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Development of an Automatic Blood Pressure Device based on Korotkoff Sounds

  • Li, Xiong (Dept of Electronic Engineering, Chonbuk National University) ;
  • Im, Jae Joong (Dept of Electronic Engineering, Chonbuk National University)
  • Received : 2019.06.08
  • Accepted : 2019.06.16
  • Published : 2019.06.30

Abstract

In this study, we develop a Korotkoff sound based automatic blood pressure measurement device including sensor, hardware, and analysis algorithm. PVDF-based sensor pattern was developed to function as a vibration sensor to detect of Korotkoff sounds, and the film's output was connected to an impedance-matching circuit. An algorithm for determining starting and ending points of the Korotkoff sounds was established, and clinical data from subjects were acquired and analyzed to find the relationship between the values obtained by the auscultatory method and from the developed device. The results from 86 out of 90 systolic measurements and 84 out of 90 diastolic measurements indicate that the developed device pass the validation criteria of the international protocol. Correlation coefficients for the values obtained by the auscultatory method and from the developed device were 0.982 and 0.980 for systolic and diastolic blood pressure, respectively. Blood pressure measurements based on Korotkoff sound signals obtained by using the developed PVDF film-based sensor module are accurate and highly correlated with measurements obtained by the traditional auscultatory method.

Keywords

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Figure 1. Sensing module (left) and schematic diagram of sensing module (right)

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Figure 2. Pulse waves before cuff inflation and without a signal filter

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Figure 4. Developed device including sensor implemented inside the cuff

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Figure 5. Korotkoff sounds (top) and the corresponding cuff pressure (bottom)

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Figure 6. Determination of systolic and diastolic pressure based on Korotkoff sounds and cuff pressure. (a) raw Korotkoff sounds, (b) square wave indicates detection of Korotkoff sound after rectification, and (c) determination of Korotkoff sounds above the preset threshold

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Figure 7. Top, Korotkoff sounds; middle, cuff pressure; bottom, pulse waves

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Figure 8. Correlation between auscultatory method and PVDF device measurements of systolic (left) and diastolic (right) blood pressures

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Figure 9. Difference values between auscultatory method and developed device for systolic (left) and diastolic (right) pressures

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Figure 10. Bland-Altman plots device for systolic (left) and diastolic (right) pressures obtained by the auscultatory method and the developed device.

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Figure 3(a). Output of sensing module with a 4th order 15Hz high-pass filter before cuff inflation

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Figure 3(b). Output of sensing module with a 4th order 25Hz high-pass filter during cuff deflation

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Figure 3(c). Output of sensing module after applying a 4th order 35Hz high-pass filter showing Korotkoff sounds

Table 1. Mean and standard deviations of blood pressures obtained by the auscultatory method and from the developed device for 10 subjects

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References

  1. Stamier J., Neaton J. D., Wentworth, D. N. "Blood pressure (systolic and diastolic) and risk fatal coronary heart disease," Hypertension, 3(5 Suppl):I2-12, 1989.
  2. Williams J.S., Brown S.M., Conlin P.R. "Blood-pressure measurement," N Engl J Med 2009; 360:e6. DOI: 10.12691/ajhr-1-1-6.
  3. Guyenet P. G. "The sympathetic control of blood pressure," Nature review neuroscience 7(5): 335-346, 2006. DOI: 10.1038/nrn1902
  4. Poulter N. R., Prabhakaran D., Caulfield M. "Hypertension," Lancet. 386(9995):801-12, 2015. DOI: 10.1016/S0140-6736(14)61468-9
  5. Lackland D. T., Weber M. A. "Global burden of cardiovascular disase and stroke: hypertension at the core," The Canadian journal of cardiology. 31(5): 569-71. DOI: 10.1016/j.cjca.2015.01.009
  6. O'Brien E, Parati G, Stergiou G et al. "European Society of Hypertension position paper on ambulatory blood pressure monitoring," J Hypertens, 31: 1731-1768, 2013. DOI: 10.1097/HJH.0b013e328363e964.
  7. Mancia G, Fagard R, Narkiewicz K et al. "2013 ESH/ESC guidelines for the management of arterial hypertension," Eur Heart J, 34: 2159-2219, 2013. DOI: 10.1097/01.hjh.0000431740.32696.cc.
  8. Pickering T. G., Hall H. E., Appel L. J., et al. "Recommendation for blood pressure measurement in humans and experimental animals part 1: blood pressure measurement in humans: a statement of professionals from the subcommittee of professional and public education of the American heart association council on high blood pressure research," Hypertension. 45(1):142-161, 2005. DOI: 10.1161/01.CIR.0000154900.76284.F6
  9. O'Brien E, Fitzgerald D. "The history of blood pressure measurement," J Hum Hypertens 8(2):73-84, 1994.
  10. Bevan A.T., Honour A.J., Stott F.H., "Direct arterial pressure recording in unrestricted man," Br Heart J 31(3):387-388, 1969.
  11. Myers M.G, Godwin M, Dawes M, Kiss A, Tobe S.W., Kaczorowski J. "The conventional versus automated measurement of blood pressure in the office (CAMBO) trial: masked hypertension sub-study," J Hypertens. 30:1937-1941, 2012. DOI: 10.1097/HJH.0b013e328356abd3
  12. Armstrong R. S. "Nurses' knowledge of error in blood pressure measurement technique," International journal of nursing practice. 8(3):118-126, 2002. DOI: 10.1046/j.1440-172X.2002.00348.x
  13. Drzewiecki G. M., Melbin J., Noordergraaf A. "The korotkoff sound," Ann Biome Eng. 17: 325-359, 1989. DOI: 10.1007/BF02368055
  14. Geddes L. A., Voelz M., Combs C., Reiner D., Babbs C. F. "Charactrerization of the oscillometric method for measuring indirect blood pressure" Annals of biomedical engineering, 10(6):271-280, 1982. https://doi.org/10.1007/BF02367308
  15. Zheng D, Amoore JN, Mieke S, Smith FE, King ST, Murray A. "Automated Blood Pressure Measurement: Reasons for Measurement Variability Uncovered," Computers in Cardiology, 36:21-24, 2009.
  16. Van Montfrans G. A. "Oscillometric blood pressure measurement: progress and problems," Blood press monit. 6(6):287-90, 2001. https://doi.org/10.1097/00126097-200112000-00004
  17. Raamat R., Talts J., Jagomagi K., Kivastik J. "Errors of oscillometric blood pressure measurement as predicted by simulation," Blood press monit, 16(5): 238-245, 2011. DOI:10.1097/MBP.0b013e32834af752
  18. Li X., Gayathri P., Im J. J. "A study for the development of K-sound based automatic blood pressure device using PVDF film," 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2016. DOI: 10.1109/EMBC.2016.7590688
  19. John A, Tobias G, al, "Characterization of Korotkoff Sounds Using Joint and Frequency Analysis". IOP- PM -25 -107, 2004. DOI: 10.1088/0967-3334/25/1/010
  20. E. O'Brein, et al. "Working Group on Blood Pressure Monitoring of the European society of hypertension International Protocol for validation of blood pressure measuring devices in adults," Blood Pressure Monitoring, vol. 7: 3-17, 2002. https://doi.org/10.1097/00126097-200202000-00002
  21. O'Brien E, Atkins N, Stergiou G, Karpettas N, Parati G, Asmar R, et al. "European Society of Hypertension International Protocol revision 2010 for the validation of blood pressure measuring devices in adults," Blood Press Monit, 15:23-38, 2010. DOI: 10.1097/MBP.0b013e3283360e98.