Kamen Vlassakov, MD
Director, Regional & Orthopedic Anesthesia
Brigham and Women’s Hospital
Harvard Medical School
Dr Vlassakov reported no relevant financial disclosures.
Multimodal airway approaches are being designed as a response to unusual difficult airway cases. Perhaps it is time to consider including these approaches in difficult airway algorithms as a final step before resorting to surgical access.
Huge technological advances, an overwhelming plethora of devices with competitive costs, and their increased availability around the world have all enhanced the ability to manage the difficult airway, but have not eliminated the risk for failure. In fact, at times the gains seem modest compared with the effort and cost. Increased acuity, complex comorbidities, and improved survival of patients with challenging congenital or acquired airway anatomy all play important roles in assessing airway success.
In the 1980s and 1990s, the introduction to mass clinical practice of steadily improving flexible fiber-optic equipment resulted in significant advances in safety and likely decreased the need for surgical airway access. However, some limitations in the ability to intubate the trachea despite adequate visualization of the glottis were quickly described and conceptualized, with prescribed maneuvers to address the problem.1 Soon, combining supraglottic airway devices with flexible fiber-optic devices became a preferred method for difficult (asleep and awake) airway management techniques. The present variety of video-enhanced airway devices, such as video laryngoscopes and video stylets with fiber-optic and CCD (charge coupled device) and CMOS (complementary metal oxide semiconductor) image sensor technology, has brought further improvements in glottic visualization, but still cannot always guarantee successful passage of the endotracheal tube.2
Combining 2 of the newer technologically innovative devices such as a video laryngoscope and a flexible fiberscope can be complementary and prove critical in a situation where each might fail when deployed alone, even in the most skillful and experienced hands. Although reports of such complementary use are still relatively scarce and no specific recommendation is present in the main airway management algorithms,a it is very likely that a multitude of combinations has already been employed in clinical practice. In fact, such ideas and uses have certainly been around since the very first time curious colleagues found themselves in a crisis or in just another great teaching situation with 2 or more of these devices immediately at hand.
Multimodal Case Reports
The first such references reported difficult airway management in the ICU3 and video laryngoscopy (VL)–assisted fiber-optic intubation (FOI) for teaching purposes,4 respectively. The authors recognize that the video laryngoscope could be very useful to enhance the flexible FOI by lifting the tongue and jaw, and also when blood is found in the upper airway. In 2007, the first small clinical study of this complementary use described promising results using a similar method for “keeping the oropharynx open and reducing erratic lateral advancement,” while possibly reducing laryngoscopy force and allowing continuous visualization of the advancement of the endotracheal tube.5 The year before that, Xue et al reported, in a correspondence, their first experience with elective GlideScope-assisted awake FOI in 13 patients with predicted difficult airway.6 The authors suggested that VL could offer assistance in guiding the tip of the bronchoscope and identifying possible causes of resistance to endotracheal tube advancement. They also predicted that fiber-optic bronchoscopy could be performed more rapidly using a combined technique.
Subsequent case reports confirmed the utility and safety of such combined techniques in both awake and anesthetized patients in different difficult airway scenarios, such as morbid obesity,7 unexpected difficult intubation,8 post-radiation neck and airway changes,9 unstable C2 fracture,10 Cowden syndrome,11and occlusive airway mass,12 effectively preventing possible airway complications and use of surgical airway access.
The term multimodal airway approach as a reference to a combined intubation technique was first noted in a letter to the editor by Boet et al.13 Subsequent reports14-18 describe more cases of successful intubation with combined VL and flexible bronchoscopy, where bronchoscopy or VL alone have failed. The multiple suggestions and descriptions of the authors’ recommendations and practice, as well as teaching scenarios, reflect widening experience and acceptance of such combinations, as well as the increasing availability of advanced airway equipment. Weissbrod and Merati suggest the “smart stylet” concept, in which the entrance to the larynx is visualized by the video laryngoscope but the fiberscope is used only as a stylet with movable tip, not for visualization of the glottis.17 Van Zundert and Pieters report using a combination of video laryngoscope and video stylet.18
Five more publications of successful combined intubation complete the list of published reports to date (June 29, 2016), as indexed in PubMed.19-23 Four of these are case reports: a patient with a difficult airway and a failed intubation attempt with VL alone,19 a patient with a giant lymphocele,20 a patient with a laryngeal tumor,21 and a comatose patient post–cardiac arrest who was impossible to intubate using a conventional flexible scope and VL, in both the field and the emergency department.22 The authors of this last report suggested that the combination method is a viable alternative for a difficult airway and should be included in the emergency department’s difficult airway algorithm.22
Finally, another serious step toward “institutionalizing” the combined or multimodal airway approach was made by Lenhardt et al.23 The authors prospectively randomized 140 patients with anticipated difficult airways to tracheal intubation via VL with a preformed rigid stylet (control group) or via combined VL and flexible tracheoscopy (intervention group). While all patients were successfully intubated and the number of intubations requiring 2 or more attempts did not differ between the groups, 4 patients in the control group (all with cervical spine pathology) had to have their trachea intubated successfully with the combined method after 3 failed attempts using VL alone. The authors concluded that “flexible tracheoscope-assisted video laryngoscopic intubation is a feasible alternative to VL-only intubation in patients with predicted difficult airways,” and intubation success rate may be improved in selected patients, “particularly when in-line stabilization is required.”
We present here 2 additional cases of successful multimodal airway management, combining a video laryngoscope and a flexible fiberscope to achieve safe airway control in airway scenarios that proved otherwise impossible with conventional use of just 1 of these devices.
It is important to emphasize that the constantly and diligently updated difficult airway algorithms24,25 provide a valuable framework to address such potentially life-threatening situations in a controlled and safe manner. They also offer an expert way of thinking26 that often justifiably points toward conservative and/or well-established approaches when no clear outcome evidence exists in favor of the newer methods.
We submit that, when available and appropriately used, advanced airway management devices/techniques are complementary and their concomitant use may prove lifesaving in some patients and situations. As one expert puts it, “The practicing clinician may want to examine their existing difficult airway armamentarium and ask the question, ‘if one is good, maybe I can do better with two!’”27
This might provide grounds for consideration of such combinations to be included in difficult airway algorithms, as one more possible step before resorting to emergency surgical airway access. For example, and as a reflection of the described cases, a combination of VL and flexible fiberscope guidance could be included more specifically in the list of “alternative difficult airway approaches” in the 2013 ASA Difficult Airway Algorithm24 (Category B4-B evidence); we also suggest that this list of alternative approaches be a choice in the Awake Intubation limb of the algorithm.
- Katsnelson T, Frost EAM, Farcon E, et al. When the endotracheal tube will not pass over the flexible fiberoptic bronchoscope (letter). 1992;76:151-152.
- Kaplan MB, Berci G. Rigid videolaryngoscopy in the management of the difficult airway (letter).Can J Anesth. 2004;51:94.
- Hagberg CA, Westhofen P. A two-person technique for fiberscope-aided tracheal extubation/reintubation in intensive care unit (ICU) patients.J Clin Anesth. 2003;15:467-470.
- Doyle DJ. GlideScope-assisted fiberoptic intubation: a new airway teaching method (letter).2004;101:1252.
- Greib N, Stojeba N, Dow WA, et al. A combined rigid videolaryngoscopy-flexible fiberoscopy intubation technique under general anesthesia.Can J Anesth. 2007;54:492-493.
- Xue FS, Li CW, Zhang GH, et al. GlideScope-assisted awake fibreoptic intubation: initial experience in 13 patients. 2006;61:1014-1015.
- Moore MSR, Wong AB. GlideScope intubation assisted by fiber- optic scope.2007;106:885.
- Morillas Sendín P, del Olmo Rodríguez C, de Diego Isasa P, et al. [Combined use of the Glidescope and a fiberoptic bronchoscope in a case of unexpected difficult intubation].Rev Esp Anestesiol Reanim. 2008;55:454-455.
- Matioc AA. Use of the Airtraq with a fibreoptic bronchoscope in a difficult intubation outside the operating room.Can J Anaesth. 2008;55:561-562.
- Schoettker P, Bathory I, Broome M. Use of the nasotracheal Airtraq to assist difficult nasal fibreoptic intubation.Can J Anaesth. 2008;55:884.
- Sharma D, Kim LJ, Ghodke B. Successful airway management with combined use of Glidescope videolaryngoscope and fiberoptic bronchoscope in a patient with Cowden syndrome.2010;113:253-255.
- Choi GS, Park SI, Lee EH, et al. Awake Glidescope intubation in a patient with a huge and fixed supraglottic mass—a case report.Korean J Anesthesiol. 2010;59 Suppl:S26-S29.
- Boet S, Bould MD, Diemunsch PA. A combined rigid videolaryngoscopy-flexible bronchoscopy for intubation (letter).Korean J Anesthesiol. 2011;60:381-382.
- Gomez-Rios MA, Nieto Serradilla L. Combined use of an Airtraq optical laryngoscope, Airtraq video camera, Airtraq wireless monitor, and a fiberoptic bronchoscope after failed tracheal intubation.Can J Anaesth. 2011;58:411-412.
- Yuan YJ, Xue FS, Liao X, et al. Facilitating combined use of an Airtraq optical laryngoscope and a fiberoptic bronchoscope in patients with a difficult airway.Can J Anaesth. 2011;58:584-585.
- Wang Q, Xue FS, Liao X, et al. Tracheal intubations performed with a Macintosh laryngoscope and videolaryngoscopes on a mannequin simulating cardiac arrest.Can J Anaesth. 2011;58:967-968; author reply 968.
- Weissbrod PA, Merati AL. Reducing injury during video-assisted endotracheal intubation: the “smart stylet” concept. 2011;121:2391-2393.
- Van Zundert AA, Pieters BM. Combined technique using videolaryngoscopy and Bonfils for a difficult airway intubation.Br J Anaesth. 2012;108:327-328.
- Ara T, Mori G, Adachi E, et al. [Combined use of the GlideScope and fiberoptic bronchoscope for tracheal intubation in a patient with difficult airway].Masui. 2014;63:647-649.
- El-Tahan MR, Doyle DJ, Khidr AM, et al. Awake tracheal intubation with combined use of King Vision videolaryngoscope and a fiberoptic bronchoscope in a patient with giant lymphocele.Middle East J Anaesthesiol. 2014;22:609-612.
- Gaszynski T. A combination of KingVision video-laryngoscope and flexible fibroscope for awake intubation in patient with laryngeal tumor—case report and literature review.Anaesthesiol Intensive Ther. 2015;47:433-435.
- Sowers N, Kovacs G. Use of a flexible intubating scope in combination with a channeled video laryngoscope for managing a difficult airway in the emergency department.J Emerg Med. 2016;50:315-319.
- Lenhardt R, Burkhart MT, Brock GN, et al. Is video laryngoscope-assisted flexible tracheoscope intubation feasible for patients with predicted difficult airway? A prospective, randomized clinical trial.Anesth Analg. 2014;118:1259-1265. Erratum in:Anesth Analg. 2015;120:495.
- Apfelbaum JL, Hagberg CA, Caplan RA, et al. Practice guideline for management of the difficult airway: an updated report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway. 2013;118:251-270.
- Difficult Airway Society.das.uk.com/?home.
- Rosenblatt WH. The airway approach algorithm: a decision tree for organizing preoperative airway information.J Clin Anesth. 2004;16:312-316.
- Rosenblatt W. To pair is human.ambu.com/?Files/?%2FFiler%2FAEL.com%20Newsletters%2FSeptember Newsletter.html.