Elchalal U, Weissman A, Abramov Y, Abramov D, Weinstein D
Department of Obstetrics and Gynecology, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
Int J Gynaecol Obstet. 1995 Aug;50(2):131-7. doi: 10.1016/0020-7292(95)02440-n.
Pulse oximetry is widely used to monitor the patient's well-being in anesthetic and neonatal practice. As a result of recent technologic and theoretical advances, it has emerged as a clinical tool in intrapartum fetal monitoring. Oximeters record both pulse rate and arterial oxygen saturation of the fetus and they may be adapted to derive an estimate of peripheral perfusion. Reflectance oximetry is more accurate than transmission oximetry in intrapartum fetal management. This method uses the pulsatile changes of red and infrared light reflected from tissue to estimate arterial oxygenation. Pulse oximetry is cheap, non-invasive, simple to operate, relatively accurate and has a fast response time. Factors adversely affecting the accuracy of the pulse oximeter output include transducer displacement, peripheral vasoconstriction, hypotension, anemia, presence of intravascular dyes, meconium staining, fetal hair and scalp edema. Fetal pulse oximetry is limited by a wide normal range and inadequate calibration. The amniochorionic membranes however do not affect oximetry readings so that this method may be applied before rupture of the membranes, i.e. before labor. Once successfully developed, fetal pulse oximetry could potentially be used in combination with other monitoring techniques to reduce instrumental and operative interventions during labor and improve perinatal outcome.
脉搏血氧饱和度测定法在麻醉和新生儿护理中被广泛用于监测患者的健康状况。由于最近的技术和理论进展，它已成为产时胎儿监测的一种临床工具。血氧计可记录胎儿的脉搏率和动脉血氧饱和度，还可用于估算外周灌注情况。在产时胎儿管理中，反射式血氧测定法比透射式血氧测定法更准确。该方法利用从组织反射的红光和红外光的脉动变化来估算动脉氧合情况。脉搏血氧饱和度测定法价格便宜、无创、操作简单、相对准确且响应时间快。对脉搏血氧计输出准确性产生不利影响的因素包括传感器移位、外周血管收缩、低血压、贫血、血管内染料的存在、胎粪污染、胎儿毛发和头皮水肿。胎儿脉搏血氧饱和度测定法受正常范围宽和校准不足的限制。然而，羊膜绒毛膜并不影响血氧测定读数，因此该方法可在胎膜破裂前，即分娩前应用。一旦成功开发，胎儿脉搏血氧饱和度测定法有可能与其他监测技术结合使用，以减少分娩期间的器械和手术干预，并改善围产期结局。
