Page 51 - JSOM Fall 2021

his or her needs. However, within the European Union cer- tubes of different lengths, might play a role in efficiency and
tification approval of medical devices, the NPA tube, when the time needed to provide an airway. The basics of train-
cut, loses its required European CE certification. This could ing must focus on the clinical outcome of the applied device,
become an important matter of discussion with manufacturers that is, establishing reliable airway management (solving the
of NPA tubes, allowing a certification with approval to cut A-problem according to the ATLS), stabilizing the patient, and
the NPA. Before deployment, soldiers could have their nose- observing clinically the patient’s respiration. In all training
tip-to-epiglottis distance measured (e.g., by MRI) and then programs, “gone wrong” examples must be taught, such as
be provided with the appropriate tube. (This would, how- adjusting the tube length until the defensive reflexes stop, us-
ever, apply only to soldiers and not the average emergency ing another tube length when one appears to be too short, or
patient.) This again makes it crucial to have a critical under- trying the other nostril if insertion did not work the first time.
standing of the intraoral distances, anatomy, and NPA devices A basic understanding of how to handle an airway problem
available. with the devices available is the overall goal.

Comparable studies regarding the optimal length of oropha- Acknowledgment
ryngeal airways have been published, for example, by Kim et Special thanks to Mrs Doris McGirt, RN, MSN, for her excep-
16
al. in 2016. They were able to determine the optimal length tional help on the subject.
for oropharyngeal airways (e.g., Guedel tubes), as indicated by
the distance of the maxillary incisors to the angle of the mandi- Author Contributions
ble. However, NPA study measurements remain heterogenous. AL formulated the initial question. Both authors structured
the research requirements. CSP conducted the research and
the evaluation. CSP and AL worked together to develop the
Conclusion
resulting implementations with regard to the requirements for
The NPA is a unique, simple piece of emergency equipment, an NPA and the corresponding training requirements. CSP
easy to use, inexpensive, and easily available in every trauma drafted the article with the assistance of AL. Both authors ap-
bag. It is very effective and shows advantages over oropha- proved the final manuscript.
2
ryngeal airways, yet it is still used less frequently. Perhaps the
guidelines need to be revised because, based on our reviewed Conflict of Interest Statement
studies, methods of sizing NPA tubes are perhaps inaccurate The authors declare no conflicts of interest.
and should no longer apply. There remains a lack of valuable
indicators to predict the optimal NPA tube length. The state- Financial Disclosure
ments in all of the above-mentioned studies were very heterog- The authors have indicated they have no financial relation-
enous; thus, our study questions could not be fully answered. ships relevant to this article to disclose.
There is some evidence that the correct length of NPA tubes
correlates with the patient’s height, independent of gender, and References
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