We read with interest the approach to hyperangulated videolaryngoscopy recommended by Perry and Chrimes [1], which involves advancement of the stylet/tracheal tube alongside the blade, followed by timely stylet tilting to minimise posterior arytenoid impingement and anterior tracheal wall abutment. While the steps outlined closely match our own ‘in-plane’ technique, it is important to highlight that, if the posterior tilt is performed at the incorrect moment or excessively (in inexperienced hands), a loss of stylet angulation may occur (with malleable stylets) as the stylet can pivot against the tongue base, leading to subsequent posterior tube placement. Vigilance for potential right lateral maxillary incisor trauma during stylet tilting [2] must also be exercised.

Neither of these issues occur with our preferred ‘out-of-plane’ technique, where the stylet/tracheal tube are introduced at the angle of the mouth (at 90° to the midline/3 o'clock position [3]; Fig. 1), advanced until the tracheal tube tip appears on screen, then rotated anti-clockwise towards the midline (blind rotation should ideally be avoided). This approach is particularly useful when the mouth opening of the patient is restricted, requires no additional time to perform, almost always delivers the tracheal tube tip at the level of the glottis (rather than below it) and often follows a more favourable trajectory for tracheal tube passage through the glottis. We recommend holding the stylet/tracheal tube as proximally as possible as this confers the greatest tracheal tube tip manoeuvrability; and the stylet size must match the selected tracheal tube diameter (an overly slim stylet can lead to unwanted rotation within the tube lumen and loss of directional control). Stylet manipulation, like many aspects of hyperangulated videolaryngoscopy, requires finesse not force.

In keeping with this mantra, we also advocate holding the videolaryngoscope handle between thumb, index and middle finger (rather than the traditional full-palm grip) as this clearly differentiates hyperangulated videolaryngoscopy from Macintosh-style videolaryngoscopy for learners, improves manoeuvrability, deters excessive blade advancement and/or lifting force and allows simultaneous fine adjustments of blade tip and stylet to seamlessly align glottic orientation with tracheal tube trajectory – maximising first pass tracheal intubation success without incurring trauma.

Much like in- and out-of-plane ultrasound techniques, we advocate learning and practising both hyperangulated videolaryngoscopy approaches, as this promotes flexibility in the face of variable anatomical/pathological airway management challenges.

我们饶有兴趣地阅读了 Perry 和 Chrimes 推荐的超成角视频喉镜手术 [1]，该方法包括将管心针/气管管管沿刀片推进，然后及时倾斜管心针，以尽量减少后杓状软骨撞击和气管前壁基台。虽然概述的步骤与我们自己的“平面内”技术非常匹配，但重要的是要强调，如果在不正确的时刻或过度（在没有经验的手中）进行后倾斜，则可能会出现管心针角度的损失（使用可塑性管心针），因为管心针可以顶住舌根，导致随后的后管放置。还必须警惕管心针倾斜过程中潜在的右上颌切牙创伤 [2]。

我们首选的“平面外”技术不会出现这些问题，其中管心针/气管管导管以口腔的角度引入（与中线/3 点钟位置成 90° [3];图 1），前进直到气管插管尖端出现在屏幕上，然后逆时针向中线旋转（理想情况下应避免盲目旋转）。当患者的张口度受到限制时，这种方法特别有用，不需要额外的时间来执行，几乎总是在声门水平（而不是低于声门）输送气管插管尖端，并且通常遵循更有利的轨迹通过声门。我们建议将管心针/气管管导管尽可能靠近近端，因为这赋予了最大的气管插管尖端可操作性;并且管心针尺寸必须与所选的气管直径相匹配（过于细的管心针会导致管腔内不必要的旋转并失去方向控制）。与超成角视频喉镜检查的许多方面一样，管心针操作需要技巧而不是力量。

为了与这一口号保持一致，我们还提倡用拇指、食指和中指握住视频喉镜手柄（而不是传统的全掌握法），因为这可以明显区分超成角视频喉镜检查与学习者的 Macintosh 式视频喉镜检查，提高可操作性，阻止刀片过度推进和/或提升力，并允许同时微调刀片尖端和管心针，以无缝对齐声门方向与气管插管轨迹– 在不造成创伤的情况下最大限度地提高首次气管插管的成功率。

与平面内和平面外超声技术非常相似，我们提倡学习和实践两种超成角视频喉镜方法，因为这可以提高面对可变解剖/病理气道管理挑战的灵活性。