Abstract

Conventional direct laryngoscopy (DL) has been invented and clinically applied for almost two centuries.¹ Later, the new design of laryngoscopes and blades (e.g., Macintosh style) improved and broadened its clinical use.^2,3 Several external laryngeal maneuvers, together with sniffing positioning, have been shown to better align with three axes during tracheal intubation using laryngoscopy.⁴ However, even though various airway prediction methods have been proposed, difficult airway events using laryngoscopy for tracheal intubation occur on daily basis. Several issues have been occasionally encountered when anesthesiologists use laryngoscopy for tracheal intubation, including difficult laryngoscopic blading, difficult full-glottic visualization, and difficult insertion of an endotracheal tube into the trachea.^5-7

To solve the issues of difficult tracheal intubation and inadequate glottis visualization (e.g., due to limited cervical spine mobility, morbid obesity, oropharyngeal tumor, etc.), videolaryngoscopy (VL) with video-enhanced visualization of the larynx has been invented two decades ago.⁸ Since then, the newly emerging role of VL for difficult intubation (perhaps also for routine intubation) has been extensively studied. Meanwhile, in contrast to DL and VL, several rigid intubating laryngoscopes (Bullard, Wu, Upsher, etc.) and semi-rigid intubating stylet (Bonfils) appeared and proposed to apply for difficult intubation. Since a new seeing stylet-scope was invented and modified,⁹ a small group of airway operators has applied the video-assisted intubating stylet (VS) for daily routine and emergency tracheal intubation during the last decade.¹⁰ Such application of VS has been widely demonstrated in certain predicted difficult airway scenarios.^11-19 Therefore, we coined the term “styletubation” for tracheal intubation using such VS technique for airway management. It is a style of tracheal intubation when the airway operator applied VS technique (also named as Shikani technique) for both routine and emergency tracheal intubation. The styletubation can be performed by a single airway operator or together with an airway assistant. The technique can be conducted either with the aid of the operator’s non-dominant hand, DL, VL, or a tongue blade (Figure 1). The degree of difficult styletubation can be categorized into three levels (LQS grading system). Grade 1 is defined as any part of glottis which can be seen in front of the epiglottis with the help of a jaw thrust maneuver. Grade 2 is then defined as no part of glottis which can be observed but still enough space beneath the epiglottis allows the stylet-endotracheal tube set to pass through. Grade 3, the trickiest one, is defined as the epiglottis dropped and lying down against the posterior pharyngeal wall (Figure 2, the first column).

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Fig. 1. The Styletubation in a Mannequin Model

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Fig. 2. The Clinical Application of the Styletubation for Routine Tracheal Intubation in Three Patients

With the styletubation for tracheal intubation for regular surgeries, it is reasonable to compare its effectiveness and safety performance outcomes with other airway modalities (Table 1). With our vast use experiences of the styletubation (in more than 7,000 patients/year in a tertiary medical center), we found that this technique is swift (the time to intubate: from 3 seconds to 10 seconds), smooth (first-attempt success rate: 100%), safe (no airway complications), and easy (high subjective satisfaction and fast learning curve). To see is to believe, we encourage the readers to look into the videotape recordings we provided (the supplementary materials: Supplement Videos 1–3) and challenge the paradigmatic role of the styletubation.

Table 1. Comparison of DL, VL, FOB, and VS (Styletubation) for Tracheal Intubation: Generalized Advantages and Disadvantages

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Ethical Approval of Studies

The study was conducted according to the guidelines of the Declaration of Helsinki, and approved by REC, Hualien Tzuchi Hospital (Approved letter number: CR112-04).

Informed Consent

Written informed consent documents were obtained from the patients.

References