1. Department of Emergency Medicine, Hospital Universitario HM Sanchinarro, Madrid, Spain
2. Research Foundation HM Hospitales, HM Hospitales, Madrid, Spain
3. Hospital Universitario de Getafe, Madrid, Spain
4. CIBER de Enfermedades Respiratorias, Madrid, Spain
5. Universidad Europea, Madrid, Spain
6. Center for Lung Biology, Division of Pulmonary and Critical Care Center, University of Washington, Seattle, Washington; and
7. Medical Research Service, VA Puget Sound Healthcare System, Seattle, Washington