13 Variables That Predict Difficult MV

Background: Anesthetic agents can compromise the airway and the ability to provide mask ventilation (MV) is a critical skill that all practitioners providing anesthesia must have. Objective: To assess risk factors in predicting difficult MV in nonobstetric adult patients aged ≥18 years managed in the operating room. Design: Systematic review and meta-analysis of observational studies. Methods: Airway- or patient-related risk factors for difficult MV reported in >20% of eligible studies identified through literature review. Results: Data from 335,846 patients from 20 (prospective, 15 and retrospective, 5) studies published between 2005 and 2022 were analyzed. Study sizes varied from 90 to 176,679 patients. Difficult MV ranged from 0.4% to 38.9%. Pooled data from 16 and 4 studies that assessed the general population and patients with obesity reported an incidence of 6.1% and 14.4%, respectively. Each of the parameters identified below were assessed in several studies (5 to 17) with more...