ASA Updates Difficult Airway Guidelines

For the first time in nearly a decade, the American Society of Anesthesiologists (ASA) has updated its existing practice guidelines for difficult airway management. Last revised in 2012, and published in 2013, the new guidelines include a host of important modifications that reflect changing practice patterns in the field. The 2022 American Society of Anesthesiologists Practice Guidelines for Management of the Difficult Airway were published online on Nov. 11 in Anesthesiology.

“On Oct. 13, the ASA House of Delegates approved the 2022 update of the ASA’s practice guidelines for the management of the difficult airway,” said William H. Rosenblatt, MD, a co-author of the guidelines. “The 15-member task force producing this update—led by Drs. Jeffrey Apfelbaum, Carin Hagberg and Rick Connis—included methodologists; intensivists; physicians in private practice, pediatric anesthesia practice, administrative roles and content experts; and leaders of societies focused on airway management.”

The new guidelines are the society’s first to be developed by an international task force of anesthesiologists, comprising professionals from a variety of anesthesiology, airway and other medical organizations. They offer evidence from a wide range of new research, as well as findings from surveys of expert consultants, ASA members and 10 participating organizations, both domestic and international.

“The task force met for the first time in August 2019 to develop an evidence model that was used to guide a search of the relevant literature,” explained Rosenblatt, a professor of anesthesiology at Yale School of Medicine, in New Haven, Conn. “Over the next year, the task force's methodologists examined more than 10,000 abstracts, whittling this body of literature down to 367 papers that were acceptable as evidence.”

Scope of the Guidelines Has Been Expanded

Specifically, the guidelines focus on management of difficult airways—whether anticipated or unanticipated—that may be encountered during a variety of procedures, including mask ventilation, tracheal intubation or supraglottic airway placement. The document is unique from its predecessors in that its scope has been expanded to include pediatric patients, non-OR procedures (including within the ICU), and sedation, regional anesthesia and obstetrics cases.

Although the stated purpose of the guidelines is to “guide the management of patients with difficult airways, optimize first-attempt success of airway management, improve patient safety during airway management, and minimize/avoid adverse events,” Rosenblatt said they are ultimately intended to offer clinicians a solid practical foundation, from which an individual practitioner can improve care.

“The purpose of the guidelines has previously been an emphasis on safe airway management,” he said. “This has been extended to optimizing success of the first attempt at airway management, along with a recognition that the appropriate choice of management devices and techniques is dependent on the experience, training and preferences of the airway operator, and will be influenced by medical issues and the context in which airway management takes place.

“And while guidelines provide recommendations that are intended to improve decision making,” he added, “they also depend upon the judgment of the responsible anesthesiologist and the practice in the local community. Interpretation and implementation of the guidelines takes place within the context of a local institution, and departures are often appropriate from these guidelines.”

Table. Modifications Found in the New ASA Difficult Airway Guidelines ASA, American Society of Anesthesiologists

Updated equipment for standard and advanced difficult airway management

New recommendations for supplemental oxygen administration before initiating and throughout difficult airway management, including the extubation process

Recommendations regarding invasive and noninvasive alternatives for difficult airway management

An emphasis on staying aware of the passage of time and limits regarding the number of attempts with different devices and techniques during difficult airway management

More robust recommendations for extubation of the difficult airway

New algorithms and infographics for difficult airway management in both adults and children

Nevertheless, there are several fundamental modifications to the document that most clinicians will find notable (Table). Two innovations proved particularly intriguing to Rosenblatt: recommendations for extubation, and the development of new algorithms and infographics for difficult airway management.

“The ASA Difficult Airway Algorithm has been a major achievement of the task force since its inception and first publication in 1993,” he said. “Over subsequent iterations there have been changes in this algorithm that have improved its utility, including the addition of supraglottic airway rescue and video laryngoscopy.”

The new algorithm emphasizes interindividual differences between the professionals making clinical decisions, including factors such as clinician experience, available resources and clinical context. The algorithm also stresses early calls for help, the confirmation of gas exchange by the detection of carbon dioxide (independent of the device being used) and limits on the number of attempts at laryngoscopy.

A novel decision tree also has been appended to the 2022 version of the algorithm. “The decision tree may help anesthesiologists consider factors that might drive them towards the awake intubation pathway, which was present in all previous publications,” Rosenblatt said.

Also New: Infographics

Finally, the new guidelines have added novel infographics for pediatric and adult airway management following the induction of anesthesia. The product of substantial efforts by the task force, the infographics meld evidence-based recommendations with expert opinion, and are meant to emphasize flexibility and the interindividual variation that occurs during airway management.

“As with the algorithm itself, the infographics include both nonemergency and emergency pathways, and are distinguished by the measurement of CO₂ assessed after each management attempt,” Rosenblatt said. “They emphasize the preferences of the primary manager, the use of capnography to judge the adequacy of gas exchange, limitations on the number of attempts at management, and awareness of oxygen saturation and the passage of time.”

Novel, flexible and founded on the most recent evidence in the field, the ASA’s new difficult airway management guidelines are a testament to the society’s commitment to enhancing anesthesiology practice, regardless of the clinical scenario.

“Historically, the guidelines are the most downloaded document that Anesthesiology publishes,” Rosenblatt concluded. “So, it’s a pretty big deal.”

—Michael Vlessides

Rosenblatt reported no relevant financial disclosures.