Abstract

---

Background:Glidescope guided double lumen endobronchial tube (DLT) placement in the difficult airway warranted the need for dedicated rigid stylet development.
Methods:Verathon Inc. Bothell WA recently introduced the GlideRite® DLT Stylet for DLT placement in difficult airway. We used it in a patient with difficult airway scheduled for thoracotomy.
Results:We observed in-vivo and re-tested in-vitro that the GlideRite® DLT Stylet use may distort the distal end of DLT’s bronchial lumen that may increase the peak airway pressures with the possibility of pressure injury to the bronchial wall and may not allow adequate lobar ventilation through the bronchial lumen.
Conclusion:Our team’s limited experience with the GlideRite® DLT Stylet suggests that: (a) it will not be advisable to use the GlideRite® DLT Stylet without the tracheal lumen positioning pin, (b) if possible, the distal end of the GlideRite® DLT Stylet should not be far advanced into the distal end of the bronchial lumen to minimize the alteration of the distal end of the bronchial lumen, (c) if high peak airway pressures persists, the DLT should be exchanged with a new DLT, and (d) it remains to be seen how this minimal alteration of the distal bronchial lumen interferes with much more challenging correct placement of the right sided DLT.

Introduction

---

Glidescope® guided double lumen endobronchial tube (DLT) placement warranted the need for dedicated rigid stylet development. Verathon Inc. Bothell WA recently introduced the GlideRite® DLT Stylet with this goal. We hereby report our observation that its use may distort the distal end of DLT’s bronchial lumen that may increase the peak airway pressures with the possibility of pressure injury to the bronchial wall and may not allow adequate lobar ventilation through the bronchial lumen.

Case Report(s)

---

In a patient undergoing right thoracotomy for the right upper lobe resection secondary to the right upper lobe lung cancer, the GlideRite® DLT Stylet for aiding DLT placement in the anticipated difficult airway was used per the manufacturer’s instructional bronchure [1]. When fiberoptic bronchoscopy was performed through the bronchial lumen, the bronchial tip was partially opposing the medial side wall of the left main bronchus with only a small opening into the left main bronchus to negotiate the bronchoscope. As the case progressed and left-sided one lung ventilation was initiated, the peak airway pressures rose to 40 mmHg with plateau pressures of 26 mmHg. This was thought to be due to the partial apposition of the left main bronchus to the distal end of bronchial lumen of DLT. It was decided to not exchange the DLT with a new one as pressure control ventilation kept the peak airway pressures under 32 mmHg with no change in plateau pressure. The rest of the perioperative period was uneventful.

Discussion

---

To understand the ventilation issues encountered by our team with the use of the GlideRite® DLT Stylet, we decided to test this stylet in a larynx, airway and carina manikin.  The following conclusions were made: compared to the malleable stylet provided with the DLT, the GlideRite® DLT Stylet advances further in the distal bronchial lumen of the DLT (Figure 1) that increase the curvature of distal bronchial lumen of DLT by six degrees medially (23 degrees angle to tracheal axis) compared to the DLT pre-formed on the malleable stylet (29 degrees angle to tracheal axis) (Figure 2). When the tracheal lumen positioning pin of GlideRite® DLT Stylet is not accommodated at all, the curvature of distal bronchial lumen of DLT increases by 10 degrees laterally (39 degrees angle to tracheal axis). This mild but clinically appreciable alteration of the distal bronchial lumen by the GlideRite® DLT Stylet can be avoided with fiberoptic bronchoscope assisted DLT placement across the vocal cords under the direct vision of the Glidescope®. However, the short length (60 cm) of the fiberscope interferes with fiberoptic bronchoscope assisted DLT placement because the length of the DLT is 41 cm and front teeth to carina distance is usually at least 20 cm [2]; and these distances do not allow direct placement of the fiberoptic bronchoscope in the main bronchus before initiation of the threading of the DLT on the bronchoscope. Direct placement of the fiberoptic bronchoscope in the main bronchus is essential to avoid the intra-tracheal bronchoscope getting entangled between the advancing DLT’s bronchial lumen and the tracheal wall. This entanglement increases the strain on the bronchoscope and may damage the fiberscope. The solution may be a longer bronchoscope (at least 70 cm in length) that can overcome its limitation for DLT placement.

Conclusion

---

In summary, our team’s limited experience with the GlideRite® DLT Stylet suggests that: (a) it will not be advisable to use the GlideRite® DLT Stylet without the tracheal lumen positioning pin, (b) if possible, the distal end of the GlideRite® DLT Stylet should not be far advanced into the distal end of the bronchial lumen to minimize the alteration of the distal end of the bronchial lumen , (c) if high peak airway pressures persists, the DLT should be exchanged to avoid high pressure exposure to the bronchial wall, and (d) it remains to be seen how this minimal alteration of the distal bronchial lumen interferes with much more challenging correct placement of the right sided DLT.

Acknowledgement(s)

---

The authors are sincerely thankful to Fred Schneider, CRNA, and Chica Kuzumi MD, Department of Anesthesiology, Veterans’ Medical Center, Detroit for their scientific insights, suggestions and discussions regarding the fiberoptic bronchoscope assisted DLT placement in difficult airway.

References

---

1.http://www.verathon.com/PDFs/0900-2834-00-60.pdf Last accessed on November 27, 2010.
2.Hunyady AI, Pieters B, Johnston TA, Jonmarker C. Front teeth-to-carina distance in children undergoing cardiac catheterization. Anesthesiology 2008; 108: 1004-8.

Source(s) of Funding

---

None

Competing Interests

---

None

Disclaimer

---

This article has been downloaded from WebmedCentral. With our unique author driven post publication peer review, contents posted on this web portal do not undergo any prepublication peer or editorial review. It is completely the responsibility of the authors to ensure not only scientific and ethical standards of the manuscript but also its grammatical accuracy. Authors must ensure that they obtain all the necessary permissions before submitting any information that requires obtaining a consent or approval from a third party. Authors should also ensure not to submit any information which they do not have the copyright of or of which they have transferred the copyrights to a third party.
Contents on WebmedCentral are purely for biomedical researchers and scientists. They are not meant to cater to the needs of an individual patient. The web portal or any content(s) therein is neither designed to support, nor replace, the relationship that exists between a patient/site visitor and his/her physician. Your use of the WebmedCentral site and its contents is entirely at your own risk. We do not take any responsibility for any harm that you may suffer or inflict on a third person by following the contents of this website.