• The respiratory signal is separated and processed using acoustic signal processing that leverages Masimo Signal Extraction Technology (SET^®) to display continuous respiration rate (RRa) and an acoustic respiration waveform, a visualization of the vibrations caused by the patient’s airflow.
• Clinicians have the option to use the acoustic sensor to listen to the sound of a patient’s breathing remotely from a Masimo Patient SafetyNet™* view station.
• An adhesive Respiratory Acoustic Sensor (RAS) detects acoustic signals produced by the turbulent airflow in the upper airway that occurs during inhalation and exhalation, while signal processing algorithms convert the acoustic patterns into breath cycles to calculate respiration rate.
• Continuous monitoring of SpO₂ and RRa, as well as other physiologic parameters, on a single Masimo Pulse CO-Oximeter^® provides clinicians with more data to make informed care decisions and helps facilitate well rounded patient assessment.

In a study of 40 pediatric patients (12 months to 18 years of age) undergoing post-anesthesia care, in which researchers compared acoustic respiration rate monitoring using RRa to nasal capnography, impedance pneumography, and a reference method (counting breaths), researchers found that the difference in bias and precision between RRa and capnography was not significant, but that 97.5% of the patients (39) demonstrated good tolerance of the acoustic sensor, whereas 62.5% (25) demonstrated good tolerance of the nasal cannula. The researchers concluded, “Continuous respiration rate measurement from noninvasive, acoustic monitoring showed good agreement with nasal capnography, but was much better tolerated in post-surgical pediatric patients. Acoustic monitoring has the potential to increase the safety of pediatric patients by providing a reliable and accurate method for the continuous monitoring of respiration rate.”⁴