Department of Anesthesiology, Critical Care and Pain Medicine, McGovern Medical School at the University of Texas Health Science Center, Houston, Texas, USA

Correspondence to Omonele Nwokolo, MD, FASA, University of Texas McGovern Medical School: The University of Texas Health Science, Center at Houston John P and Katherine G McGovern Medical School, Houston, TX, USA. Tel: +1 713 500-6750; e-mail: [email protected]