INTRAPARTUM FETAL PULSE OXIMETRY - PRESENT AND FUTURE

Pulse oximetry is widely used to monitor the patient's well-being in a nesthetic and neonatal practice. As a result of recent technologic and theoretical advances, it has emerged as a clinical tool in intrapartu m fetal monitoring. Oximeters record both pulse rate and arterial oxyg en saturation of the fetus and they may be adapted to derive an estima te of peripheral perfusion, Reflectance oximetry is more accurate than transmission oximetry in intrapartum fetal management. This method us es the pulsatile changes of red and infrared light reflected from tiss ue to estimate arterial oxygenation. Pulse oximetry is cheap, non-inva sive, simple to operate, relatively accurate and has a fast response t ime. Factors adversely affecting the accuracy of the pulse oximeter ou tput include transducer displacement, peripheral vasoconstriction, hyp otension, anemia, presence of intravascular dyes, meconium staining, f etal hair and scalp edem. Fetal pulse oximetry is limited by a wide no rmal range and inadequate calibration. The amniochorionic membranes ho wever do not affect oximetry readings so that this method may be appli ed before rupture of the membranes, i.e. before labor. Once successful ly developed, fetal pulse oximetry could potentially be used in combin ation with other monitoring techniques to reduce instrumental and oper ative interventions during labor and improve perinatal outcome.