Abstract
The authors use photoelectric plethysmography to determine the external occlusion pressure for blood vessels in human tissue in vivo. Three wavelengths are employed; 950 nm (infra-red), 640 nm (red) and 583 nm (yellow). Each probe is applied in turn to one finger of each subject. Pressure is applied, using a neonatal blood pressure cuff, to the finger via the probe. This pressure is increased linearly to 20 kPa (150 mmHg) over 15 s and then decreased linearly to zero over 15 s. The pressure at which perfusion returns is obtained for four repeat measurements at each wavelength. The mean (±standard deviation) occlusion pressures for all 13 subjects investigated are 7.1(±1.9) kPa for infra-red, 6.3(±1.7) kPa for red and 5.8(±1.8) kPa for yellow. The pressure is 0.79(±0.83) kPa lower for red compared with infra-red (P<0.01), 0.54(±0.60) kPa lower for yellow compared with red (P<0.002) and 1.3(±1.0) kPa lower for yellow compared with infra-red (P<0.005). The reduced penetration of shorter optical wavelengths can be used to detect the lower occlusion pressures of the smaller blood vessels nearer the skin surface.
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References
Cui, W., Ostrander, L. E., andLee, B. Y. (1990): ‘In vivo reflectance of blood and tissue as a function of light wavelength’,IEEE Trans. Biomed. Eng.,37, pp. 632–639
Giltvedt, J., Sira, A., andHelme, P. (1984): ‘Pulsed multifrequency photoplethysmograph’,Med. Biol. Eng. Comput.,22, pp. 212–215
Gush, R. J., andKing, T. A. (1991): ‘Discrimination of capillary and arterio-venular blood flow in skin by laser Doppler flowmetry’,Med. Biol. Eng. Comput.,29, pp. 387–392
Hales, J. R. S., Roberts, R. G. D., Westerman, R. A., Stephens, F. R. N., andFawcett, A. A. (1993): ‘Evidence for skin microvascular compartmentalization by laser-Doppler and photoplethysmographic techniques’,Int. J. Microcirc. Clin. Exp.,12, pp. 99–104
Holstein, P., Nielsen, P. E., Lund, P., Gyntelberg, F., andPoulsen, H. L. (1980): ‘Skin perfusion pressure on the legs measured as the external pressure required for skin reddening after blanching: a photo-electric technique compared to isotope washout’,Scand. J. Clin. Lab. Invest.,40, pp. 535–543
Malvezzi, L., Castronuovo, J. J., Swayne, L. C., Cone, D., andTrivino, J. Z. (1992): ‘The correlation between three methods of skin perfusion pressure measurement: radionuclide washout, laser Doppler flow, and photoplethysmography’,J. Vasc. Surg.,15, pp. 823–829
O'Dea, K. (1993): ‘Prevalence of pressure damage in hospital patients in the UK’,J. Wound. Care.,2, pp. 221–225
Ugnell, H., andOberg, P. A. (1995): ‘The time-variable photo-plethysmographic signal; dependence of the heart synchronous signal on wavelength and sample volume’,Med. Eng. Phys.,17, pp. 571–578
van den Broek, T. A. A., Dwars, B. J., Rauwerda, J. A., andBakker, F. C. (1988): ‘Photoplethysmographic selection of amputation level in peripheral vascular disease’,J. Vasc. Surg.,8, pp. 10–13
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Murray, A., Marjanovic, D. Optical assessment of recovery of tissue blood supply after removal of externally applied pressure. Med. Biol. Eng. Comput. 35, 425–427 (1997). https://doi.org/10.1007/BF02534102
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DOI: https://doi.org/10.1007/BF02534102