MORBID OBESITY AND SLEEP APNEA: Edited by Frances F. ChungAn update on preoperative assessment and preparation of surgical patients with obstructive sleep apneaMadhusudan, Poorna; Wong, Jean; Prasad, Arun; Sadeghian, Elena; Chung, Frances F. Author Information Department of Anaesthesia, Toronto Western Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada Correspondence to Dr Frances F. Chung, MBBS, FRCPC, Professor, Department of Anaesthesia, Toronto Western Hospital, University Health Network, University of Toronto, 399 Bathurst Street, Toronto, ONT M5T 2S8, Canada. Tel: +1 416 603 5118; fax: +1 416 603 6494; e-mail: [email protected] Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website (www.co-anesthesiology.com). Current Opinion in Anaesthesiology: February 2018 - Volume 31 - Issue 1 - p 89-95 doi: 10.1097/ACO.0000000000000539 Buy SDC Metrics Abstract Purpose of review There is a high prevalence of obstructive sleep apnea (OSA) in the surgical population, however, a significant proportion of patients are undiagnosed. The Society of Anesthesia and Sleep Medicine (SASM) has issued recent guidelines for preoperative assessment and preparation of patients with known or suspected OSA. The purpose of this review is to highlight key points in the new guidelines and explore the possibilities of different strategies in optimizing patients with OSA preoperatively. Recent findings Recent knowledge on phenotypes and endotypes has provided a better understanding of the disease and its underlying pathogenesis. Phenotypes refer to the predominant morphological characteristics of an individual whereas endotypes refer to the predominant underlying mechanism of the disease. Phenotypes and endotypes in OSA are heterogenous. Heterogeneity in the pathogenic mechanisms implies that opportunities other than the use of continuous positive airway pressure (CPAP) may exist to optimize or manage OSA patients preoperatively. Summary The prevalence of OSA in surgical patients is high. SASM has made recommendations in their published guidelines for the optimum preoperative preparation of patients with OSA. In the future, research may shift towards finding the underlying mechanism of OSA for targeted therapy. Copyright © 2018 YEAR Wolters Kluwer Health, Inc. All rights reserved.