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Respiratory air Flow Transducer Based on air Turbulence

와류 현상을 이용하는 호흡기류센서

  • Kim, Kyung-Ah (Department of Biomedical Engineering, School of Medicine, Chungbuk National University) ;
  • Lee, In-Kwang (Department of Biomedical Engineering, School of Medicine, Chungbuk National University) ;
  • Park, Jun-Oh (Department of Biomedical Engineering, School of Medicine, Chungbuk National University) ;
  • Lee, Su-Ok (Department of Dental Hygiene, Daejeon Health Sciences College) ;
  • Shin, Eun-Young (Department of Biochemistry, School of Medicine, Chungbuk National University) ;
  • Kim, Yoon-Kee (School of Mechanical Engineering, Pusan National University) ;
  • Kim, Kyung-Chun (School of Mechanical Engineering, Pusan National University) ;
  • Cha, Eun-Jong (Department of Biomedical Engineering, School of Medicine, Chungbuk National University)
  • 김경아 (충북대학교 의과대학 의공학교실) ;
  • 이인광 (충북대학교 의과대학 의공학교실) ;
  • 박준오 (충북대학교 의과대학 의공학교실) ;
  • 이수옥 (대전보건대학 치위생과) ;
  • 신은영 (충북대학교 의과대학 생화학교실) ;
  • 김윤기 (부산대학교 공과대학 기계공학부) ;
  • 김경천 (부산대학교 공과대학 기계공학부) ;
  • 차은종 (충북대학교 의과대학 의공학교실)
  • Published : 2009.10.31

Abstract

The present study developed a new technique with no physical object on the flow stream but enabling the air flow measurement and easily incorporated with the devices for cardiopulmonary resuscitation(CPR) procedure. A turbulence chamber was formed in the middle of the respiratory tube by locally enlarging the cross-sectional area where the flow related turbulence was generated inducing energy loss which was in turn converted into pressure difference. The turbulence chamber was simply an empty enlarged air space, thus no physical object existed on the flow stream, but still the flow rate could be evaluated. Computer simulation demonstrated stable turbulence formation big enough to measure. Experiment was followed on the proto-type transducer, the results of which were within ${\pm}5%$ error compared to the simulation data. Both inspiratory and expiratory flows were obtained with symmetric measurement characteristics. Quadratic curve fitting provided excellent calibration formula with a correlation coefficient>0.999(P<0.0001) and the mean relative error<1%. The present results can be usefully applied to accurately monitor the air flow rate during CPR.

Keywords

References

  1. E.J. Cha, Measurements of the respiratory system, In: Medical instrumentation: Application and design, Seoul, Korea:Translated by the BME education consortium, Ryumoon-Kak, 1993, pp. 509-598
  2. C.H. Buess, and E.A. Koller, Pneumotachometers, In: Encyclopedia of medical devices and instrumentation, New York, U. S. A.: John Wiley & Sons, 1988, pp. 2319-2324
  3. Micro Medical Ltd., MicroLab Operating Manual, Kent, UK: Micro Medical Ltd., 1998, pp. 2-4
  4. K.A. Kim, H.S. Kim, T.S. Lee, and E.J. Cha, "Functional disposable use flow tube converting the respiratory air flow rate into averaged dynamic pressure", J. Sensors Soc., vol. 11, no. 3, pp. 125-131, 2002 https://doi.org/10.5369/JSST.2002.11.3.125
  5. A. Hald, and B. Stigsby, "Computerized hot-wire anemometry- Principles of calculation", Computer Programs in Biomedicine, vol. 11, no. 2, pp. 113-118, 1980 https://doi.org/10.1016/0010-468X(80)90119-1
  6. R.M. Olson, Flow measurements, In: Essentials of engineering fluid mechanics 4th ed., Athens, U. S. A.: Maple Press Company, Ohio University, 1980, pp. 452-482
  7. S.O. Hwang, and K.S. Lim, Cardiopulmonary resuscitation, In: Cardiopulmonary resuscitation and advanced cardiovascular life support, Seoul, Korea: Koonja, 2005, pp. 13-25
  8. S.O. Hwang, and K.S. Lim, Basic resuscitation, In: Cardiopulmonary resuscitation and advanced cardiovascular life support, Seoul, Korea: Koonja, 2005, pp. 27-62
  9. Korean Association of Cardiopulmonary Resuscitation, Guidelines of cardiopulmonary resuscitation, Seoul, Korea: Korean Association of Cardiopulmonary Resuscitation, 2007, pp. 1-18
  10. J.C. Shin, Flow in tube, In: Hydrodynamics, Seoul, Korea: Kuminsa, 2000, pp. 269-314
  11. A. Fleisch, "Der pneumotachography: ein Apparatzur Beischwindgkeitregstrierung der Atemluft", Arch. Ges. Physiol. vol.209, pp.713-722, 1925 https://doi.org/10.1007/BF01730956
  12. F. Rohrer, Physiologie der atembewegung, In: Handbuch der Normalen und Pathologischen Physiologie, Berlin, Germany:Springer-Verlag, 1925, pp.70-127
  13. American Thoracic Society, "Standardization of spirometry", Am. J. Respir. Crit. Care Med., vol. 152, pp. 1107-1136, 1995
  14. B.S. "Quality of cardiopulmonary resuscitation during out-of-hospital cardiac arrest", JAMA, vol. 293, no. 3, pp. 305-310, 2005 https://doi.org/10.1001/jama.293.3.305
  15. American Heart Association, "Guidelines for Cardiopulmonary Resuscitation Emergency Cardiovascular Care" Circulation, vol. 102, no. 1, pp. I1-I384, 2000
  16. K. Konno, and J. Mead, "Measurement of the separate volume changes of rib cage and abdomen during breathing", J. Appl. Physiol., vol. 22, no. 3, pp. 407-422, 1967
  17. K.A. Kim, S.S Kim, D.W. Cho, S.J. Lee, T.S. Lee, and E.J. Cha, "Characteristics of conductive rubber belt on the abdomen to monitor respiration", J. Sensors Soc., vol. 16, no. 1, pp. 24-32, 2007 https://doi.org/10.5369/JSST.2007.16.1.024
  18. I.K Lee, S.S Kim, J.C Jang, K.J. Kim, K.A. Kim, T.S. Lee, and E.J. Cha, "Wearable wireless respiratory monitoring system", J. Sensors Soc., vol. 17, no. 2, pp. 133-142, 2008 https://doi.org/10.5369/JSST.2008.17.2.133