Journal of Clinical Monitoring

, Volume 12, Issue 3, pp 225–230

Reflectance pulse oximetry in fetal lambs: Subcutaneous vessels and vasoconstriction affect its reliability

  • Roel Nijland
  • Henk W. Jongsma
  • Ineke M. Verbruggen
  • Jan G. Nijhuis
Original Articles


Objective. Reflectance pulse oximetry (RPOX) has been introduced for intrapartum fetal surveillance. The purpose of this study was to describe two possible effects on the reliability of RPOX, namely the effect of the presence of a subcutaneous vein and the effect of vasoconstriction by adrenaline, both at fetal SaO2 levels.Methods. In four anesthetized fetal lambs, a prototype 660/890 nm reflectance sensor (Nellcor Inc.) was placed on the fetal head, with the photodiode of the sensor precisely over a superficial subcutaneous vein. Measurements were made before and after coagulation of the vein. In five anesthetized fetal lambs, one or two reflectance sensors were placed on the fetal head and/or neck and adrenaline was administered in doses of 0.02 to 0.04 mg via a brachial artery. Pulse oximeter saturation readings (SPO2) were compared with continuous arterial oxygen saturation (SaO2) values obtained using a fiberoptic catheter (Opticath, Abbott) in the carotid artery.Results. When the sensor was placed over the vein, the pulse oximeter read 18% to 24% too low at a SaO2 level of 20% to 50%. After coagulation of the vein, SpO2 readings were in agreement with fiberoptic SaO2 values. Administration of adrenaline resulted in a large overestimation of the SaO2 in 6 of the 7 measurements.Conclusions. Subcutaneous veins and vasoconstriction can affect the reliability of reflectance pulse oximetry. As comparable situations may occur during labor, SpO2 readings should be interpreted with caution when this kind or comparable types of RPOX sensors are used at low SaO2 levels.

Key words

Measurement techniques reflectance pulse oximetry: accuracy Monitoring: hemoglobin oxygen saturation Fetal lambs 


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  1. 1.
    Tremper KK, Barker SJ. Pulse oximetry. Anesthesiology 1989; 70: 98–108PubMedGoogle Scholar
  2. 2.
    Wukitsch MW, Petterson MT, Tobler DR, Pologe JA. Pulse oximetry: Analysis of theory, technology, and practice. J Clin Monit 1988; 4: 290–301PubMedCrossRefGoogle Scholar
  3. 3.
    Kelleher JF. Pulse oximetry. J Clin Monit 1989; 5: 37–62PubMedCrossRefGoogle Scholar
  4. 4.
    Severinghaus JW, Kelleher JF. Recent developments in pulse oximetry. Anaesthesiology 1992; 76: 1018–1038CrossRefGoogle Scholar
  5. 5.
    Harris AP, Sendak MJ, Chung DC, Richardson CA. Validation of arterial oxygen saturation measurements in utero using pulse oximetry. Am J Perinat 1993; 10: 250–254Google Scholar
  6. 6.
    Dassel AC, Graaff R, Aarnoudse JG, Elstrodt JM, Heida P, Koelink MH, de Mul FF, Greve J. Reflectance pulse oximetry in fetal lambs. Pediatric Research 1992; 31: 266–269PubMedCrossRefGoogle Scholar
  7. 7.
    Schmitt JM. Simple photon diffusion analysis of the effects of multiple scattering on pulse oximetry. IEEE Trans Biomed Eng 1991; 38: 1194–1203PubMedCrossRefGoogle Scholar
  8. 8.
    Graaff R. Tissue optics applied to reflectance pulse oximetry. Thesis 1993, Groningen, The NetherlandsGoogle Scholar
  9. 9.
    Johnson N, Johnson VA, Fisher J, Jobbins B, Bannister J, Lilford RJ. Fetal monitoring with pulse oximetry. Br J Obstet Gynaecol 1991; 98: 36–41PubMedGoogle Scholar
  10. 10.
    Dildy CA, van den Berg PP, Katz M, Clark SL, Jongsma HW, Nijhuis JG, Loucks CA. Intrapartum fetal pulse oximetry: Fetal oxygen saturation trends during labor and relation to delivery outcome. Am J Obstet Gynecol 1994; 171: 679–684PubMedGoogle Scholar
  11. 11.
    Gardosi JO, Schram CM, Seymonds EM. Adaptation of pulse oximetry for fetal monitoring during labour. Lancet 1991; 337: 1265–1267PubMedCrossRefGoogle Scholar
  12. 12.
    Nijland R, Ringnalda B, Jongsma HW, Oeseburg B, Zijlstra WG. Measurement of oxygen saturation by multiwavelength analyzer influenced of interspecies differences. Clin Chem 1994; 40: 1971PubMedGoogle Scholar
  13. 13.
    Nijland R, Jongsma HW, Menssen JJM, Nijhuis JG, van den Berg PP, Oeseburg B. Reflectance pulse oximetry: accuracy of measurements from the neck of fetal lambs. Thesis 1995, Nijmegen, The NetherlandsGoogle Scholar
  14. 14.
    Nijland R, Jongsma HW, Nijhuis JG, Oeseburg B. The accuracy of a fiberoptic oximeter over a wide range of arterial oxygen saturation values in piglets. Acta Anaesthesiologica Scandinavica 1995; 39: suppl. 107, 71–76CrossRefGoogle Scholar
  15. 15.
    Nijland R, Jongsma HW, van den Berg PP, Nijhuis JG, Oeseburg B. The effect of pulsating arteries on reflectance pulse oximetry: Measurements in adults and neonates. J Clin Monit 1995; 11: 118–122PubMedCrossRefGoogle Scholar
  16. 16.
    Kim JM, Arakawa K, Benson KT, Fox DK. Pulse oximetry and circulatory kinetics associated with pulse volume amplitude measured by photoelectric plethysmography. Anesth Analg 1986; 65: 1333–1339PubMedGoogle Scholar
  17. 17.
    Gardosi JO, Damianou D, Schram CMH. Artifacts in fetal pulse oximetry: Incomplete sensor-to-skin contact. Am J Obstet Gynecol 1994; 170: 1169–1173PubMedGoogle Scholar
  18. 18.
    Schram CMH, Gardosi JO. Artifacts in fetal pulse oximetry: Nonarterial pulsatile signals. Am J Obstet Gynecol 1994; 170: 1174–1177PubMedGoogle Scholar
  19. 19.
    Johnson N, Johnson VA, Bannister J, Lilford RJ. The effect of caput succedaneum on oxygen saturation measurements. Br J Obstet Gynaecol 1990; 9: 493–498Google Scholar
  20. 20.
    Mendelson Y, Yocum BL. Noninvasive measurement of arterial oxyhemoglobin saturation with a heated and a non-heated skin reflectance pulse oximeter sensor. Biomed Instrum Technol 1991; 25: 472–480PubMedGoogle Scholar

Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • Roel Nijland
    • 1
  • Henk W. Jongsma
    • 1
  • Ineke M. Verbruggen
    • 1
  • Jan G. Nijhuis
    • 1
  1. 1.Department of Obstetrics and GynaecologyUniversity Hospital Nijmegen 415 GYNHB NijmegenThe Netherlands

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