[1] Guizhou Prov Peoples Hosp, Dept Resp & Crit Care Med, Guiyang, Guizhou, Peoples R China
[2] Mayo Clin, Dept Anesthesiol & Perioperat Med, Rochester, MN 55905 USA
[3] Xian Med Univ, Affiliated Hosp 1, Dept Resp & Crit Care Med, Xian, Shaanxi, Peoples R China
[4] Mayo Clin, Dept Physiol & Biomed Engn, Rochester, MN 55905 USA