Tibor Kristian1,2, Bingren Hu3,4. 1. Department of Anesthesiology, Shock Trauma and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, MD, 21201, USA. tkristian@som.umaryland.edu. 2. Veterans Affairs Maryland Health Center System, 10 North Greene Street, Baltimore, MD, 21201, USA. tkristian@som.umaryland.edu. 3. Department of Anesthesiology, Shock Trauma and Anesthesiology Research Center, University of Maryland School of Medicine, Baltimore, MD, 21201, USA. bhu@som.umaryland.edu. 4. Veterans Affairs Maryland Health Center System, 10 North Greene Street, Baltimore, MD, 21201, USA. bhu@som.umaryland.edu.