1 Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100730, China.
2 Department of Neurology, Baotou Central Hospital, Baotou, Inner Mongolia 014040, China.
3 Department of Critical Care Medicine, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou 550001, China.