[1] McGill Univ, Dept Emergency Med, Hlth Ctr, 1001 Decarie Blvd, Montreal, PQ H4A 3J1, Canada
[2] Univ Toronto, Div Emergency Med, 500 Univ Ave Suite 602, Toronto, ON M5G 1V7, Canada
[3] Univ Toronto, Sunnybrook Hlth Sci Ctr, Dept Surg, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada
[4] Univ Toronto, Sunnybrook Hlth Sci Ctr, Interdept Div Crit Care Med, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada
[5] St Michaels Hosp, Div Geriatr Med, 30 Bond St, Toronto, ON M5B 1W8, Canada