Rationale and design of the PeriOperative ISchemic Evaluation-2 (POISE-2) trial: An international 2 × 2 factorial randomized controlled trial of acetyl-salicylic acid vs placebo and clonidine vs placebo in patients undergoing noncardiac surgery

BACKGROUND: Worldwide, 200 million adults undergo major noncardiac surgery annually, and 10 million of these patients will have a major vascular complication. Low-dose clonidine and low-dose acetyl-salicylic acid (ASA) may prevent major perioperative vascular complications. We therefore initiated the POISE-2 trial to establish the perioperative effects of these 2 interventions. METHODS: The POISE-2 trial is a 2 × 2 factorial randomized …