Correlation between NIR spectroscopy and pulse oximetry in the fetus.

At the Women's University Hospital Würzburg, pulse oximetry as well as Near Infrared Spectroscopy (NIR) measurements are performed on the fetus during labor in order to compare both methods. Changes of oxygen saturation seem to be positively correlated to concentration changes of oxidized hemoglobin measured by NIR, partially correlated to those of total hemoglobin, and partially correlated negatively to those of reduced hemoglobin. No correlation was found between oxygen saturation changes and those of cytochrome aa3, perhaps due to a longer lagtime. Pulse oximetry as well as NIR Spectroscopy may prove helpful tools for fetal surveillance. Both must be studied particularly with reference to FBA and fetal outcome before clinical decisions can be influenced by these methods.