1. Division of Pulmonary, Critical Care and Sleep Medicine, Health Science Center, Texas A&M University, College Station, TX, USA
2. Pulmonary Associates of Corpus Christi, Corpus Christi, TX, USA
3. Critical Care, University of Missouri–Kansas City, Kansas City, MO, USA
4. North Mississippi Health System, Tupelo, MS, USA
5. The University of Texas Health Science Center at Houston, Houston, TX, USA
6. Corpus Christi Medical Center–Bay Area, Corpus Christi, TX, USA