BACKGROUND: Identifying a potentially difficult airway is crucial both in anaesthesia in the operating room (OR) and non-operation room sites. There are no guidelines or expert consensus focused on the assessment of the difficult airway before, so this expert consensus is developed to provide guidance for airway assessment, making this process more standardized and accurate to reduce airway-related complications and improve safety. METHODS: Seven members from the Airway Management Group of the Chinese Society of Anaesthesiology (CSA) met to discuss the first draft and then this was sent to 15 international experts for review, comment, and approval. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) is used to determine the level of evidence and grade the strength of recommendations. The recommendations were revised through a three-round Delphi survey from experts. RESULTS: This expert consensus provides a comprehensive approach to airway assessment based on the medical history, physical examination, comprehensive scores, imaging, and new developments including transnasal endoscopy, virtual laryngoscopy, and 3D printing. In addition, this consensus also reviews some new technologies currently under development such as prediction from facial images and voice information with the aim of proposing new research directions for the assessment of difficult airway. CONCLUSIONS: This consensus applies to anesthesiologists, critical care, and emergency physicians refining the preoperative airway assessment and preparing an appropriate intubation strategy for patients with a potentially difficult airway.

Air Methods Corporation Greenwood Park CO USA

Anesthesia and Intensive Care San Martino Policlinico Hospital IRCCS for Oncology and Neuroscience Genoa Italy

Anesthesia and Intensive Care Unit Azienda Ospedaliero Universitaria delle Marche Ancona Italy

Department of Anaesthesia Yong Loo Lin School of Medicine National University of Singapore Singapore Singapore

Department of Anaesthesiology and Intensive Care Medicine University Hospital Hradec Kralove Hradec Kralove Czech Republic

Department of Anaesthesiology Beijing Hospital National Center of Gerontology Institute of Geriatric Medicine Chinese Academy of Medical Science Beijing China

Department of Anaesthesiology National and Kapodistrian University of Athens Athens Greece

Department of Anesthesia Critical Care and Pain Medicine Massachusetts General Hospital Boston MA USA

Department of Anesthesiology Beijing Friendship Hospital Capital Medical University Beijing China

Department of Anesthesiology Peking Union Medical College Hospital Beijing China

Department of Anesthesiology Plastic Surgery Hospital CAMS and PUMC Beijing China

Department of Anesthesiology Shanghai Ninth People's Hospital Shanghai Jiao Tong University School of Medicine Shanghai China

Department of Anesthesiology The 1st Affiliated Hospital of Guangzhou University of Chinese Medicine Guangzhou China

Department of Anesthesiology The University of Hong Kong Hong Kong China

Department of Biomedical Sciences and Public Health Università Politecnica delle Marche Ancona Italy

Department of Conservative Dentistry and Endodontics Jamia Millia Islamia New Delhi India

Division of Anaesthetics Pain Medicine and Intensive Care Department of Surgery and Cancer Faculty of Medicine Imperial College London and Chelsea and Westminster Hospital London UK

Division of Dental Anesthesiology Graduate School of Medicine and Dental Sciences Niigata University Niigata Japan

Division of Emergency Medical Services Logan Health Kalispell MT USA

Institute of Anesthesia and Intensive Care Unit University Hospital of Padua Padua Italy

Lee Kong Chian School of Medicine Nanyang Technological University Singapore Singapore

Paolo Procacci Foundation Roma Italy

Unit of Anaesthesia Intensive Care and Pain Management Department of Medicine Università Campus Bio Medico of Rome Roma Italy

Unit of Anesthesia and Intensive Care Mazzoni Hospital Ascoli Piceno Italy

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