1 Department of Pulmonary & Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, OH, USA. Electronic address: bhardwa3@ccf.org.
2 Department of Internal Medicine, Cleveland Clinic Fairview Hospital, Cleveland, OH, USA.
3 Department of Pulmonary & Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, OH, USA; Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA.
4 Department of Emergency Medicine and Center for Resuscitation Science, University of Pennsylvania, Philadelphia, PA, USA.