1. Critical Care Department, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada,
2. Trauma Program, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
3. University of Texas Southwestern Medical School, Dallas, Texas, USA
4. Trauma Program, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada, Division of General Surgery, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada