Frank Lee, David E. Jamison^*, Robert W. Hurley^†, and Steven P. Cohen^‡*

Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, USA.

^*Department of Anesthesiology, Walter Reed National Military Medical Center, Bethesda, USA.

^†Department of Anesthesiology, Neurology, Psychiatry & Orthopaedics and Rehabilitation, University of Florida, Gainesville, USA.

^‡Department of Anesthesiology and Critical Care Medicine and Physical Medicine & Rehabilitation, Johns Hopkins School of Medicine, and Walter Reed National Military Medical Center, Baltimore, USA.

Correspondence to: Steven P. Cohen. Department of Anesthesiology and Critical Care Medicine and Physical Medicine & Rehabilitation, Johns Hopkins School of Medicine, and Walter Reed National Military Medical Center, 550 North Broadway, Suite 301, Baltimore, MD 21029, USA. Tel: +1-410-955-1818, Fax: +1-410-502-6730, scohen40@jhmi.edu

Received: November 20, 2013; Accepted: November 25, 2013

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