An in vivo method utilizing derivative near-infrared spectroscopy was developed to noninvasively determine cerebral venous hemoglobin O2 saturation (SV(O2)). The method was tested on eight pentobarbital-anesthetized dogs ventilated with differing inspired O2 mixtures to force changes in SV(O2) over a wide range. Spectral data obtained by transilluminating the tissues surrounding the superior sagittal sinus (SS) were transformed into first derivative units for correlation with SV(O2) data measured from the SS. Linear regression analysis was applied to data obtained from five dogs and used to build a three-wavelength algorithm for predicting brain SV(O2). In three dogs, SV(O2) was varied to test this equation ability to predict SV(O2). The standard deviation of differences between measured SV(O2) and Sv(O2) predicted from 31 separate spectra was 3.2%. These predicted values, when regressed against the sampled SV(O2), yielded an r value of 0.97. The results demonstrate that during hypoxic hypoxia (HH) it is possible to noninvasively quantify SV(O2) with the use of infrared spectroscopy.
|Original language||English (US)|
|Journal||American Journal of Physiology - Heart and Circulatory Physiology|
|State||Published - 1989|
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine
- Physiology (medical)