Development of a Two-Channel Simultaneous Photoplethysmography Recording System

Kim Soon Chong, Kok Beng Gan, Mohd. Ali Mohd. Alauddin


Multi-site photoplethysmograph  (PPG) recording enables researchers to study the vascular and hemodynamic  properties of human subjects. Currently, there  is  no  commercial  system  available  in  the  market  to  perform  either  one channel or multi-channel PPG recording. PPG is an optoelectronic technique that measures  changes  in  blood  volume  associated  with  cardiac  contraction.  The measurements  can  be  obtained  from  fingertips,  ear  lobes  and toes  due  to  their low absorption and high degree of vasculature. The main objective of this project is to develop a two-channel simultaneous PPG recording system to acquire PPG signals  from  two  different  physiological  sites  using  a  Nellcor  equivalent  PPG probe.  MATLAB  software  was  used  during  the  development  phase  to  ensure rapid prototyping. The experiment results show that there was no inter -channel delay in the developed two-channel PPG system. Our preliminary results show that the delays between the left and the right arm were from 4 to 12 ms in three healthy random subjects. The system is portable, powered by universal serial bus (USB) and allows the user to do the PPG data acquisition in a clinical setting.

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Zahedi, E., Chellappan, K., Mohd Alauddin, M.A. & Singh, H, Analysis of the Effect of Ageing on Rising Edge Characteristics of the Photoplethysmogram using a Modified Windkessel Model, Cardiovascular Engineering, 7, pp. 172-181, 2009.

Allen, J., Overbeck, K., Stansby, G. & Murray, A, Photoplethysmography Assessments in Cardiovascular Disease, Measurement Control, 39, pp. 80-83, 2006.

Allen, J., Oates, C.P., Lees, T.A. & Murray, A., Photoplethysmography Detection of Lower Limb Peripheral Arterial Occlusive Disease: A Comparison of Pulse Timing, Amplitude and Shape Characteristics, Physiological Measurement, 26, pp. 811-821, 2005.

Allen, J. & Murray, A., Age-Related Changes in Peripheral Pulse Shape Characteristics at Various Body Sites, Physiological Measurement, 24, pp. 297-307, 2003.

World Health Organization, Cause of death in Malaysia, Geneva: WHO, 2009.

Laurent, S., Boutouyrie, P., Asmar, R., Gautier, I., Laloux, B., Guize, L. Ducimetiere, P. & Benetos, A., Aortic Stiffness is An Independent Predictor of All-Cause and Cardiovascular Mortality in Hypertensive Patients, Hypertension, 37, pp.1236-1241, 2011.

Oliver, J.J. & Webb, D.J., Noninvasive Assessment of Arterial Stiffness and Risk of Atherosclerotic Events, Arterioscler Thromb Vasc. Biol., 23, pp. 554-566, 2003.

Bronzino, J.D, The Biomedical Engineering Handbook, 1, Florida: CRC Press LLC, 2000.

Bhattacharya, P.P., Kanjilal & Muralidhar, V., Analysis and Characterization of Photoplethysmographic Signal, IEEE Transsaction of Biomedical Engineering, 48, pp. 5-11, 2001.

Allen, J. & Murray, A., Variability of Photoplethysmography Peripheral Pulse Measurements at The Ears, Thumbs and Toes, IEEE Proceeding Science and Technology, 147(6), pp. 403-407, 2000.

Allen, J., Photoplethysmography and Its Application in Clinical Physiological Measurement, Physiological Measurement, 28, R1, 2007.

Allen, J. & Murray, A., Similarity in Bilateral PhotoplethysmographicPeripheral Pulse Wave Characteristics at The Ears Thumbs and Toes, Physiological Measurement, 21, pp. 369-377, 2000.

Spigulis, J., Erts, R., & Ozols, M., Optical Multi-Channel Monitoring of Skin Blood Pulsations for Cardiovascular Assessment, SPIE Proc Advanced Biomedical and Clinical Diagnostic Systems, 5318, p.133-139, 2004.

Erts, R., Spigulis, J., Kukulis, I., & Ozols, M., Bilateral Photoplethysmography Studies of The Leg Arterial Stenosis, Physiological Measurement, 26, pp. 865-874, 2005.

Zahedi, E. & Mohd. Ali, M.A., Dual-Channel Photoplethysmography Synchronization Using A Barker Sequence, Conference Procedings IEEE Engineering in Medicine and Biology Society, 2, pp. 1952-1955, 2005.

Spigulis, J., Venckus, G. & Ozols, M., Optical Sensing for Early Cardiovascular Diagnostic, Proceedings SPIE, 3911, pp. 27-31, 2000.



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