|LETTER TO EDITOR
|Year : 2020 | Volume
| Issue : 3 | Page : 159-160
A variation in the Macintosh laryngoscope design: Is it really helpful?
Priya Rudingwa, Meenupriya Arasu, Balaji Kannamani, Sakthirajan Panneerselvam
Department of Anaesthesia and Critical Care, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
|Date of Submission||19-Sep-2020|
|Date of Acceptance||08-Oct-2020|
|Date of Web Publication||25-Dec-2020|
Dr. Meenupriya Arasu
Department of Anaesthesia and Critical Care, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry - 605 006
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Rudingwa P, Arasu M, Kannamani B, Panneerselvam S. A variation in the Macintosh laryngoscope design: Is it really helpful?. Airway 2020;3:159-60
|How to cite this URL:|
Rudingwa P, Arasu M, Kannamani B, Panneerselvam S. A variation in the Macintosh laryngoscope design: Is it really helpful?. Airway [serial online] 2020 [cited 2021 Jan 27];3:159-60. Available from: https://www.arwy.org/text.asp?2020/3/3/159/304849
Airway management in infants is challenging and unique taking into consideration the anatomical and physiological differences from that of adults. The high oxygen requirement and the unfavourable ratio of alveolar ventilation to functional residual capacity provide limited safe apnoea time during laryngoscopy. The choice of laryngoscope blade depends on the preference and experience of the anaesthesiologist. Although the Miller blade is recommended for children below 2 years, it has not been found to provide better intubating conditions as compared to that of the Macintosh blade. The availability of a zero size and the acquaintance with Macintosh blade could be a reason for its preference in infants.
We would like to share our experience while using a modified Macintosh blade (size 0) with an altered design which led to an unfavourable view during laryngoscopy. The original Macintosh laryngoscope (available as the English profile) [Figure 1] has a smooth, gentle curve and a flange that starts at the base and continues to the tip in a gradually narrowing manner. The modified Macintosh blade (available as the American profile) has an abrupt curvature, the flange and the web end midway proximal to the tip [Figure 1]. The absence of the web in the distal part of the modified Macintosh blade (American profile) causes the relatively large tongue in infants to hang over the blade and bulb, obscuring the view of the glottis and leading to suboptimal lighting. This further results in a reduction of the space available for the advancement of the endotracheal tube.
|Figure 1: (a and b) Side and front views of the modified size 0 Macintosh blade (American profile) (marked with an arrow) and the standard size 0 Macintosh blade (English profile)|
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This alteration in design has probably been made with an intention to make the blade less bulky and the tip smaller, which would allow more space for negotiation of the endotracheal tube. On the contrary, we found that by compromising the view and illumination, this modification makes laryngoscopy difficult even for experienced anaesthesiologists while intubating eight infants with normal airways. However, under the same intubating conditions, transition to the Macintosh blade (English profile) obviated the difficulty, resulting in successful intubation. Considering these issues, we would like to suggest that caution has to be exercised while using the Macintosh blade (American profile) in infants. Although with experience one may gain expertise in its use, novices may encounter this difficulty which could potentially increase the number of laryngoscopy attempts and lead to airway injury in infants. Hence, it would be pragmatic to keep a standard Macintosh blade or Miller blade as a standby should this problem be encountered.
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Conflicts of interest
There are no conflicts of interest.
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