A Portable Auto-Detective Instrument for Endotracheal Intubation

Endotracheal intubation is the most important method of setting up a definite airway. Timely assessment of proper endotracheal tube (ET) placement is necessary to avoid serious morbidity and mortality. Many methods of confirmation endotracheal tube are suggested by ACLS (advanced cardiac life support) guideline 2005, such as capnometry (end-tidal CO₂ monitoring) and esophageal detector devices (EDDs). Unfortunately there are inherent limitations to the common methods used to verify tube placement. Procedures to evaluate tube position must be simple, reliable, inexpensive and rapidly applicable in order to achieve widespread acceptance. We developed an auto-detective instrument and conducted an animal study to create a new method identifying the esophageal intubation by different cuff pressure of endotracheal tube in esophagus which is anatomically and physiologically smaller, less rigid and much elastic than tracheal. Different cuff volume results in different cuff pressure in these two anatomic structures. The portable auto-detective instrument with an automatic cuff inflating mechanism and a cuff pressure-volume sensor chip can record the pressure-volume differences and show dynamic curves in tracheal and esophagus. The differences of pressure-volume of in esophagus and tracheal will be collected and analyzed in order to distinguish esophageal intubation and tracheal intubation.