**6. Future perspectives**

VL for tracheal intubation has been the norm for tracheal intubation for several decades [50, 239]. Since the introduction of the Shikani video-associated stylet technique for intubation in 1999 [6], numerous commercially available video-assisted

#### **Figure 41.**

*Video-video paired technique for tracheal intubation. This is a 68-year-old man with BMI 25.9 kg/m<sup>2</sup> . Vitrectomy was scheduled for recurrent total retinal detachment. VL was used as an adjunct to VS. (A) A flat epiglottis. (B) Cormack-Lehane grade IIa. (C) Passage of the VS stylet-ET tube into vocal cords. (D) Entry of the ET tube into trachea. The same patient as in Figure 42. (Also see the Supplementary Materials Video S32).*

#### **Figure 42.**

*Views from VS camera. The same patient as in Figure 41. After glottis views were obtained by VL, the VS was inserted and advanced. (A) Oropharynx. (B) Larynx. LQS score grade 1. (C) Full glottis view. (D) Entry into trachea. It is noted that, with the help of VL, the airway is wide open and a perfect glottis view is easy to obtain. The intubation time is 14 s. (Also see the Supplementary Materials Video S33).*

#### **Figure 43.**

*Video-video paired technique for tracheal intubation. This 68-year-old man (BMI 26.8 kg/m2 ) underwent a bipolar hemiarthroplasty due to femoral neck fracture. Past history includes lung adenocarcinoma and cervical spine stenosis (C3-6). VL was used as an adjunct to VS. (A) Uvula. (B–E) An omega-shaped epiglottis. (C) Cormack-Lehane grade I. (D, E) Passage of the VS stylet-ET tube into vocal cords. (F) Entry of the ET tube into trachea. The same patient as in Figure 44. (Also see the Supplementary Materials Video S34).*

#### **Figure 44.**

*Views from VS camera. The same patient as in Figure 43. After glottis views were obtained by VL, the VS was inserted and advanced. (A) Oropharynx. (B, C) Larynx. LQS score grade 1. (D, E) Full glottis view. (F) Entry into trachea. The intubation time is 15 s. (Also see the Supplementary Materials Video S35).*

intubating stylet products have been brought to market. Some of the advantages of the VS technique include maneuverability, better visualization, the ability to negotiate a confined oropharyngeal space, the ability to avoid any trauma to the airway or the teeth, ease of use, and affordability. A high first-attempt success rate, shorter intubation time, and less trauma are additional advantages which lead to less autonomic stimulation. These advantages are why VS has been overwhelmingly accepted and the most prevalent intubating tool in Taiwan since 2016. We hope that this review article will educate intubation providers from various regions of the world and make VS accepted universally. It is still to be determined whether VS will become a first-line technique in the airway guidelines for routine intubations, or whether it will be restricted to more challenging airways situations.
