1 Department of Anesthesiology, University of Vermont Larner College of Medicine, Burlington, Vermont, john.klick@uvmhealth.org.
2 Rocky Mountain Regional Veterans Affairs Center, Denver, Colorado, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado, Medical Corps, United States Army, Washington, District of Columbia.
3 Departments of Anesthesiology, Orthopaedics and Rehabilitation (by courtesy), and Surgery (by courtesy), University of Vermont Larner College of Medicine, Burlington, Vermont.