An assessment of a tracheal tube introducer as an endotracheal tube placement confirmation device.

Introduction: Early detection of an inadvertent esophageal intubation can be particularly challenging in cases when the current standard of care, carbon dioxide detection, is unreliable. We sought to determine the sensitivity and specificity of an inexpensive and portable device, the gum elastic bougie (Eschmann Tracheal Tube Introducer, SIMS Portex, Inc, Keene, NH), as an endotracheal tube placement confirmation device.

Methods: We conducted a prospective blinded trial in 20 human cadavers. Each cadaver was randomized to a mixed series of 5 esophageal and 5 tracheal intubations. Each intubation was assessed with the bougie twice, once by a novice to the technique, and once by an assessor who was constant through the trial. Assessors used the bougie to "feel" for "clicks" of the tracheal rings and to appreciate "hang up" of the bougie as it was advanced into the smaller airways. Absence of these findings was presumed to indicate an esophageal intubation. Actual placement was confirmed by bronchoscopy. Each assessor made an independent determination of tube location. Descriptive statistics were used to summarize the data.

Results: Overall, 93% (95% confidence interval [CI], 86%-97%) of tracheal placements were correctly identified. The constant assessor was able to correctly identify 98% (95% CI, 90%-100%). Tracheal rings were detected in 92% of tracheal placements. Ring clicks were 95% specific for tracheal intubation. Hang up was reported in 100% of tracheal placements with a specificity of 84%. Overall, 95% (95% CI, 88%-98%) of esophageal intubations were detected. The constant assessor detected 100% of esophageal intubations.

Conclusion: In the cadaver model used in this study, the gum elastic bougie (Eschmann Tracheal Tube Introducer) shows promise as an endotracheal tube confirmation device.