Measurement of Placental Oxygenation by Transabdominal Near-Infrared Spectroscopy

ABSTRACT

The uteroplacental circulation in the placenta can have a major impact on the fetus. Near infrared spectroscopy (NIRS) is the noninvasive method of measuring changes in blood volumes and oxygen concentrations in living tissue. The purpose of this study is to monitor changes in placental tissue oxygen index (TOI) levels, in patients with intrauterine fetal growth restriction during pregnancy, using NIRS. We measured placental TOI values of 15 normal pregnant woman and 15 patients with intrauterine growth restriction admitted to our hospital. The placenta was assessed by ultrasound examination and NIRS was performed on all patients. The TOI values of the IUGR group when hospitalized was 78.6 ± 1.6 (SD). This value was significantly higher than that of the controls (78.6 ± 1.6 [SD] versus 70.2 ± 0.4 [SD]). And the TOI values of the IUGR group, when measured before delivery, were 77.8 ± 1.6 (SD). The TOI values of the IUGR group before delivery were significantly higher than those of the control group (77.8 ± 1.6 [SD] versus 70.3 ± 0.4 [SD]). We propose that NIRS is a candidate, noninvasive method for assessing placental oxygen dynamics on a real-time basis. In the near future it may contribute to perinatal medical practice.

KEYWORDS

Intrauterine fetal growth retardation - uteroplacental circulation - near infrared spectroscopy

REFERENCES

• 1 Rosen M G, Hobel C J. Prenatal and perinatal factors associated with brain disorders.  Obstet Gynecol. 1986;  68 416-421
• 2 Parer J T. Effects of fetal asphyxia on brain cell structure and function: limits of tolerance.  Comp Biochem Physiol. 1988;  199 711-716
• 3 Mallard E C, Williams C E, Johnston B M, Gluckman P D. Neuronal death in the developing brain following intrauterine asphyxia.  Reprod Fertil Dev. 1995;  7 647-653
• 4 Rivkin M J. Hypoxic-ischemic brain injury in the term newborn. Neuropathology, clinical aspects, and neuroimaging.  Clin Perinatol. 1997;  24 607-625
• 5 Martin Jr C B. Electronic fetal monitoring: a brief summary of its development, problems and prospects.  Eur J Obstet Gynecol Reprod Biol. 1998;  78 133-140
• 6 Parer J T, King T. Fetal heart rate monitoring: is it salvageable?.  Am J Obstet Gynecol. 2000;  182 982-987
• 7 Jobsis F F. Noninvasive infrared monitering of cerebral and myocardinal oxygen sufficiency and circulatory parameters.  Science. 1977;  198 1264-1267
• 8 Peebles D M. Changes in human fetal cerebral hemoglobin concentration and oxygenation during labor measured by near-infrared spectroscopy.  Am J Obstet Gynecol. 1992;  166 1369-1373
• 9 Ramanujam N. Photon migration though fetal head in utero using continuous wave, near infrared spectroscopy: clinical and experimental model studies.  J Biomed Opt. 2000;  5 173-184
• 10 Kakogawa J. Transabdominal measurement of oxygenation of the placenta by near-infrared spectroscopy.  Semi Thromb Hemost. 2005;  31 297-301
• 11 Cope M. System for longterm measurement of cerebral blood and tissue oxygenation on newborn infants by near infrared transillumination.  Med Biol Eng Comput. 1988;  26 289-294
• 12 Brazy J E. Near-infrared spectroscopy.  Clin Perinatol. 1991;  18 519-534