For these reasons, esophageal detector devices are not routinely recommended, particularly as a sole method for confirmation of endotracheal tube placement.

New techniques such as ultrasound imaging and transthoracic impedance methods offer potential in the detection and monitoring of the proper location of the tube.^17-21

Although these techniques currently may be helpful as adjuncts, they are relatively unproven and may not be widely available.

Ultimately, the evidence is currently insufficient to endorse widespread implementation of these technologies for this purpose.

Intubated patients often require procedures, repositioning, transport, and other movement while in the emergency department.

These events create a substantial potential for dislodgement of the endotracheal tube. Given the increased frequency of movements and transport in the emergency and acute care setting, assessment techniques for tube position should be used frequently.

Continuous endotracheal tube monitoring, such as with capnography, is recommended to assure prompt detection of endotracheal tube dislodgement from the trachea.

If the equipment for continuous monitoring of endotracheal tube position is not available, other methods should be used.

At a minimum, endotracheal tube placement should be recon-firmed promptly if the patient’s condition deteriorates but preferably before such a condition materializes.

Summary

At the time of initial intubation, proper endotracheal tube location should be verified for all patients. Failure to do so can lead to poor ventilation and oxygenation, and ultimately patient injury.

Several techniques exist to assure proper placement.

Chest and abdomen auscultation, pulse oximetry, chest radiography, and esophageal detector devices are helpful but have not been shown to be accurate in 100% of clinical encounters.

In the patient who has adequate tissue perfusion, these techniques are not comparable to end-tidal carbon dioxide assessment for the verification of endotracheal tube placement.

End-tidal carbon dioxide assessment is the preferred method for initial verification and continuous monitoring to assure proper location of the endotracheal tube.

The patient with poor perfusion offers unique challenges and additional techniques are typically necessary in these patients.

Other techniques for assessment of endotracheal tube location, such as ultrasound imaging and transthoracic impedance offer potential for the future. However, they are not currently endorsed for widespread implementation.

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