Flowchart procedure inclusion. All procedures identified in the anesthetic information management system, and those included in our analyses. Included procedures were required to be medium- to high-risk procedures between 2011 and 2014 on patients who were 60 yr or older. Procedures should be new (no procedures on the same patient in the previous yr) and have sufficient (at least 15) invasive blood pressure measurements available after time of induction.^{2,3,15–27,30–53}