Abstract
New techniques for determining the hematocrit (Hct) and oxygen saturation (SO2) of whole blood from backscattered light measurements are described. First, theoretical and experimental results are presented which show that the empirical linear relationship between SO2and the infrared-red backscattered light intensity ratio on which previous instruments have been based is an inadequate description primarily because it does not account for the strong effects of Hct and transducer geometry. Then it is shown that the ratio of backscattered intensities from two appropriately positioned infrared sources can be plotted against the infrared-red intensity ratio to produce a family of calibration curves from which SO2and Hct can be independently determined. Finally, a practical implementation of an oximetry system which employs a microelectronic catheter-tip optical sensor and a microprocessor-based signal processor is proposed.
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References
Polanyi, M.L. and R.M. Hehir. New reflection oximeter.Rev. Scient. Instrum., 31:401–403, 1960.
Harrison, D.C., N.S. Kapany, H.A. Miller, N. Silbertrust, W.L. Henry, and R.P. Drake. Fiber optics for continuous in vivo monitoring of oxygen saturation.Am. Heart J., 71(6):766–774, 1966.
Johnson, C.C., R.D. Palm, D.C. Stewart, and W.E. Martin. A solid state fiberoptic oximeter.J. Assoc. Advanc. Med. Instrumentation. 5:77–83, 1978.
Landsman, M.L., N. Knap, G. Kwant, G.A. Mook, and W.G. Zijlstra. A fiberoptic reflection oximeter.Plugers Archives. 373:273–282, 1978.
Mook, G.A., P. Osypka, R.E. Sturm, and E.H. Wood. Fibre optic reflection photometry on blood.Cardiovasc. Res. 2:199–209, 1968.
Cole, J.S., W.E. Martin, P.W. Cheung, and C.C. Johnson. Clinical studies with a solid state fiberoptic oximeter.Am. J. Cardiology. 29:383–388, 1972.
Martin, W.E., P.W. Cheung, C.C. Johnson, and K.C. Wong. Oxygen saturation.Anesthesia and Analgesia Current Research. 52(5):784–793, 1973.
Woodroof, E.A., and S. Koorajian. In vitro evaluation of an in vivo fiber-optic oximeter.J. Assoc. Advanc. Med. Instrumentation. 7:287–292, 1973.
Cheung, P.W. Effects of blood physiological variations on optical scattering and fiberoptic oximetry. Ph. D. thesis. Dept. of Elect. Eng., Univ. of Wash., 1973.
Schweiss, J.F.. Use of continuous SvO2 intra and postoperatively in managing the hemodynamics of cardiac surgery patients. In.Continuous Measurement of Blood Oxygen Saturation in the High Risk Patient, Vol. I edited by J.F. Schweiss, St. Louis, Missouri: Society of Critical Care Medicine, 1982, pp. 81–111.
Reynolds, L.O. Optical diffuse reflectance and transmittance from an anisotropically scattering finite blood medium. Ph.D. thesis, Dept. of Elect. Eng., Univ. of Wash., 1975.
Reynolds, L.O., C. Johnson, and A. Ishimaru. Diffuse reflectance from a finite blood medium: applications to the modeling of fiber optic catheters.Applied Optics. 15(9):2059–2067, 1976.
Bohren, C.F. and D.R. Huffman.Absorption and Scattering of Light by Small Particles. New York: Wiley, 1983, 477–482.
Schmitt, J.M., F.G. Mihm, J. Shott, and J.D. Meindl. Implantable telemetry for measurement of O2 saturation. InProc. of 6th Annual Conf. IEEE Eng. in Med. and Biology. Los Angeles, CA, Sept. 1984, 703–704.
Bowman, L., J.M. Schmitt, and J.D. Meindl. Electrical contact to implantable integrated sensors by CO2 laser-drilled vias through glass.Workshop on Micromachining and Micropackaging of Transducers. Cleveland, OH, Nov. 1984.
Van Assendelft, O.Spectrophotometry of Hemoglobin Derivatives, Assen, the Netherlands: Royal Van Gorcum Ltd., 1970.
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This work was supported in part by NIH Grant 5P50GM17940.
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Schmitt, J.M., Mihm, F.G. & Meindl, J.D. New methods for whole blood oximetry. Ann Biomed Eng 14, 35–52 (1986). https://doi.org/10.1007/BF02364647
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DOI: https://doi.org/10.1007/BF02364647