[1] Univ Toronto, Dept Surg, Toronto, ON, Canada
[2] Sunnybrook Hlth Sci Ctr, Div Surg Oncol, Odette Canc Ctr, Toronto, ON, Canada
[3] Sunnybrook Res Inst, Clin Evaluat Sci, Toronto, ON, Canada
[4] ICES, Toronto, ON, Canada
[5] Univ Toronto, Dalla Lana Sch Publ Hlth, Div Biostat, Toronto, ON, Canada
[6] Sunnybrook Hlth Sci Ctr, Dept Anesthesiol, Toronto, ON, Canada
[7] Univ Toronto, Dept Anesthesiol & Pain Med, Toronto, ON, Canada
[8] Univ Montreal, Dept Anesthesiol & Pain Med, Montreal, PQ, Canada
[9] Univ Laval, Div Crit Care Med, Dept Anesthesiol & Crit Care Med, Quebec City, PQ, Canada
[10] Univ Laval, Populat Hlth & Optimal Hlth Practices Res Unit, CHU Quebec Univ Laval Res Ctr, Trauma Emergency Crit Care Med, Quebec City, PQ, Canada
[11] Univ Ottawa, Ottawa Hosp, Dept Anesthesiol, Ottawa, ON, Canada
[12] Univ Ottawa, Ottawa Hosp, Dept Pain Med, Ottawa, ON, Canada
[13] Univ Hlth Network, Toronto Western Hosp, Dept Anesthesiol, Toronto, ON, Canada
[14] Univ Hlth Network, TorontoWestern Hosp, Wilson Ctr, Toronto, ON, Canada
[15] Womens Coll Hosp, Womens Coll Res Inst, Toronto, ON, Canada
[16] Univ British Columbia, Dept Anesthesiol Pharmacol & Therapeut, Vancouver, BC, Canada
[17] Univ Manitoba, Sect Thorac Surg, Dept Surg, Winnipeg, MB, Canada
[18] Univ Manitoba, Dept Community Hlth Sci, Winnipeg, MB, Canada
[19] St Pauls Hosp, Providence Hlth Care, Dept Anesthesiol, Vancouver, BC, Canada
[20] Sunnybrook Hlth Sci Ctr, 2075 Bayview Ave, Toronto, ON M4N3M5, Canada