Real-Time Optical Monitoring of Endotracheal Tube Displacement

Abstract

Proper ventilation of a patient with an endotracheal tube (ETT) requires proper placement of the ETT. We present a sensitive, noninvasive, operator-free, and cost-effective optical sensor, called Opt-ETT, for the real-time assessment of ETT placement and alerting of the clinical care team should the ETT become displaced. The Opt-ETT uses a side-firing optical fiber, a near-infrared light-emitting diode, two photodetectors with an integrated amplifier, an Arduino board, and a computer loaded with a custom LabVIEW program to monitor the position of the endotracheal tube inside the windpipe. The Opt-ETT generates a visual and audible warning if the tube moves over a distance set by the operator. Displacement prediction is made using a second-order polynomial fit to the voltages measured from each detector. The system is tested on ex vivo porcine tissues, and the accuracy is determined to be better than 1.0 mm. In vivo experiments with a pig are conducted to test the performance and usability of the system.

Antimicrobial Solutions for Endotracheal Tubes in Prevention of Ventilator-Associated Pneumonia

“…appropriate depth of the medical device [42][43][44]. Usually, the ETT is introduced on the right side of the laryngoscope.…”

“…It contains a marking of length expressed in centimeters that helps the clinicians to introduce the tube inside the human body and carefully control its movements. Also, a continuous radiopaque marking is embedded along the tube length to permit X-ray identification in the chest area and to estimate the appropriate depth of the medical device [ 42 , 43 , 44 ]. Usually, the ETT is introduced on the right side of the laryngoscope.…”

Continuous monitoring of endotracheal tube position with near infrared light

“…We recently reported the proof of concept of a novel device based on near-infrared (NIR) light propagation in trachea tissue, named Opt-ETT for continuous monitoring of ETT position 28 . Opt-ETT consists of a side-firing optical fiber attached to the ETT for trachea illumination and a detector board with two phototransistors for light detection.…”

“…We recently reported the proof of concept of a novel device based on near-infrared (NIR) light propagation in trachea tissue, named Opt-ETT for continuous monitoring of ETT position. 28 Opt-ETT consists of a side-firing optical fiber attached to the ETT for trachea illumination and a detector board with two phototransistors for light detection. The NIR wavelength of 810 nm is selected for its low tissue absorption and scattering, which allows a deep penetration depth, relatively low NIR background in most operating rooms and ICUs and its compatibility with low-cost silicon-based detectors.…”