Hudson LD, Milberg JA, Anardi D, Maunder RJ (1995) Clinical risks for development of the acute respiratory distress syndrome. Am J Respir Crit Care Med 151:293–301Google Scholar
- 4.Pepe PE, Potkin RT, Reus DH, Hudson LD, Carrico CJ (1982) Clinical predictors of the adult respiratory distress syndrome. Am J Surg 144:124–130Google Scholar
- 5.1999 International consensus conferences in intensive care medicine (1999) Ventilator-associated lung injury in ARDS. This official conference report was cosponsored by the American Thoracic Society, The European Society of Intensive Care Medicine, and The Societe de Reanimation de Langue Francaise, and was approved by the ATS Board of Directors, July 1999. Am J Respir Crit Care Med 160:2118–2124Google Scholar
- 6.Dreyfuss D, Basset G, Soler P, Saumon G (1985) Intermittent positive-pressure hyperventilation with high inflation pressures produces pulmonary microvascular injury in rats. Am Rev Respir Dis 132:880–884Google Scholar
- 7.Gajic O, Lee J, Doerr CH, Berrios JC, Myers JL, Hubmayr RD (2003) Ventilator-induced cell wounding and repair in the intact lung. Am J Respir Crit Care Med 167:1057–1063Google Scholar
- 8.The Acute Respiratory Distress Syndrome Network (2000) Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. N Engl J Med 342:1301–1308Google Scholar
- 9.Gajic O, Dara S, Mendez J, Adesanya A, Festic E, Caples S, Rana R, St Sauver J, Lymp J, Afessa B, Hubmayr RD (2004) Ventilator-associated lung injury in patients without acute lung injury at the onset of mechanical ventilation. Crit Care Med 32:1817–1824Google Scholar
- 10.Esteban A, Anzueto A, Frutos F, Alia I, Brochard L, Stewart TE, Benito S, Epstein SK, Apezteguia C, Nightingale P, Arroliga AC, Tobin MJ (2002) Characteristics and outcomes in adult patients receiving mechanical ventilation: a 28-day international study. JAMA 287:345–355Google Scholar
- 11.Bernard GR, Artigas A, Brigham KL, Carlet J, Falke K, Hudson L, Lamy M, Legall JR, Morris A, Spragg R (1994) The American-European Consensus Conference on ARDS. Definitions, mechanisms, relevant outcomes, and clinical trial coordination. Am J Respir Crit Care Med 149:818–824Google Scholar
- 12.Rubenfeld GD, Caldwell E, Granton J, Hudson LD, Matthay MA (1999) Interobserver variability in applying a radiographic definition for ARDS. Chest 116:1347–1353Google Scholar
- 13.The National Heart, Lung, and Blood Institute ARDS Clinical Trials Network (2004) Higher versus lower positive end-expiratory pressures in patients with the acute respiratory distress syndrome. N Engl J Med 351:327–336Google Scholar
- 14.Gajic O, Mendez JC, Rickman OB, Lymp JF, Hubmayr RD, Moore SB (2004) Acute lung injury after blood transfusion in mechanically ventilated patients. Transfusion 44:1468–1474Google Scholar
- 15.McClintock DE, Matthay MA (2004) Why does acute lung injury have no impact on mortality in patients with major trauma? Crit Care Med 32:583–584Google Scholar