Annals of Biomedical Engineering

, Volume 22, Issue 1, pp 88–96 | Cite as

Theory of the oscillometric maximum and the systolic and diastolic detection ratios

  • G. Drzewiecki
  • R. Hood
  • H. Apple
Article

Abstract

It is proposed that the maximum in cuff pressure oscillations during oscillometry is due to the buckling of the brachial artery under a cuff. This theory is investigated by means of a mathematical model of oscillometry that includes the mechanics of the occlusive arm cuff, the arterial pressure pulse waveform, and the mechanics of the brachial artery. A numerical solution is provided for the oscillations in cuff pressure for one cycle of cuff inflation and deflation. The buckling pressure is determined from actual arterial data and the von Mises buckling criteria. The buckling of an artery under a cuff occurs near — 2 to 0 mm Hg transmural pressure. This effect corresponds with a maximum arterial compliance and maximum cuff pressure oscillations when cuff pressure is nearly equal to mean arterial pressure (MAP), in support of the suggested theory. The model was also found to demonstrate the basic characteristics of experimental oscillometry, such as an increasing and decreasing amplitude in oscillations as cuff pressure decreases, the oscillations that occur when cuff pressure is above systolic pressure, maximum oscillation amplitudes in the range of 1 to 4 mm Hg, and an oscillatory maximum at cuff pressure equal to MAP. These findings support the case that the model is representative of oscillometry. Finally, the model predicted values for the systolic and diastolic detection ratios of 0.593 and 0.717, respectively, similar to those found empirically. These ratios alter with blood pressure, but the tightness of the cuff wrap did not change their value.

Keywords

Oscillometry Blood pressure measurement Arterial mechanics Occlusive cuff Mathematical modeling 

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References

  1. 1.
    Alexander, H.; Cohen, M.; Steinfeld, L. Criteria in the choice of an occluding cuff for the indirect measurement of blood pressure. Med. Biol. Eng. Comput. 15:2–10; 1977.PubMedGoogle Scholar
  2. 2.
    Brower, R.W.; Noordergraaf, A. Theory of steady flow in collapsible tubes and veins. In: Baan, J.; Noordergraaf, A.; Raines, J. eds. Cardiovascular system dynamics. Cambridge, MA: Cambridge, 1978: pp. 256–265.Google Scholar
  3. 3.
    Drzewiecki, G.M.; Rabbany, S.Y.; Melbin, J.; Noordergraaf, A. Generalization of the transmural pressure-area relation for the femoral artery. Proc. 7th Ann. Conf. EMBS/IEEE, Chicago, IL; 1985: pp. 507–510.Google Scholar
  4. 4.
    Drzewiecki, G.M.; Moubarak, I.F. Transmural pressurearea relation for veins and arteries. Proc. 14th Ann. Northeast Bioeng. Conf., Univ. New Hampshire; 1988: pp. 269–272.Google Scholar
  5. 5.
    Drzewiecki, G.M.; Melbin, J.; Noordergraaf, A. The Korotkoff sound. Ann. Biomedical Eng. 17:325–359; 1989.Google Scholar
  6. 6.
    Drzewiecki, G.M.; Karam, E.; Bansal, V.; Hood, R.; Apple, H. Mechanics of the occlusive arm cuff and its application as a volume sensor. IEEE Trans. Biomed. Eng. 40:704–708; 1993.CrossRefPubMedGoogle Scholar
  7. 7.
    Flaherty, J.E.; Keller, J.B.; Rubinow, S.I. Post buckling behavior of elastic tubes and rings with opposite sides in contact. SIAM J. Applied Math. 23:446–455; 1972.Google Scholar
  8. 8.
    Forster, F.K.; Turney, D. Oscillometric determination of diastolic, mean, and systolic blood pressure—a numerical model. J. Biomech. Eng. 108:359–364; 1986.PubMedGoogle Scholar
  9. 9.
    Fung, Y.C. Biodynamics—circulation. New York: Springer-Verlag; 1984.Google Scholar
  10. 10.
    Geddes, L.A.; M.L.; Voelz, M.; Combs, C.; Reiner, D. Characterization of the oscillometric method for measuring indirect blood pressure. Ann. Biomed. Eng. 10:271–280; 1983.Google Scholar
  11. 11.
    Kresch, E. Compliance of flexible tubes. J. Biomech. 12: 825–839; 1979.CrossRefPubMedGoogle Scholar
  12. 12.
    Link, W.T. Techniques for obtaining information associated with an individual's blood pressure including specifically a stat mode technique. U.S. Patent #4,664, 126; 1987.Google Scholar
  13. 13.
    Marey, E.J. La Methode Graphique dans les Sciences Experimentales et principalement en Physiologie et en Medicine. Paris: Masson; 1885.Google Scholar
  14. 14.
    Mauck, G.W.; Smith, C.R.; Geddes, L.A.; Bourland, J.D. The meaning of the point of maximum oscillations in cuff pressure in the indirect measurement of blood pressure: II. J. Biomech. Eng. 102:28; 1980.PubMedGoogle Scholar
  15. 15.
    Moreno, A.H.; Katz, A.I.; Gold, L.D.; Reddy, R.V. Mechanics of the distension of dog veins and other very thinwalled tubular structures. Circ. Res. 27:1069–1079; 1970.PubMedGoogle Scholar
  16. 16.
    Noordergraaf, A. Circulatory system dynamics. New York: Academic Press; 1978.Google Scholar
  17. 17.
    Pedley, T.J. Flow in collapsible tubes. In: The fluid mechanics of large blood vessels. Oxford: Cambridge University Press; Chap. 6, pp. 301–368, 1980.Google Scholar
  18. 18.
    Ramsey III, M. Noninvasive blood pressure determination of mean arterial pressure. Med. Biol. Eng. Comp. 17:11–18; 1979.Google Scholar
  19. 19.
    Shapiro, A.H. Steady flow in collapsible tubes. Trans. ASME (ser. K.) J. Biomech. Eng. 99:126–147; 1977.Google Scholar
  20. 20.
    von Mises, R. Der kritische aussendruck zylindrischer Rohre. Ver. Deut. Ing. Z. 58:750–755; 1914.Google Scholar

Copyright information

© Biomedical Engineering Society 1994

Authors and Affiliations

  • G. Drzewiecki
    • 1
  • R. Hood
    • 2
  • H. Apple
    • 2
  1. 1.Department of Biomedical Engineering, RutgersThe State University of New JerseyPiscataway
  2. 2.Critikon, Inc.Tampa

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