Cardiac output measurements. A review of current techniques and research


Cardiac output is the volume of blood ejected by the heart per unit time. It is a useful measurement in that it can be used to evaluate overall cardiac status in both critically ill patients and patients with suspected cardiovascular disease. An ideal cardiac output measurement system would have automated continuous output capability, be minimally invasive, accurate, fast, small, low cost and clinically adaptable. This paper presents a theoretical and practical description of the variety of clinical techniques in use today and lists their advantages and shortcomings with respect to the ideal system. Included are the Fick method, indicator dilution techniques, velocity measurements and transthoracic impedance and combined Doppler ultrasound as noninvasive techniques. In addition, several experimental methods are described along with their desirable features and possible constraints. These include intravascular heating/recording, thermistor tracking of cardiac output, ejection fraction measurements and magnetic susceptability plethysmography.

This is a preview of subscription content, access via your institution.


  1. 1.

    Guyton, A.C.Textbook of Medical Physiology. Philadelphia: Saunders, 1976, pp. 222–235.

    Google Scholar 

  2. 2.

    The Human Body: It's Major Systems and Their Functions. Ethicon, 1975, pp. 17–22.

  3. 3.

    Daily, E. and J. Shroeder.Techniques in Bedside Hemo-dynamic Monitoring. St. Louis: Mosby, 1981, pp. 110–131.

    Google Scholar 

  4. 4.

    Russel, R. and C. Rockly.Hemodynamic Monitoring in a Coronary Intensive Care Unit. Mount Kisco: Futura, 1981, pp. 81–88.

    Google Scholar 

  5. 5.

    Feldman, S.A., J.M. Leigh and J. Spierdijk, eds.Measurements in Anesthesia. Leiden: Leiden University Press, 1974, pp. 144–148.

    Google Scholar 

  6. 6.

    Gravenstein, J.S. and D. Paulus.Monitoring Practice in Clinical Anesthesia. Philadelphia: Lippincott, 1982, pp. 138–142.

    Google Scholar 

  7. 7.

    Webster, J.G., ed.Medical Instrumentation: Application and Design. Boston: Houghton Mifflin, 1978, pp. 385–417.

    Google Scholar 

  8. 8.

    Fick, A. Uber die messung des blutquantums in deu herzventrikeln.Sitz der Physik-Med ges Wurlzberg, 1870, p. 16.

  9. 9.

    Grossman, W., ed.Cardiac Catheterization and Angiography. Philadelphia: Lea & Febiger, 1980, pp. 19–20.

    Google Scholar 

  10. 10.

    Thomasson, B. Cardiac output in normal subjects under standard basal conditions. The repeatability of measurements by the Fick method.Scan. J. Clin. Lab. Invest. 9:365–375, 1957.

    CAS  Google Scholar 

  11. 11.

    Seely, R.D., W.E. Nerlick and D.E. Gregg. A comparison of cardiac output determined by the Fick procedure and a direct method using the rotameter.Circulation 1:1261–1266, 1950.

    PubMed  CAS  Google Scholar 

  12. 12.

    Visscher, M.B. and J.A. Johnson. The Fick principle: Analysis of potential errors in its conventional application.J. Appl. Phys. 5:635–638, 1953.

    CAS  Google Scholar 

  13. 13.

    Stewart, G.N. Researches on the circulation time and on the influences which offset it. IV. The output of the heart.J. Physiol. 22:159–183, 1897.

    PubMed  CAS  Google Scholar 

  14. 14.

    Fox, I.J. History and developmental aspects of the indicator dilution techniques.Circ. Res. 10:381–392, 1962.

    PubMed  CAS  Google Scholar 

  15. 15.

    Zierler, K.L. Theoretical basis of indicator-dilution methods for measuring flow and volume.Circ. Res. 10:393–407, 1962.

    Google Scholar 

  16. 16.

    Hosie, K.F. Thermal-dilution techniques.Circ. Res. 10:491–504, 1962.

    PubMed  CAS  Google Scholar 

  17. 17.

    Trautman, E.D. and R.S. Newbower. The development of indicator-dilution techniques.IEEE Trans. Biomed. Engng BME-31:800–807, 1984.

    Article  CAS  Google Scholar 

  18. 18.

    Reed, J.H., Jr. and E.H. Wood. Use of dichromatic earpiece densitometry for determination of cardiac output.J. Appl. Phys. 23:373–379, 1967.

    Google Scholar 

  19. 19.

    Robinson, P.S., A. Crowther, B.S. Jenkins, M.M. Webb-Peploe and D.J. Goltart. A computerized dichromatic earpiece densitomer for the measurement of cardiac output.Cardiovas. Res. 13:420–426, 1979.

    CAS  Google Scholar 

  20. 20.

    Venkataraman, K., M. DeGuzman, A. Hafeez Khan and L.J. Haywood. Cardiac output measurement: A comparison of direct Fick, dye dilution and thermodulation methods in stable and acutely ill patients.J. Natl. Med. Assoc. 68:281–284, 1976.

    PubMed  CAS  Google Scholar 

  21. 21.

    Hamilton, W.F., R.L. Riley, A.H. Attyah, A. Cournand, D.M. Fowell, A. Himmelstein, R.D. Noble, J.W. Remington, D.W. Richards, N.C. Wheeler and A.C. Witham. Comparison of the Fick and dye injection methods of measuring the cardiac output in man.Am. J. Physiol. 153: 309–321, 1948.

    CAS  PubMed  Google Scholar 

  22. 22.

    Miller, D.E., W.J. Gleason and H.D. McIntosh. A comparison of the cardiac output determination by the Fick method and dye dilution method using indocyomine green dye and a curvette densitometer.J. Clin. Lab. Inves. 59:345–349, 1962.

    CAS  Google Scholar 

  23. 23.

    Werko, L., H. Lagerlof, H. Bucht, B. Wehle and A. Holmgren. “Comparison of Fick and Hamilton methods for determination of cardiac output in man.”Scan. J. Clin. Lab. Inves. 1:109–113, 1949.

    Google Scholar 

  24. 24.

    Powner, D.J., D. Dahl and L. Shucker. Ear densitometer cardiac outputs versus thermodilution outputs (letter).Crit. Care Med. 12:148–149, 1984.

    PubMed  Article  CAS  Google Scholar 

  25. 25.

    Ellis, R., J. Gold, R. Rees and C.W. Lillehei. Computerized monitoring of cardiac output by thermodilution.J. Am. Med. Assoc. 220:507–511, 1972.

    Article  CAS  Google Scholar 

  26. 26.

    Pelletier, C. Cardiac output measurement by thermodilution.Can. J. Surg. 22:347–350, 1979.

    PubMed  CAS  Google Scholar 

  27. 27.

    Ganz, W., R. Donoso, H. Marcos, J. Forrester and H.J.C. Swan. A new technique for measurement of cardiac output by thermodilution in man.Am. J. Card. 27:392–395, 1971.

    PubMed  Article  CAS  Google Scholar 

  28. 28.

    Ganz, W. and H.J.C. Swan. Measurement of blood flow by thermodilution.Am. J. Card. 29:241–245, 1972.

    PubMed  Article  CAS  Google Scholar 

  29. 29.

    Forrester, J.S., W. Ganz, G. Diamond, T. McHugh, D.W. Chonette and H.J.C. Swan. Thermodilution cardiac output determination with a single flow directed catheter.Am. Heart J. 83: 306–311, 1972.

    PubMed  Article  CAS  Google Scholar 

  30. 30.

    Sibille, L., J.M. Vallois, C. Gaudabout and J.J. Pocidalo. Cardiac output measurement with a simplified thermodilution technique comparison with the Fick method.Biomedicine 23:64–67, 1975.

    PubMed  CAS  Google Scholar 

  31. 31.

    Sorensen, M.B., N.E. Bille-Brahe and H.C. Engell. Cardiac output measurement by thermodilution. Reproducibility and comparison with the dye-dilution technique.Ann. Surg. 183:67–72, 1976.

    PubMed  Article  CAS  Google Scholar 

  32. 32.

    Runciman, W.B., A.H. Ilsley and J.G. Roberts. An evaluation of thermodilution cardiac output measurement using the Swan-Ganz catheter.Anes. Intens. Care 9:208–220, 1981.

    CAS  Google Scholar 

  33. 33.

    Olsoon, B., J. Pool, P. Vandermoten, E. Varnauskas and R. Wassen. Validity and reproductivity of determination of cardiac output by thermodilution in man.Cardiology 55:138–148, 1970.

    Google Scholar 

  34. 34.

    Wong, M., A. Skilsky and E. Moon. Loss of indicator in the thermodilution technique.Catheter. Cardiovas. Diag. 4:103–109, 1978.

    Article  CAS  Google Scholar 

  35. 35.

    Runciman, W.B., A.H. Ilsley and J.H. Roberts. Thermodilution cardiac output—A systematic error.Anes. Intens. Care 9:135–139, 1981.

    CAS  Google Scholar 

  36. 36.

    Bilfinger, T.V., C.Y. Lin and C.E. Anagnostopolus. In Vitro determination of accuracy of cardiac output measurements by thermal dilution.J. Surg. Res. 33:409–414, 1982.

    PubMed  Article  CAS  Google Scholar 

  37. 37.

    Corday, E., ed.Controversies in Cardiology. Philadelphia: Davis, 1977, pp. 103–111.

    Google Scholar 

  38. 38.

    White, H.L. Measurement of cardiac output by a continuously recording conductivity method.Am. J. Phys. 151:45–47, 1947.

    CAS  Google Scholar 

  39. 39.

    Smith, M., L.A. Geddes and H.E. Hoff. Cardiac output determined by the saline conductivity method using an intra-artierial conductivity cell.Cardiovas. Res. Center Bull. 5:123–134, 1967.

    CAS  Google Scholar 

  40. 40.

    Geddes, L.A., da Costa and L.E. Baker. Electrical calibration of the saline-conductivity method for cardiac output: A preliminary report.Cardiovas. Res. Center Bull. 10:91–105, 1972.

    Google Scholar 

  41. 41.

    Geddes, L.A., E. Peery and A. Steinberg. Cardiac output using an electrically calibrated flow through conductivity cell.J. Appl. Phys. 37:972–976, 1974.

    CAS  Google Scholar 

  42. 42.

    Grubbs, D.S., D.S. Worley and L.A. Geddes. A new technique for obtaining values of cardiac output in rapid succession.IEEE Trans. Biomed. Engng, BME-29:769–772, 1982.

    Article  CAS  Google Scholar 

  43. 43.

    Trautman, F.G. and R.S. Newbower. A practical analysis of the electrical conductivity of blood.IEEE Trans. Biomed. Engng BME-30:141–149, 1983.

    Article  CAS  Google Scholar 

  44. 44.

    Chinard, F.P., T. Enns and M.F. Nolan. Indicator-dilution studies with “diffusible indicators.”Circ. Res. 10:473–490, 1962.

    PubMed  CAS  Google Scholar 

  45. 45.

    Voorhees, W.D., J.D. Bourland, M.L. Hamp, J.C. Mullikiu and L.A. Geddes. Validation of the saline-dilution method for measuring cardiac output by simultaneous measurement with a perivascular electromagnetic flowprobe.Med. Instrum. 19:34–37, 1985.

    PubMed  Google Scholar 

  46. 46.

    Albertson, M.L., J.R. Barton and D.B. Simons.Fluid Mechanics for Engineers. Englewood Cliffs: Prentice-Hall, 1980, pp. 100–101.

    Google Scholar 

  47. 47.

    Grahn, A.R., H.P. Milton and H.U. Wessel. Design and evaluation of a new linear thermistor velocity probe.J. Appl. Phys. 24:236–246, 1968.

    CAS  Google Scholar 

  48. 48.

    Paulsen, P.K. The Hot-Film anemometer—A method for blood velocity determination.Eur. J. Surg. Res. 12:140–148, 1981.

    Google Scholar 

  49. 49.

    Paulsen, P.K. and J. Anderson. Continuous registration of blood velocity and cardiac output with a Hot-Film anemometer probe, mounted on a Swan-Ganz thermodilution catheter.Eur. J. Surg. Res. 13:376–386, 1981.

    CAS  Google Scholar 

  50. 50.

    Clark, C. Thin film gauges for fluctuating velocity measurements in blood.J. Phys. E. 7:548–556, 1974.

    Article  Google Scholar 

  51. 51.

    Falestti, H.L., K.M. Kiser, G.P. Francis and E.R. Belmore. Sequential velocity development in the ascending and descending aorta of the dog.Circ. Res. 31:328–338, 1972.

    Google Scholar 

  52. 52.

    Reuben, S.R., J.P. Swadling and G.J. Lee. Velocity profiles in the main pulmonary artery of dogs and man, measured with a Thin-Film resistance anemometer.Circ. Res. 27:995–1001, 1970.

    Google Scholar 

  53. 53.

    Kubicek, W.G., J.N. Karnegis, R.P. Patterson, D.A. Witsoe and R.H. Mattson. Development and evlauation of an impedance cardiac output system.Aerospace Med. 37:1208–1212, 1966.

    CAS  PubMed  Google Scholar 

  54. 54.

    Nyboer, J.Electrical Impedance Plethysmography. Charles C. Thomas, 1959.

  55. 55.

    Djordjevich, L., M.S. Sadove, J. Mayoral and A.D. Ivankovich. Relation between chest impedanceZ and (dZ/dT) min.Anesthesiology 55:A114, 1981.

    Article  Google Scholar 

  56. 56.

    Edmunds, A.T., S. Godfrey and M. Tooley. Cardiac output measured by transthoracic impedance cardiography at rest, during exercise and at various lung volumes.Clin. Sci. 63:107–113, 1982.

    PubMed  CAS  Google Scholar 

  57. 57.

    Sramek, B.B. and L.O. Welter. Recent developments in electrical transthoracic impedance resulting in Real-Time monitoring of cardiac output.Anesthesiology 57:A178, 1982.

    Article  Google Scholar 

  58. 58.

    Ebert, T.J., D.L. Eckberg, G.M. Vetrovec and M.J. Cowley. Impedance cardiograms reliably estimate beat-by-beat changes of left ventricular stroke volume in humans.Cardiovas. Res. 18:354–360, 1984.

    CAS  Article  Google Scholar 

  59. 59.

    Saito, Y., G. Toto, H. Terasaki, Y. Hayashida and T. Moriska. The effects of pulmonary circulation pulsatility on the impedance cardiogram.Arch. Inter. Physiol. Biochem. 91:339–344, 1983.

    CAS  Google Scholar 

  60. 60.

    Spinelli, J.C. and M.E. Valentineezzi. Stroke volume in the dog: Measurements by the impedance technique and thermodilution.Med. Prog. Technol. 10:45–53, 1983.

    PubMed  CAS  Google Scholar 

  61. 61.

    Griffith, J.M. and W.L. Henry. An ultrasound system for combined cardiac imaging and Doppler blood flow measurement in man.Circulation 57:925–930, 1978.

    PubMed  CAS  Google Scholar 

  62. 62.

    Magnin, P.A., J.A. Stewart, S. Meyers, Glaf Von Ramm and J.A. Kisslo. Combined Doppler and Phased-Array echocardiographic estimation of cardiac output.Circulation 63:388–391, 1981.

    PubMed  CAS  Google Scholar 

  63. 63.

    Kahlil, H.H. Determination of cardiac output by a new method based on thermodilution.The Lancet, June 22, 1963, pp. 1352–1354.

    Google Scholar 

  64. 64.

    Khalil, H.H., T.Q. Richardson and A.C. Guyton. Measurement of cardiac output by thermal-dilution and direct Fick methods in dogs.J. Appl. Phys. 21:1131–1135, 1966.

    CAS  Google Scholar 

  65. 65.

    Barankay, T., T. Jansco, S. Nagy and G. Petri. Cardiac output estimation by a thermodilution method involving intravascular heating and thermistor recording.Acta Physiol. Acad. Sci. Hungaricae 38:167–173, 1970.

    CAS  Google Scholar 

  66. 66.

    Martin, P.J., J.H. Philip, M.C. Long and R.S. Newbower. The implications of thermal noise for continuous cardiac output monitoring.Proc. 15th AAMI Ann. Meeting, 1980, p. 126.

  67. 67.

    Newbower, R.S., M.C. Long, L.M. Rubin and M.J. Tolkoff. Continuous electronic thermodilution methods.Proc. 29th ACEMB Meeting, 1976, p. 37.

  68. 68.

    Philip, J.H., M.J. Tolkoff, M.C. Long and R.S. Newbower. Continuous measurement of cardiac volume and output.Proc. 31st ACEMB Meeting, 1978, p. 116.

  69. 69.

    Philip, James H., Michael C. Long, Michael D. Quinn and Ronald S. Newbower. Continuous thermal measurement of cardiac output.IEEE Trans. Biomed. Engng BME-31:393–400, 1984.

    Article  CAS  Google Scholar 

  70. 70.

    Shanarian, A., M.B. Vivaudou, M.L. Polanyi, R.S. Peura and G.W. Welch. Single thermistor system for continuous cardiac output.IEEE Front. Engng Comp. Health Care 10.3.1–10.3.4, 1983.

    Google Scholar 

  71. 71.

    Barash, P.G., H. Afshar, and H. Kay. Ejection fraction by thermal dilution technique: A reality?Anesthesiology 34:A26, 1982.

    Article  Google Scholar 

  72. 72.

    Kay, H.R., M. Afshar, R. Barash, W. Webler, A. Iskandrian, C. Bemis, A. Hakki and E. Mundth. Measurement of ejection fraction by thermal dilution techniques.J. Surg. Res. 34: 337–345, 1983.

    PubMed  Article  CAS  Google Scholar 

  73. 73.

    Wikswo, John P., Jr., Noninvasive magnetic detection of cardiac mechanical activity: Theory.Med. Phys. 7:297–306, 1980.

    PubMed  Article  Google Scholar 

  74. 74.

    Katila, T., R. Maniwski, T. Tuomisto, T. Varpula and P. Siltanen. Magnetic measurement of cardiac volume changes.IEEE Trans. Biomed. Engng BME-29:16–25, 1982.

    Article  CAS  Google Scholar 

Download references

Author information



Corresponding author

Correspondence to Kenneth C. Mylrea.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Ehlers, K.C., Mylrea, K.C., Waterson, C.K. et al. Cardiac output measurements. A review of current techniques and research. Ann Biomed Eng 14, 219–239 (1986).

Download citation


  • Cardiac output
  • Ejection fraction
  • Indicator dilution