Aaron B Dahl1, Joseph M Neal2, Michael F Mulroy3. 1. Department of Anesthesiology, Virginia Mason Medical Center,Seattle, WA. Electronic address: Aaron.Dahl@virginiamason.org. 2. Department of Anesthesiology, Virginia Mason Medical Center,Seattle, WA. Electronic address: Joseph.Neal@virginiamason.org. 3. Department of Anesthesiology, Virginia Mason Medical Center,Seattle, WA. Electronic address: michael_mulroy_1@msn.com.