Skip to content
Licensed Unlicensed Requires Authentication Published by Oldenbourg Wissenschaftsverlag March 27, 2018

Development of bioimpedance sensing device for wearable monitoring of the aortic blood pressure curve

Entwicklung eines Bioimpedanz-Messgerätes für die mobile Erfassung des aortalen Blutdruck
H. Kõiv, M. Rist and M. Min
From the journal tm - Technisches Messen


Wearable devices that monitor our vital signs have been gaining more importance with each year. Non-invasive, continuous, accurate and precise blood pressure assessment method integrated in a wearable is a multidisciplinary challenge. This work presents an electrical bioimpedance (EBI) unit for multi-frequency measurements on pulsating artery for central aortic pressure (CAP) estimation. The developed device provides low complexity in the electronics design with a frequency range between 1 kHz and 200 kHz. It is able to register the impedance of blood vessel volume change simultaneously at different locations. Experiments were carried out in vivo by using the four-electrode configuration on human thorax, axillary artery and radial artery. Preliminary results show the applicability of the proposed impedance spectroscopy system to measure blood vessel volume changes. The impedance data can be later interpreted into the aortic blood pressure wave by using a generalized transfer function. In addition, experimental test-phantom and electrode design are introduced for testing purposes of the impedance system.


Tragbare Messgeräte, welche unsere Vitalfunktionen aufzeichnen, gewinnen von Jahr zu Jahr an Bedeutung. Nicht-invasive, kontinuierliche, präzise und genaue Blutdruckmessverfahren, welche in einem tragbaren System realisiert werden, sind eine multidisziplinäre Herausforderung. Diese Arbeit präsentiert ein Messgerät, welches die elektrische Bioimpedanz (EBI) einer pulsierenden Arterie misst, um den zentralen aortalen Blutdruck (CAP) zu bestimmen. Das entwickelte Gerät basiert auf einem einfachen elektrischen Design und deckt einen Frequenzbereich zwischen 1 kHz und 200 kHz ab. Es ermöglicht die simultane Erfassung der Volumenänderung einer Arterie an mehreren Messpunkten. Die Experimente wurden in vivo mit einer Konfiguration aus vier Elektroden an einem menschlichen Thorax, Arteria axillaris und der Arteria radialis durchgeführt. Zwischenergebnisse zeigen die grundsätzliche Anwendbarkeit der Impedanzspektroskopie, welche die Volumenänderung der Blutgefäße erfasst. Die Daten der Impedanzmessung werden mittels einer generalisierenden Transferfunktion in arterielle Blutdruckkurven umgewandelt. Des Weiteren zeigen wir ein experimentelles Phantom und das Elektrodendesign für Testzwecke des Bioimpedanzsystems.

Funding source: Eesti Teadusagentuur

Award Identifier / Grant number: IUT19-11

Funding statement: The research was supported by Eesti Teadusagentuur (grant IUT19-11) and the Centre of ICT Research Excellence EXCITE in collaboration with the Horizon 2020 Framework Programme FLAG-ERA JTC 2016 HESN project CONVERGENCE.


1. ESC, “European cardiovascular disease statistics 2017 edition, ” Tech. Rep., 2017.Search in Google Scholar

2. “High Blood Pressure (Hypertension) Information |,”, 2017 [Online]. Available: [Accessed: 10-Sep-2017].Search in Google Scholar

3. C. M. McEniery, J. R. Cockcroft, M. J. Roman, S. S. Franklin and I. B. Wilkinson, “Central blood pressure: current evidence and clinical importance,” Eur. Heart J., vol. 35, no. 26, pp. 1719–1725, Jul. 2014.10.1093/eurheartj/eht565Search in Google Scholar

4. B. Freeman and J. Berger, Anesthesiology Core Review: Part 2, Chapter 1: Invasive Arterial Blood Pressure Monitoring, Cenveo® Publisher Services, 2016.Search in Google Scholar

5. A. Avolio, M. Butlin, and A. Walsh, “Arterial blood pressure measurement and pulse wave analysis – their role in enhancing cardiovascular assessment,” Physiological Measurement, vol. 31, no. 1, pp. R1–R47, 2009.10.1088/0967-3334/31/1/R01Search in Google Scholar

6. L. Nainggolan, “New Devices to Measure Central Aortic Pressure: Interesting But Premature,” Medscape, 2011.Search in Google Scholar

7. S. DeLoach and R. Townsend, “Vascular Stiffness: Its Measurement and Significance for Epidemiologic and Outcome Studies,” Clinical Journal of the American Society of Nephrology, vol. 3, no. 1, pp. 184–192, 2008.10.2215/CJN.03340807Search in Google Scholar

8. A. Krivoshei, J. Lamp, M. Min, T. Uuetoa, H. Uuetoa and P. Annus, “Non-invasive method for the aortic blood pressure waveform estimation using the measured radial EBI,” Journal of Physics: Conference Series, vol. 434, 012048, 2013.10.1088/1742-6596/434/1/012048Search in Google Scholar

9. “Home – HealthSTATS,”, 2017 [Online]. Available: [Accessed: 3-Feb-2017].Search in Google Scholar

10. “Tensys Medical – cetrixtablets,” cetrixtablets, 2018 [Online]. Available: [Accessed: 10-Jan-2018].Search in Google Scholar

11. O. monitor, “Omron HEM-9000AI blood pressure mon,” Medi-Shop, 2018 [Online]. Available: [Accessed: 07-Jan-2018].Search in Google Scholar

12. “The intelligent pressure monitoring system, CODAN, Xtrans, Brochure” [Online]. Available: [Accessed: 3-Nov-2017].Search in Google Scholar

13. A. Krivošei, H. Uuetoa, M. Min, P. Annus, T. Uuetoa and J. Lamp, “Adaptive Algorithm for Cardiac Period Normalization in Time,” in Book of Abstracts: 16th International Conference on Electrical Bio-Impedance (ICEBI) and the 17th Conference on Electrical Impedance Tomography (EIT) 2016, pp. 66, 2016.Search in Google Scholar

14. A. Krivošei, M. Min, P. Annus, H. Kõiv, A. Aabloo and T. Uuetoa, “Analysis of Instantaneous Cardiac EBI Signal Variability over the Heart Cycle(s): Non-Linear Time-Scale Approach,” in Joint Conference of European Medical and Biological Engineering Conference (EMBEC) and Nordic-Baltic Conference on Biomedical Engineering and Medical Physics (NBC) (EMBEC2017), Tampere, Finland, pp. 940–943, 2017.10.1007/978-981-10-5122-7_235Search in Google Scholar

15. A. Cömert and J. Hyttinen, “Investigating the possible effect of electrode support structure on motion artifact in wearable bioelectric signal monitoring,” BioMedical Engineering OnLine, vol. 14, no. 1, 2015.10.1186/s12938-015-0044-2Search in Google Scholar

16. M. Min, A. Krivošei, P. Annus, H. Kõiv, T. Uuetoa and J. Lamp, “Bioimpedance sensing – a viable alternative for tonometry in non-invasive assessment of central blood pressure”, in Proc. 12th Annual IEEE International Symposium on Medical Measurements and Applications (MeMeA, Mayo Clinic, Rochester, MN, USA), IEEE, pp. 373–378, 2017, DOI:10.1109/MeMeA.2017.7985905.Search in Google Scholar

17. A. T. Mobashsher and A.M. Abbosh, “Artificial Human Phantoms: Human Proxy in Testing Microwave Apparatuses That Have Electromagnetic Interaction with the Human Body,” IEEE Microwave Magazine, vol. 16, no. 6, 2015.10.1109/MMM.2015.2419772Search in Google Scholar

18. T. K. Bera, “Bioelectrical Impedance Methods for Noninvasive Health Monitoring: A review,” Journal of Medical Engineering, vol. 2014, Article ID 381251, 28 pages, 2014.10.1155/2014/381251Search in Google Scholar

19. C. Gabriel, S. Gabriel and E. Corthout, “The dielectric properties of biological tissues: I. Literature survey,” Physics in Medicine and Biology, vol. 41, no. 11, pp. 2231–2249, 1996.10.1088/0031-9155/41/11/001Search in Google Scholar

20. A. Pinto, P. Bertemes-Filho and A. Paterno, “Gelatin: a skin phantom for bioimpedance spectroscopy,” Biomedical Physics & Engineering Express, vol. 1, no. 3, 035001, 2015.10.1007/978-3-319-13117-7_47Search in Google Scholar

21. A. K. Dabrowska, G.-M. Rotaru, S. Derler, F. Spano, M. Camenzind, S. Annaheim, R. Stämpfli, M. Schmid and R. M. Rossi, “Materials used to simulate physical properties of human skin,” Skin Research and Technology, vol. 22, pp. 3–14, 2016.10.1111/srt.12235Search in Google Scholar

22. A. Katihabwa, W. Wang, Y. Jiang, X. Zhao, Y. Lu and L. Zhang, “Multi-walled carbon nanotubes/silicone rubber nanocomposites prepared by high shear mechanical mixing,” Journal of Reinforced Plastics and Composites, vol. 30, no. 12, pp. 1007–1014, 2011.10.1177/0731684410394008Search in Google Scholar

23. A. Saleem, L. Frormann and A. Soever, “Fabrication of Extrinsically Conductive Silicone Rubbers with High Elasticity and Analysis of Their Mechanical and Electrical Characteristics,” Polymers, vol. 2, no. 3, pp. 200–210, 2010.10.3390/polym2030200Search in Google Scholar

24. B. Mensah, H. Kim, J. Lee, S. Arepalli and C. Nah, “Carbon nanotube-reinforced elastomeric nanocomposites: a review,” International Journal of Smart and Nano Materials, vol. 6, no. 4, pp. 211–238, 2015.10.1080/19475411.2015.1121632Search in Google Scholar

25. S. Grimnes and Ø. G. Martinsen, Bioimpedance and bioelectricity basics, Academic Press, 2000.10.1016/B978-012303260-7/50009-5Search in Google Scholar

26. R. Land, P. Annus, M. Min, et al.Method and device for broadband analysis of systems and substances. European Patent Application EP2565654A2, Bulletin 2013/10; US Application US2013054178A1, publ. Feb. 28, 2013. – Patent.Search in Google Scholar

27. M. Rist, M. Reidla, M. Min, T. Parve, O. Märtens and R. Land, “TMS320F28069-based impedance spectroscopy with binary excitation,” in EDERC 2012 Proceedings of the 5th European DSP in Education & Research Conference, pp. 217–220, 2012.10.1109/EDERC.2012.6532258Search in Google Scholar

28. S. Halonen, K. Annala, J. Kari, S. Jokinen, A. Lumme, K. Kronström and A. Yli-Hankala, “Detection of spine structures with Bioimpedance Probe (BIP),” Journal of Clinical Monitoring and Computing, pp. 1–8, 2016.10.1007/s10877-016-9915-8Search in Google Scholar

29. IEC 60601 – TC 62/SC 62A – Common aspects of electrical equipment used in medical practice. International Standard, Edition 1.0, 2015.Search in Google Scholar

30. J. Schneider, M. Schroth, M. Holzhey, T. Blocher and W. Stork, “An approach to improve impedance plethysmography on the wrist by using adaptive feedback control,” in 2017 IEEE Sensors Applications Symposium (SAS), 2017.10.1109/SAS.2017.7894063Search in Google Scholar

31. J. Wang, W. Hu, T. Kao, C. Liu and S. Lin, “Development of forearm impedance plethysmography for the minimally invasive monitoring of cardiac pumping function,” Journal of Biomedical Science and Engineering, vol. 04, no. 02, pp. 122–129, 2011.10.4236/jbise.2011.42018Search in Google Scholar

32. J. Xu, X. Gao, A. Lee, S. Yamada, E. Yavari, V. Lubecke and O. Boric-Lubecke, “Wrist-worn heartbeat monitoring system based on bio-impedance analysis,” in 2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2016.10.1109/EMBC.2016.7592167Search in Google Scholar

33. B. Han, Y. Xu and F. Dong, “Design of current source for multi-frequency simultaneous electrical impedance tomography,” Review of Scientific Instruments, vol. 88, no. 9, 094709, 2017.10.1063/1.5004185Search in Google Scholar

34. B. Sanchez, E. Louarroudi and R. Pintelon, “Time-invariant measurement of time-varying bioimpedance using vector impedance analysis,” Physiological Measurement, vol. 36, no. 3, pp. 595–620, 2015.10.1088/0967-3334/36/3/595Search in Google Scholar

Received: 2017-9-15
Revised: 2018-1-20
Accepted: 2018-3-18
Published Online: 2018-3-27
Published in Print: 2018-5-25

© 2018 Walter de Gruyter GmbH, Berlin/Boston