Sir,
Airway management in pediatric patients is considered to be more challenging than that in adults due to anatomical differences. Although successful laryngoscopy does not guarantee successful intubation, it is a pre-requisite for successful airway management. The larynx in infants is more cephalad and more anterior. The proximity of tongue to the larynx makes the visualization of laryngeal structures difficult, thus justifying the use of straight (Magill's) blade for laryngoscopy as it lifts the tongue more efficiently from the field of vision.[1,2] Moreover, the Magill's blade has minimal or no BLIND AREA. Blind area is the distance between the blade tip and the direct line of sight from eye to tongue inlet [Figure 1].[3] In the Magill's blade the reduced blind area is because of the flattened mid blade and thus it has reduced ‘crest of hill effect’ when compared with the Macintosh blade.[4] The clinical implication of blind area is that, on laryngoscopy, the area underneath is not visualized and this could lead to increased temptation to use levering and forceful action when used by inexperienced trainee. Considering this, straight blade should be the blade of choice as it has minimal blind area. The disadvantage of a straight blade is greater potential to damage the epiglottis due to its direct elevation than the curved blade, which lifts the epiglottis with the indirect approach.[4] There may be difficulty in inserting the endotracheal tube as it provides a narrow C-shaped channel to view the larynx.[4]
Figure 1.
Comparison of blind areas of Macintosh and magills laryngoscope blades
Cardiff pediatric laryngoscope is a modified pediatric laryngoscope, combining the features of both curved and straight blade that could be used in children of all ages [Figure 2]. The tip of the blade is slightly curved, but the proximal 6 cm of the Cardiff blade is straight with minimal blind area so that no part of the blade obscures the line of sight. The blade is Z-shaped in cross section and thus provides more room inside the mouth with less chances of obstructed view during tracheal intubation.[5–7] It also encourages the gentle indirect lift of the epiglottis and avoids unnecessary forceful action when compared to conventional straight and curved blades. Cardiff pediatric laryngoscope, with minimal blind area, appears to be superior to conventional straight and curved blades.
Figure 2.
Cardiff laryngoscope blade
References
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