[1] San Antonio Uniformed Serv Hlth Educ Consortium, Pulm & Crit Care, San Antonio, TX 78229 USA
[2] Brooke Army Med Ctr, Internal Med, Ft Sam Houston, TX 78234 USA
[3] Madigan Army Med Ctr, Internal Med, Joint Base Lewis Mccord, WA USA
[4] Walter Reed Natl Mil Med Ctr, Pulm & Crit Care, Bethesda, MD USA
[5] Brooke Army Med Ctr, Pulm & Crit Care, Ft Sam Houston, TX 78234 USA