1. Anesthesia, Pain Management and Perioperative Medicine, Psychiatry and Pharmacology, Dalhousie University, Halifax, Nova Scotia, Canada
2. Department of Clinical Neurological Sciences, Western University, London, Ontario, Canada
3. Department of Anesthesia and Perioperative Medicine, Western University, London, Ontario, Canada
4. Department of Anesthesia, Alan Edwards Pain Management Unit, McGill University Health Centre (MUHC), Montreal, Quebec, Canada