- Journal club critique
- Open Access
Higher initial tidal volumes associated with the subsequent development of acute lung injury in dose-response relationship
© BioMed Central Ltd 2005
- Published: 20 October 2005
Gajic O, Dara SI, Mendez JL, Adesanya AO, Festic E, Caples SM, Rana R, St Sauver JL, Lymp JF, Afessa B, Hubmayr RD: Ventilator-associated lung injury in patients without acute lung injury at the onset of mechanical ventilation. Crit Care Med 2004, 32:1817–1824 .
Although ventilation with small tidal volumes is recommended in patients with established acute lung injury, most others receive highly variable tidal volume aimed in part at normalizing arterial blood gas values. We tested the hypothesis that acute lung injury, which develops after the initiation of mechanical ventilation, is associated with known risk factors for ventilator-induced lung injury such as ventilation with large tidal volume.
Retrospective cohort study.
Four intensive care units in a tertiary referral center.
332 patients who received invasive mechanical ventilation for ≥48 hrs between January and December 2001.
The main outcome of interest, acute lung injury, was assessed by independent review of daily digital chest radiographs and arterial blood gases. Ventilator settings, hemodynamics, and acute lung injury risk factors were extracted from the Acute Physiology and Chronic Health Evaluation III database and the patients' medical records.
Of 332 patients who did not have acute lung injury from the outset, 80 patients (24%) developed acute lung injury within the first 5 days of mechanical ventilation. When expressed per predicted body weight, women were ventilated with larger tidal volume than men (mean 11.4 vs. 10.4 ml/kg predicted body weight, p < 0.001) and tended to develop acute lung injury more often (29% vs. 20%, p = 0.068). In a multivariate analysis, the main risk factors associated with the development of acute lung injury were the use of large tidal volume (odds ratio 1.3 for each ml above 6 ml/kg predicted body weight, p < 0.001), transfusion of blood products (odds ratio, 3.0; p < 0.001), acidemia (pH < 7.35; odds ratio, 2.0; p = 0.032) and a history of restrictive lung disease (odds ratio, 3.6; p = 0.044).
The association between the initial tidal volume and the development of acute lung injury suggests that ventilator-associated lung injury may be an important cause of this syndrome. Height and gender should be considered when setting up the ventilator. Strong consideration should be given to limiting large tidal volume, not only in patients with established acute lung injury but also in patients at risk for acute lung injury.
Based on the results of this study and the earlier work by Lee and colleagues , a prospective randomized and (ideally) multicentric trial of low tidal volume ventilation in patients without ALI is warranted. Such a trial should address the safe lower tidal volume limit and the role of PEEP in low tidal volume strategies. Until data from a well-designed trial are available, we cannot recommend universal application of this strategy.
- Gajic O, Dara SI, Mendez JL, Adesanya AO, Festic E, Caples SM, Rana R, St Sauver JL, Lymp JF, Afessa B, Hubmayr RD: Ventilator-associated lung injury in patients without acute lung injury at the onset of mechanical ventilation. Crit Care Med 2004, 32: 1817-1824. 10.1097/01.CCM.0000133019.52531.30View ArticlePubMedGoogle Scholar
- Dreyfuss D, Saumon G: Ventilator-induced lung injury: lessons from experimental studies. Am J Respir Crit Care Med 1998, 157: 294-323.View ArticlePubMedGoogle Scholar
- Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. The Acute Respiratory Distress Syndrome Network N Engl J Med 2000, 342: 1301-1308. 10.1056/NEJM200005043421801Google Scholar
- Lee PC, Helsmoortel CM, Cohn SM, Fink MP: Are low tidal volumes safe? Chest 1990, 97: 430-434.View ArticlePubMedGoogle Scholar
- Dreyfuss D: Acute lung injury and mechanical ventilation: need for quality assurance. Crit Care Med 2004, 32: 1960-1961. 10.1097/01.CCM.0000139619.27651.86View ArticlePubMedGoogle Scholar