Acoustic Monitor Identifies Potential Airway Obstructions

A novel monitoring system continuously checks endotracheal tube (ETT) positioning during ventilation in neonates and infants.

The Medtronic (Dublin, Ireland) SonarMed airway monitoring system utilizes acoustic reflectometry technology to assist in verifying placement, movement, and obstruction of an ETT and its tip in neonates and infants provided with an ETT ranging 2.5-6.0 mm in diameter. Containing an embedded processor, a graphical display, a user input interface, and a serial communications interface, the system is attached noninvasively to the proximal end of the ETT by replacement of the standard 15-mm connector inside the ventilator circuit.


Acoustic reflectometry is measured using a single-patient EVA membrane sensor. The signals from the Sensor are displayed on the monitor, indicating to the clinician the baseline location of the ETT tip; an estimate of the passageway around the tip of the ETT, relative to ETT diameter; ETT movement relative to the baseline location; and ETT occlusion and obstruction data, including percent obstructed and location of the obstruction. The clinician can choose whether to view information in either a waveform or graphic on the Monitor’s LCD, and can also use the microphones to listen to breath sounds.

“Clinicians face unique challenges in the neonatal and pediatric ICU daily, ranging from managing oxygenation within extremely tight ranges, to keeping family members informed and comforted,” said Ariel MacTavish, president of the respiratory interventions business at Medtronic. “With our innovative technology, this fragile patient group is continuously monitored with a real-time and accurate device that may help improve a clinician's ability to manage the airway and enhance outcomes for our smallest, most vulnerable critical care patients.”

“SonarMed airway monitoring has revolutionized the way we care for our littlest patients. There is no other device in the world that can tell you where the endotracheal tube is located within the airway continuously in real-time, and whether the tube is obstructed or even partially occluded,” said neonatologist Jamie Powers, MD, MBA, of Huntington Hospital (Pasadena, CA, USA). “It also provides the care team and parents the added reassurance that the breathing tube is where it needs to be while repositioning the patient and during kangaroo care. In our institution it has become the new standard of care for all intubated infants.”

Annually, over 415,000 neonates and infants worldwide require invasive intubation and mechanical ventilation. But despite extensive reduction efforts, 75,000 (about one in five) will experience at least one unplanned extubation, which are a significant safety concern for neonates and newborns and are the most common adverse event during mechanical ventilation.