Non-invasive monitoring of brain oxygen sufficiency on cardiopulmonary bypass patients by near-infra-red laser spectrophotometry

  • M. Tamura
  • T. Tamura
Blood Flow


A new portable high-performance apparatus for near-infra-red (NIR) laser spectrophotometry was developed to monitor the oxygenation state in the human brain. Three different wavelengths of 780,805 and 830 nm of the NIR light illuminated the head using a fibre-optic bundle, and the transmitted or reflected light was detected by a photodiode placed on the forehead. The oxygenated Hb (oxy Hb), deoxygenated Hb (deoxy Hb) content and the Hb (blood) volume changes in the brain were continuously monitored in cardiopulmonary bypass (CPB) patients in the reflectance mode. In hypothermic CPB with selective brain perfusion, the brain bypass flow rates of 0.5 L min−1 at 24–25°C and 0.3 L min−1 at 21–22°C were confirmed as the safe lower limits by our NIR monitoring. During deep hypothermic circulatory arrest, the brain oxy Hb and blood volume decreased significantly. The result indicates that brain Hb oxygenation decreases significantly during circulatory arrest. In the adult patients group, during moderate hypothermic CPB, the brain blood oxygenation level was maintained roughly constant at mean arterial perfusion pressure of over 60 mm Hg, whereas below 50–55 mmHg a progressive decline in the brain Hb oxygenation was observed. These findings led us to conclude that non-invasive monitoring of brain oxygenation using NIR light can provide valuable data at the bed-side regarding tissue metabolism, and it can allow for the proper management of critical patients.


Blood Volume Brain Cardiopulmonary bypass Deoxy Hb Laser spectrophotometry Near-infra-red light Oxy Hb 


  1. American National Standards for the Safe Use of Lasers (1976), American National Standards Institute, Inc., New York, publication Z136.1Google Scholar
  2. Cope, M., andDelpy, D. T. (1988): ‘A system for longterm cerebral blood and tissue oxygenation measurement on newborn infants by near infrared transillumination’,Med. Biol. Eng. Comput.,26, pp. 289–294CrossRefGoogle Scholar
  3. Delpy, D. T., Cope, M., Van der Zee, P., Arridge, S., Wray, S., Wyatt, J. S. (1988): ‘Estimation of optical pathlength through tissue by direct time of flight measurement’,Phys. Med. Biol.,33, pp. 1433–1442CrossRefGoogle Scholar
  4. Ferrari, M., Wilson, D. A., Hanley, D. F., andTraystman, R. J. (1989): ‘Near infrared determined cerebral transit time and oxy- and deoxyhemoglobin relationships during hemorrhagic hypotension in the dog’,Adv. Exp. Med. Biol.,248, pp. 55–62Google Scholar
  5. Govier, A. V., Reves, J. G., McKay, R. D., Karp, R. B., Zorn, G., Morawetz, R. B., Smith, L. R., Adams, M., andFreeman, A. M. (1984): ‘Factors and their influence on regional cerebral blood flow during nonpulsatile cardiopulmonary bypass’,Ann. Thorac. Surg.,38, pp. 592–600CrossRefGoogle Scholar
  6. Henriksen, L., Hjelms, E., andLindegurg, T. (1983): ‘Brain hyperfusion during cardiac operations’,J. Thorac. Cardiovasc. Surg.,86, pp. 202–208Google Scholar
  7. Kuhl, D. E., Alavi, A., Hoffman, E. J., Phelps, M. E., Zimmerman, R. A., Obrist, W. D., Bruce, D. A., Greenberg, J. H., andUzzell, B. (1980): ‘Local cerebral blood volume in head-injured patients’,J. Neurosurg.,52, pp. 309–320CrossRefGoogle Scholar
  8. Murkin, J. M. (1987): ‘Cerebral hyperperfusion during cardiopulmonary bypass: the influence of PaCO2in Hilberman, M. (Ed.): ‘Brain injury and protection during heart surgery (Kluwer, Boston)Google Scholar
  9. Piantadosi, C. A., Hemstreet, T. M., andJobsis-Vandervliet, F. F. (1986): ‘Near-infrared spectrophotometric monitoring of oxygen distribution to intact brain and skeletal muscle tissues’,Crit. Care Med.,14, pp. 698–706Google Scholar
  10. Skov, L., Pryds, O., andGreisen, G. (1991): ‘Estimating cerebral blood flow in newborn infants: comparison of near infrared spectroscopy and 133Xenon clearance’,Paediatr. Res.,30, pp. 570–573Google Scholar
  11. Swan, H. (1984): ‘The importance of acid base management for cardic and cerebral preservation during open heart operations’,Surg. Gynecol. Obstet.,158, pp. 391–414Google Scholar
  12. Takatani, S. (1989): ‘Toward absolute reflectance oximetry: 1. Theoretical consideration for noninvasive tissue reflectance oximetry’,Adv. Exp. Med. Biol.,248, pp. 91–102Google Scholar
  13. Tamura, M., Isshiki, M., Tachibana, H., Kubo, Y., andTamura, T. (1989c): ‘Non-invasive monitoring of tissue oxygen metabolism by NIR laser spectrophotometry; towards clinical application’,Jpn. J. Artif. Organs,5, pp. 1573–1580 (in Japanese with English abstract)Google Scholar
  14. Tamura, M., Isshiki, M., Tachibana, H., andKubo, Y. (1990): ‘Non-invasive assessment of mitochondrial functions in rat brain during and after hemorrhagic shock’,Kokyu to Junkan (Resp. Circ.)38, pp. 165–171 (in Japanese with English abstract)Google Scholar
  15. Tamura, M., Isshiki, M., Tachibana, H., andTamura, T. (1989a): ‘New quantitative method for non-invasive monitoring of tissue blood oxygenation by near infrared spectrophotometry’,Kokyo to Junkan (Resp. Circ.37, pp. 997–1002 (in Japanese with English abstract)Google Scholar
  16. Tamura, M. (1991): ‘Non-invasive monitoring of brain oxygen metabolism during cardiopulmonary bypass by near infrared spectrophotometry’,Jpn. Circ. J.,55, pp. 330–335Google Scholar
  17. Tamura, M., Tachibana, H., Takagi, I., Kubo, Y., andSamezima, N. (1987): ‘Non-invasive tissue oxygen monitoring by near infrared spectroscopy’,Nippon Geka Gakkai Zasshi (J. Jpn. Surg. Soc.),88, pp. 680–685 (in Japanese with English abstract)Google Scholar
  18. Tamura, T., Eda, H., Takada, M., andKubodera, T. (1989a): ‘New instrument for monitoring hemoglobin oxygenation’,Adv. Exp. Med. Biol.,248, pp. 103–107Google Scholar
  19. Wickramasinghe, Y. A. B. D., Livera, L. N., Spencer, S. A., Rolfe, P., andThorniley, M. S. (1992): ‘Plethysmographic validation of near infrared spectroscopic monitoring of cerebral blood volume’,Arch. Dis. Child,67, pp. 407–411CrossRefGoogle Scholar
  20. Wray, S., Cope, M., Delpy, D. T., Wyatt, J. S., andReynolds, E. O. R. (1988): ‘Characterization of the near infrared absorption spectra of cytochrome aa3 and hemoglobin for the non-invasive monitoring of cerebral oxygenation’,Biochem. Biophys. Acta,933, pp. 184–192CrossRefGoogle Scholar
  21. Wyatt, J. S., Cope, M., Delpy, D. T., Van Der Zee, P., Arridge, S., Edwards, A. D., andReynolds, E. O. R. (1990): ‘Measurement of optical path-length for cerebral near-infrared spectroscopy in newborn infants’,Dev. Neurosci.,12, pp. 140–144Google Scholar

Copyright information

© IFMBE 1994

Authors and Affiliations

  • M. Tamura
    • 1
  • T. Tamura
    • 2
  1. 1.First Department of SurgeryAsahikawa Medical CollegeAsahikawaJapan
  2. 2.Analytical Instruments Research LaboratoryShimazu CorporationKyotoJapan

Personalised recommendations