Document Type : Full Research Paper

Authors

1 PhD student, Department of Biomedical Engineering, University of Wisconsin-Madison

2 Associate Professor, Electrical Engineering Department, Faculty of Biomedical Engineering, Sharif University of Technology

10.22041/ijbme.2013.13132

Abstract

The photoplethysmogram (PPG) is a low cost and ubiquitous signal and has always had a great significance in cardiovascular parameter identification such as arterial dilation due to a stimulus. The PPG is generally recorded from the fingertip which is affected by the auto-regulation mechanism (ARM), preventing the results to be well correlated with standard methods based on imaging the brachial or radial artery.  Based on the fact that the ARM has no effect on conduit arteries, the correlation between fingertip and radial artery PPG is investigated in this work. A custom made probe is fabricated using an array of photodiodes and a 960 nm LED for recording the wrist photoplethysmogram (PPG). The design is based on Monte-Carlo simulation of light propagation in tissues. Two series of experiments were carried-out: normal breathing and deep breathing. In both experiments, index finger and wrist PPG were simultaneously recorded. In the first series of experiments, signals from 9 subjects were recorded and the correlation coefficient for the raw signals (AC+DC), the AC and DC components of wrist and finger PPG were 62.5% ± 12.1%, 91.2% ± 6.9% and 61% ± 13.4% respectively. In the second series of experiment (deep breathing), signals from 6 subjects were recorded and the correlation coefficient for the raw signals (AC+DC), the AC and DC components were 89.7% ± 5.9%, 93.7% ± 3.3% and 89.9% ± 5.9% respectively. These results show that under normal breathing conditions, only the AC components of the PPG signals are highly correlated. When respiration becomes the dominant effect, both AC and DC parts become highly correlated.

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Main Subjects

[1]     Allen J., Photoplethysmography and its application in clinical physiological measurement; Physiol. Meas., 2007; 28: 1-39.
[2]     Pedrotti F.L., Pedrotti L.S., Introduction to optics; PrenticeHall, 2 edition, 1993.
[3]     Dorlas J.C., Nijboer J.A., Photo-electric plethysmography as a monitoring device in anaesthesia; Br. J. Anaesth., 1985; 57: 524-530.
[4]     Larsen P.D., Harty M., Thiruchelvam M., Galletly D.C., Spectral analysis of AC and DC components of the pulse photoplethysmograph at rest and during induction of anaesthesia; Int. J. Clin. Monit. Cornput., 1997; 14: 89-95.
[5]      Allen J., Murray A., Modeling the relationship between peripheral      blood pressure and blood volume pulses using linear and neural network system identification techniques; Physiol. Meas. London, 1999; 20: 287-301.
[6]     Lopez-Beltran E.A., Blackshear P.L., Finkelstein S.M., Cohn J.N., Non-invasive studies of peripheral vascular compliance using a non-occluding photoplethysmographic method; Med. BioI. Eng. Comput., 1998; 36: 748-53.
[7]     Cox D.A., Vita J.A., Treasure C.B., Fish R.D., Alexander R.W., Ganz P., Selwyn A.P., Atherosclerosis impairs flow-mediated dilation of coronary arteries in humans; Circulation 80, 1989: 458-465.
[8]      Low P.A., Neumann C., Dyck P.J., Fealey R.D.,  Tuck R., Evaluation of skin vasomotor reflexes using Doppler velocimetry; Mayo Clin. Proc. 1983; 58: 583–586.
[9]      Wallin B.G., Batelsson K., Kienbaum P., Karlsson T., Gazelius B., Elam M., Two neural mechanisms for respiration induced cutaneousvasodilatation in humans?; J. Physiol. (London), 1998; 513(2): 559– 569.
[10]  Rauh R., Posfay A., Muck-Weynmann M., Quantification ofinspiratory-induced vasoconstrictive episodes: a comparison of laserDoppler fluxmetry and photoplethysmography; Clin. Physiol. Funct.Imag., 2003; 23: 344–348.
[11] Nitzan M., Faib I., Friedman H., Respiration-induced changes in tissue blood volume distal to occluded artery, measured by photoplethysmography; J. Biomed. Opt. 0001; 11(4):040506-040506-3.
[12] Mayrovitz H.N., Groseclose E.E., Inspira-tion-induced vasoconstrictive responses in dominant versus non-dominant hand; Clinical Physiology and Functional Imaging, 2005; 25: 69-77. doi:10.1111/j.1475-097X.2004.00592.
[13]  Nitzan M., De Boer H., Turivnenko S., et al. Power spectrum analysis of the spontaneous fluctuations in the photoplethysmographic signal; Journal of Basic and Clinical Physiology and Pharmacology, 1994; 5: 269-276. doi:10.1515/JBCPP.1994.5.3-4.269
[14] Coleman S.S., Anson B.J., Arterial patterns in the hand based upon a study of 650 specimens; Surg Gynecol Obstet., 1961; No. 113: 409-424.
[15] Clemente C.D., Anatomy: A regional atlas of the human body; Urban & Schwarzenberg, 3rd edition, 1986.
[16]  Parati G., Casadei R., Groppelli A., Rienzo M.D.,  Mancia G., Comparison of finger and intra-arterial blood pressure monitoring at rest and during laboratory testing; Hypertension, 1989; No. 13: 647-655.
[17]  Langewouters G.J., Zwart A., Busse R., Wesseling K.H., Pressure-diameter relationships of segments of human finger arteries; Clin Phys Physiol Meas, 1986; 7(1): 43–56.
[18] Reisner A., Shaltis P.A., McCombie D., Asada H.H., Utility of the photoplethysmogram in circulatory monitoring; Anesthesiology, 2008; 108(5): 950-958.
[19] Tuchin V.V., Tissue optics: light scattering methods and instruments for medical diagnosis; SPIE, 2nd ed., 2007.
[20] Jellinek H., Krenn H., Oczenski W., Veit F., Schwarz S., Fitzgerald R.D., Influence of positiveairway pressure on the pressure gradient for venous return in humans; J. Appl. Physiol., 2000; 88: 926–932.
[21] Geun E., Heo H., Nam K.C., Huh Y., Measurement site and applied pressure consideration in wrist photoplethysmography; The 23rd International Technical Conference on CircuitsSystems Computers and Communications, 2008: 1129-1132.
[22] Park C., Sohn J., kim J., Choi H., Artifact-resistant design of a wrist-type heart rate monitoring device; 11th International Conference on Advanced Communication Technology, 2009.
[23] Shariati N.H., Zahedi E., Jajai H.M., Classification of vascular function in upper limb using bilateral photoplethysmographic signals; Physiol. Meas., 2008; 29: 365–374.
[24] Zahedi E., Jaafar R., Mohd Ali M.A., Mohamed A.L., Maskon O., Finger photoplethysmogram pulse amplitude changes induced by flow-mediated dilation; Physiol. Meas., 2008; 29: 625–637