A Novel, Contactless, Portable “Spot-Check” Device Accurately Measures Respiratory Rate

Abstract

Respiratory rate (RR) is an important vital sign used in the initial and ongoing assessment of acutely ill patients. It is also used as a predictor of serious deterioration in a patient's clinical condition. Convenient electronic devices exist for measurement of pulse, blood pressure, oxygen saturation, and temperature. Although devices which measure RR exist, none has entered everyday clinical practice. We have developed a contactless portable respiratory rate monitor (CPRM) and evaluated the agreement in respiratory rate measurements between existing methods and our new device. The CPRM uses thermal anemometry to measure breath signals during inspiration and expiration. RR data were collected from 52 healthy adult volunteers using respiratory inductance plethysmography (RIP) bands (established contact method), visual counting of chest movements (established noncontact method), and the CPRM (new method), simultaneously. Two differently shaped funnel attachments to the CPRM were evaluated for each volunteer. Data showed a good agreement between measurements from the CPRM and the gold standard RIP, with intraclass correlation coefficient (ICC): 0.836, mean difference 0.46 and 95% limits of agreement of −5.90 to 6.83. When separate air inlet funnels of the CPRM were analyzed, stronger agreement was seen with an elliptical air inlet; ICC 0.908, mean difference 0.37 with 95% limits of agreement −4.35 to 5.08. A contactless device for accurately and quickly measuring respiratory rate will be an important triage tool in the clinical assessment of patients. More testing is needed to explore the reasons for outlying measurements and to evaluate in the clinical setting.

Algoritmically improved microwave radar monitors breathing more acurrate than sensorized belt

“…However, a plethora of breathing rate measurement methods, devices, and technologies exist 1 – 3 , 10 , 11 , most of which are contact-based. They include the following: infrared cameras and infrared thermography 12 – 15 ; video cameras, especially with motion magnification algorithms 16 – 18 ; fiber-optic s ensors 19 ; light intensity sensors 20 ; thermal imaging 21 ; thermistors 22 ; inductive sensors 23 ; impedance (transthoracic) sensors 24 ; ultrasonic transmitters and receivers 25 ; movement sensors (accelerometers, gyroscopes, magnetometer) 26 – 28 ; and microwave based on the Doppler effect (a comprehensive review is given in 29 ).…”