Foundations of Risk Assessment era
In the Foundations of Risk Assessment era (1949–1978), representative authors such as Saklad formalized preoperative risk stratification by introducing the ASA physical status classification system. This standardized framework grew from and alongside large-scale observational data that linked patient status to perioperative morbidity and mortality, providing empirical anchors for risk evaluation. Pioneers in recovery measurement also contributed, with the Ramsay sedation and postoperative recovery efforts integrating analgesia, regional techniques, and safety monitoring to tie clinical recovery endpoints to patient safety. Together, these authors and measurement initiatives established the conceptual scaffolding for later formal perioperative risk frameworks by connecting standardized classifications, recovery endpoints, and anesthesia practices to predict outcomes.
Evidence-Based Standardization era
Salim Yusuf [1] is a leading figure in perioperative medicine during the Evidence-Based Standardization era, with affiliations spanning McGill University and Génome Québec Innovation Centre [3] and Harvard University [4]. His era-defining contribution comes from the POISE trial, Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery (POISE trial): a randomised controlled trial [7], which influenced perioperative beta-blockade strategies and the move toward risk-adjusted, standardized decisions in anesthesia and surgery. Kate Leslie [2] is a pivotal perioperative medicine scholar with ties to University of California, San Francisco [5] and University of Toronto [6] during this period. Her work on the POISE trial paper as co-author [7] helped embed evidence-based standardization by providing robust randomized data that guided risk-stratified practice changes across cardiology, anesthesia, and surgery. Data-Driven Perioperative Care era
Henrik Kehlet, the progenitor of Enhanced Recovery After Surgery (ERAS), championed standardized perioperative pathways incorporating multimodal analgesia, early feeding and mobilization to reduce complications and shorten hospital stays. Atul Gawande clarified the role of checklists and quality-improvement methods in surgery, translating data into scalable safety practices and guidelines that mitigate perioperative risk. Kenneth Inouye's delirium prevention research, including the development of the CAM and perioperative cognitive-protection guidelines, integrated cognitive risk into data-guided anesthesia and recovery programs. Paul Myles has championed trial-based targets for fluid and hemodynamic management within ERAS, promoting goal-directed therapy as a core component of data-driven perioperative care.