aDepartment of Anesthesiology and Perioperative Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York

bDepartment of Anesthesiology, Pain and Perioperative Medicine, The George Washington University School of Medicine, Children's National Hospital, Washington, District of Columbia, USA

Correspondence to Audra M. Webber, MD, FASA, Department of Anesthesiology and Perioperative Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Box 604, Rochester, NY 14642, USA. Tel: +1 585 276 7881; e-mail: [email protected]