Background Estimates for the incidence of difficult intubation in the obstetric population vary widely, though prior studies reporting rates of difficult intubation in obstetrics are older and limited by smaller samples. The goals of this study were to provide a contemporary estimate of the frequency of difficult and failed intubation in women undergoing general anesthesia for cesarean delivery and to elucidate risk factors for difficult intubation in women undergoing general anesthesia for cesarean delivery. Methods This is a multicenter, retrospective cohort study utilizing the Multicenter Perioperative Outcomes Group database. The study population included women aged 15-44 undergoing general anesthesia for cesarean delivery between 2004 and 2019 at one of 45 medical centers. Co-primary outcomes included the frequencies of difficult and failed intubation. Difficult intubation was defined as Cormack-Lehane view ≥3, intubation attempts ≥3, rescue fiberoptic intubation, rescue supraglottic airway, or surgical airway. Failed intubation was defined as any attempt at intubation without successful endotracheal tube placement. Rates of difficult and failed intubation were assessed. Several patient demographic, anatomical, and obstetric factors were evaluated for potential associations with difficult intubation. Results We identified 14,748 cases of cesarean delivery performed under general anesthesia. There were 295 cases of difficult intubation, with a frequency of 1:49 (95% CI: 1:55, 1:44) (n=14,531). There were 18 cases of failed intubation, with a frequency of 1:808 (95% CI: 1:1,276, 1:511) (n=14,537). Factors with the highest point estimates for the odds of difficult intubation included increased body mass index, Mallampati score III or IV, small hyoid to mentum distance, limited jaw protrusion, limited mouth opening, and cervical spine limitations. Conclusions In this large, multi-center, contemporary study of over 14,000 general anesthetics for cesarean delivery, we observed an overall risk of difficult intubation of 1:49 and a risk of failed intubation of 1:808. Most risk factors for difficult intubation were non-obstetric in nature. These data demonstrate that difficult intubation in obstetrics remains an ongoing concern.

BlueLink is a digital multimedia resource which provides high quality, expert‐reviewed anatomical resources free for educational use and accessible via the web. The BlueLink website was assessed by survey for user demographics and preference data. Data from the survey indicate consumers outside of U‐M are primarily learners from other medical institutions (85.6%). The majority of users came to the site via teacher or peer recommendation (58.4%), or an online search (40.7%), and most use the site for personal study purposes (91.8%). The preferred resources were 1) Online Practice Questions, 2) QuizLink Interactive Quizzes, and 3) BlueLink Cadaveric Atlas Images. Users suggest a potential benefit from making the site easier‐to‐navigate. These results indicate that while BlueLink has an international student user base, it can still expand to provide more of the requested video and animation‐based resources for its diverse variety of anatomical learners. These results demonstrate that digital resources, specifically cadaveric and quiz‐based, are highly utilized and preferred by anatomy students.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.