Felipe Urdaneta, MD
Secretary, Society for Airway Management
Professor of Anesthesiology
University of Florida
North Florida/South Georgia Veterans Health System
Gainesville, Florida
Lauren Berkow, MD
Vice President, Society for Airway Management
Associate Professor
University of Florida College of Medicine
Gainesville, Florida
In the last 30 years, new technology has revolutionized difficult airway management. The introduction of the supraglottic airway (SGA) in the early 1980s provided a method to oxygenate and ventilate patients after failed mask ventilation, affording us a solution when difficult intubation was encountered, therefore making difficult airway management much safer.
Some years later, SGA devices were incorporated into the 2003 American Society of Anesthesiologists (ASA) Difficult Airway Algorithm, both as rescue devices and as conduits for intubation.1 The addition of SGA devices to our airway management armamentarium also marked a period of interest in developing newer technologies and/or improving existing ones. The result has been innovations in airway management that have exploded over the past 10 years, resulting in many new airway devices that we suspect will have a similar revolutionary effect on airway management and decision making as the laryngeal mask airway did in the later stages of the 20th century.
We owe a debt of gratitude to innovators and visionaries such as Jack Pacey, MD, and Marshall Kaplan, MD, who in early 2000 introduced us to video laryngoscope devices. Dr Kaplan led a team that developed a video laryngoscope with a micro-video module device, and Dr Pacey developed the first true commercial complementary metal-oxide semiconductor video laryngoscope, and we have never looked back. These alternative methods of laryngoscopy and tracheal tube placement are considered truly revolutionary.
Video Laryngoscopy as Standard of Care?
Video laryngoscopy (VL) may and perhaps should replace direct laryngoscopy as a first-line intubation method. Video laryngoscope devices allow airway providers to “see around the corner” and improve laryngeal exposure as well as increase first-attempt intubation rates, especially by novice personnel, and are changing how we teach laryngoscopy by allowing instructors to see what trainees see.
As with any new invention or device, there are also some concerns about less positive aspects of its use: Delivery of the endotracheal tube through the glottic opening is not always easy or possible in some patients, and prevention and avoidance of desaturation are still major issues, especially in critically ill patients.2 There are also concerns about safety, cost, and limited availability in every location and for every patient.
As with any other airway device(s), training and familiarity are essential for successful use, and cross performance (success with one device or type of device/blade compared with a similar class of device) is not always associated with the same success.
Whether VL will become the standard of care for intubation remains to be seen; the ASA, Difficult Airway Society, and Canadian guidelines for airway management all discuss the use and advantages of VL over direct laryngoscopy, but we currently have limited information whether VL should be for first-line use or reserved as a rescue option when first-line methods have failed.3-6 There is also not enough evidence to recommend one device, manufacturer, or blade design over others, and whether channeled or unchanneled devices are more beneficial in certain circumstances.7
Another interesting aspect associated with the proliferation and widespread availability and use of video laryngoscopes is how personnel in training are able to complete the learning curves for many products and devices we have at our disposal.
More importantly, we should ask ourselves: What is the current, evolving role of flexible fiber-optic endoscopes for intubation? There is a paucity of data, but widespread observation points to a decrease in use and familiarity with flexible endoscopy among current trainees, and this is of serious concern.8,9
As discussed, VL affords better glottic exposure in most patients; however, this might not be the case in patients with anatomic airway distortion. Therefore, we must continue to expose and train current generations about endoscopic airway assessment and intubation.10
The greater success rates of intubation also have allowed us to focus our attention on old issues such as decision making, the creation of backup plans, and aspiration of gastric contents, as reported in NAP4 (4th National Audit Project).11 In this special edition of Anesthesiology News, for example, a novel mechanical trainer for aspiration is discussed; we are certain that this trainer will revolutionize the way newer generations are trained to deal with this problem and not just focus on prevention, as perhaps our generation did.
One of the most interesting and novel concepts of the last few years is the resurgence of the use of passive oxygenation and the emergence of newer technologies. For years, we relied on the concept of preoxygenation as a method to prevent desaturation during periods of apnea and during airway management. As our population has become sicker and obesity has reached epidemic proportions, prevention of desaturation and maintenance of oxygenation during airway management has taken a pivotal role in airway management.12,13
Maintaining adequate oxygenation and ventilation are the key aspects of airway management, and patients suffer harm from lack of oxygenation and ventilation, not lack of intubation. The use of passive nasal oxygenation via a high-flow nasal cannula has been shown to be effective in preventing desaturation during airway management, especially during emergency airway situations.14 A recent study by Patel and Nouraei reported apnea times as long as 14 minutes without desaturations below 90% with the Optiflow (Fisher & Paykel), a device that provides humidified high-flow nasal oxygen with continuous positive airway pressure.15
Another device, the SuperNO2VA Device (Revolutionary Medical Devices), also is available and provides positive-pressure ventilation via a nasal mask.16 We are certain that more information will be available in the coming years and we will be able to elucidate which methods are optimal for oxygen supply and flow, as well as which patients will benefit the most from these passive methods of oxygen administration.
Conclusion
There is no question that emerging and evolving technologies have significantly changed the approach to difficult airway management, as well as the approach to airway education and training. We are privileged to live in the midst of such an explosive period of growth in airway technologies that, undoubtedly, will make airway management less unpredictable, safer, and hopefully less stressful for both patients and providers.
References
- American Society of Anesthesiologists Task Force on Management of the Difficult Airway. 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. 2003;98(5):1269-1277.
- Mosier JM, Joshi R, Hypes C, et al. The physiologically difficult airway.West J Emerg Med. 2015;16(7):1109-1117.
- Apfelbaum JL, Hagberg CA, Caplan RA, et al. 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. 2013;118(2):251-270.
- Frerk C, Mitchell VS, McNarry AF, et al. Difficult Airway Society 2015 guidelines for management of unanticipated difficult intubation in adults.Br J Anaesth. 2015;115(6):827-848.
- Law JA, Broemling N, Cooper RM, et al. The difficult airway with recommendations for management—part 2: the anticipated difficult airway.Can J Anaesth. 2013;60(11):1119-1138.
- Rothfield KP, Russo SG. Videolaryngoscopy: should it replace direct laryngoscopy? A pro-con debate.J Clin Anesth. 2012;24(7):593-597.
- Norris A, Heidegger T. Limitations of videolaryngoscopy.Br J Anaesth. 2016 Jun 1. [Epub ahead of print]
- Ahmad I, Bailey CR. Time to abandon awake fibreoptic intubation? 2016;71(1):12-16.
- Ward P. Training in fibreoptic intubation – I. 2016;71(5):593.
- Law JA, Broemling N, Cooper RM, et al. The difficult airway with recommendations for management—part 1—difficult tracheal intubation encountered in an unconscious/induced patient.Can J Anaesth. 2013;60(11):1089-1118.
- Woodall N, Frerk C, Cook TM. Can we make airway management (even) safer? Lessons from national audit. 2011;66(suppl2):27-33.
- Mort TC. Complications of emergency tracheal intubation: immediate airway-related consequences: part II.J Intensive Care Med. 2007;22(4):208-215.
- De Jong A, Fuller E, Millot A, et al. How to preoxygenate in the operating room: healthy subjects and situations “at risk.”Ann Fr Anesth Reanim. 2014;33(7-8):457-461.
- Weingart SD, Levitan Preoxygenation and prevention of desaturation during emergency airway management.Ann Emerg Med. 2012;59(3):165-175.e1.
- Patel A, Nouraei SA. Transnasal Humidified Rapid-Insufflation Ventilator Exchange (THRIVE): a physiological method of increasing apnoea time in patients with difficult airways. 2015;70(3):323-329.
Leave a Reply
You must be logged in to post a comment.