September 1, 2013
Volume 77, Number 9
Educating Physician Anesthesiologists to Better Manage Patients With a Difficult Airway
P. Allan Klock, Jr., M.D.
Maintaining patient oxygenation and ventilation are among the highest priority tasks for a physician anesthesiologist. During the past 20 years, because the prevalence of severe obesity and obstructive sleep apnea have more than doubled in the United States, a large proportion of our patients are at risk for difficult laryngoscopy, difficult ventilation or aspiration of gastric contents. During the same time period, supraglottic airways and video-assisted airway devices have been introduced and now assume a prominent place in the ASA Difficult Airway Algorithm.1,2 Studies using large databases have been published that offer insight into the risk factors for a difficult airway, modes of injury and clinicians’ responses to challenging airway situations.3,4 The confluence of these events gives physician anesthesiologists opportunities to improve care but also demands that we revise training curricula and re-educate ourselves to assimilate new technologies, techniques and information into our care models.
Three essential elements are needed for successful airway management: knowledge, judgment and manual skills. The physician anesthesiologist must have the knowledge that new technologies or techniques exist and understand the indications and contraindications for their use. The airway manager must have judgment to be able to formulate an appropriate airway management strategy. For example, it takes judgment to decide that a patient’s airway should be secured while the patient is awake rather than after induction of anesthesia. Finally, without the skill to use a device properly or execute a technique, the physician anesthesiologist may not be successful despite developing a good plan for airway management. An appropriate airway educational program should enhance knowledge, improve judgment and increase skills. Physician anesthesiologists who have completed their training will need a strategy to ensure they are up to date with respect to advances in airway management, and that their judgment and skills are sufficient to provide safe patient care.
Airway management is a high-tempo, high-risk activity. When a patient is rendered unconscious, missteps in airway management can quickly lead to permanent serious injury or death. In training programs there is a constant tension between fulfilling the educational mission and providing optimal patient care. In many training situations there are few consequences when a junior trainee tries a procedure under appropriate supervision. In airway management, often the first attempt affords the best conditions and the lowest risk. The potential consequences of a failed first attempt, however, include dental damage, soft tissue injury, bleeding, edema and aspiration of gastric contents.
In some settings, rapid-sequence induction of general anesthesia, neuromuscular blockade and intubation of the trachea is the best option. Then, it may be best to have the most experienced laryngoscopist secure the airway rather than allow a trainee to have the first try. The decision of who will be at the head of the bed should be made by the most senior physician anesthesiologist present and takes into account the skill of the trainee, the risk of aspiration of gastric contents, or of difficult laryngoscopy, intubation or ventilation if intubation is initially unsuccessful. If the plan is to secure the airway before induction of anesthesia, time pressure and risk of complications are reduced, which places the junior trainee in a favorable position. In teaching institutions there are competing interests when a patient requires airway management in the intensive care unit, emergency department or other areas outside the operating room. It is best to have agreed-upon protocols between the anesthesia department and other departments with trainees who seek airway management experience. In the absence of these protocols, if a physician anesthesiologist has been requested to help manage a patient’s airway, they decide which trainee (if any) is given the first chance to manage the airway.
The introduction of video technology has had a positive impact on airway management training. Video technology is used with flexible bronchoscopes, intubating stylets and a variety of laryngoscopes. When a video image is displayed, the conditions for the trainee improve in several ways. The attending physician anesthesiologist and others in the room tend to be more patient. Staff are able to assist the trainee with maneuvers such as applying traction to the tongue, initiating jaw thrust and suctioning the airway. Finally, the supervising physician anesthesiologist is able to direct the trainee with specific instructions and an explanation of the displayed anatomy.
Highly angled video laryngoscopes (VLs) have led to a paradigm shift in airway management. With direct laryngoscopy (DL), a straight, uninterrupted line is created from the operator’s eye to the larynx. Once this line has been established, delivering the tube through the vocal cords is relatively easy. With highly angled VLs, visualizing the glottis is easier, but because the straight line of sight is not established, the special techniques for delivering the tube through the vocal cords have frustrated some practitioners skilled in DL but not in VL intubation. The distinction between difficult laryngoscopy and difficult intubation is reflected in the most recent ASA Difficult Airway Algorithm.
How should physician anesthesiologists respond to the changing landscape of airway management? First, keep up to date with the “knowledge-judgment-skill” triad. To maintain a high level of manual skill, use a spectrum of airway tools such as flexible bronchoscopes, second-generation and intubating supraglottic airways, and a variety of videolaryngoscopes regularly. Airway trainers, simulators and animal specimens such as pig tracheas can be used to practice invasive techniques suited only for an emergency such as percutaneous or surgical cricothyrotomy. To maintain current knowledge, keep abreast of advances in airway management by reading the relevant literature and participating in CME activities that cover airway management. Judgment, based largely on sound medical principles, is enhanced with clinical experience, participation in morbidity and mortality or quality improvement conferences, and consultation with colleagues. Participation in airway courses (information for many can be found online) and airway lectures and workshops at meetings, including the annual meetings of the ASA and the Society for Airway Management, strengthens all parts of the knowledge-judgment-skill triad. Many attendees find discussion with course faculty a very helpful adjunct to formal workshop and lecture offerings.
Our promise to safely manage an unconscious patient’s airway is a sacred trust. As physician anesthesiologists, we owe it to our patients to bring current knowledge, sound judgment and competent skills to the clinical arena every day.
P. Allan Klock, Jr., M.D. is Professor, Vice Chair for Clinical Affairs, and President of the Medical Staff, University of Chicago, Department of Anesthesia and Critical Care, Chicago, Illinois.
1.Caplan R, Benumof JL, Berry FA, Blitt CA, Bode RH, Cheney FW, Connis RT, Guidry OR, Ovassapian A. Practice guidelines for management of the difficult airway: A report by the ASA Task Force on Management of the Difficult Airway. Anesthesiology 1993; 78:597-602
2.Apfelbaum JL, Hagberg CA, Caplan RA, Blitt CD, Connis, RT, Nickinovich, DG, Ovassapian A. Practice guidelines for management of the difficult airway: an updated report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway. Anesthesiology 2013; 118(2): 251-270
3.Kheterpal S, Martin L, Shanks AM, Tremper KK. Prediction and outcomes of impossible mask ventilation: a review of 50,000 anesthetics. Anesthesiology 2009; 110(4): 891-897
4.Cook TM, Woodall N, Frerk CO. Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society. Part 1: anaesthesia. Br J Anaesth 2011; 106(5):617-631
Disclosures: Dr. Klock is a past-president of the Society for Airway Management and serves as an unpaid member of the Scientific Advisory Board for Ambu Corporation.
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