Measurement of respiratory rate with high-resolution accelerometer and emfit pressure sensor

Respiratory rate is an essential parameter in the clinical monitoring of hospital patients. It can be measured in various ways, such as by recording chest movements, breathing flow or heart rate variations. Current sensor technology allows the development of new kinds of convenient and portable respiratory rate recorders, including smart shirts, which enable more efficient healthcare processes in hospitals. This study carried out respiratory rate measurements using a sensor belt with a high-resolution accelerometer (capacitive MEMS) and an EMFit (electret film) pressure sensor. Results obtained from tests on 10 subjects showed that both sensors are feasible for respiratory rate measurement; the reliability of the MEMS was 90%, while that of the EMFit was 90- 100%. In addition, the results showed that the location of the sensor module on the chest is important.

[1]  J. Siivola,et al.  ETMF-polymer transducer as a detector of respiration in humans , 1993, Medical and Biological Engineering and Computing.

[2]  R. Morgan,et al.  An early warning scoring system for detecting developing critical illness , 1997 .

[3]  Y. Yonezawa,et al.  An ECG electrode-mounted heart rate, respiratory rhythm, posture and behavior recording system , 2004, The 26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[4]  Jukka Lekkala,et al.  ElectroMechanical Film (EMFi) — a new multipurpose electret material , 2000 .

[5]  A. Varri,et al.  A new method for measuring the ballistocardiogram using EMFi sensors in a normal chair , 2004, The 26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[6]  A. Tura,et al.  A Medical Wearable Device with Wireless Bluetooth-based Data Transmission , 2003 .

[7]  Hannu Sorvoja,et al.  Use of EMFi as a blood pressure pulse transducer , 2005, IEEE Transactions on Instrumentation and Measurement.

[8]  Donald M Yealy,et al.  Prospective comparison of three validated prediction rules for prognosis in community-acquired pneumonia. , 2005, The American journal of medicine.

[9]  Alex Pentland,et al.  Wearable feedback systems for rehabilitation , 2005, Journal of NeuroEngineering and Rehabilitation.

[10]  B. Carlson,et al.  Evaluation of a non-invasive respiratory monitoring system for sleeping subjects , 1999, Physiological measurement.

[11]  J.A. Fiz,et al.  Assessment of respiratory muscle effort studying diaphragm movement registered with surface sensors. Animal model (dogs) , 2004, The 26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[12]  F McArthur-Rouse,et al.  Critical care outreach services and early warning scoring systems: a review of the literature. , 2001, Journal of advanced nursing.