Evaluation of near infrared spectroscopy technique in diagnosing intrapartum hypoxic-ischemic cerebral injury

Abstract

Objective To discuss the significance of near infrared spectroscopy (NIRS) in evaluation of intrapartum hypoxic-ischemic cerebral injury, and to provide a method to evaluate neonatal brain damage objectively and quantitatively. Methods A total of 63 neonates with fetal distress were divided into hypoxic-ischemic encephalopathy(HIE) group and non-HIE group. Thirtyfive newborns with no fetal distress were chosen as controls. Using NIRS, the brain regional oxygen saturation(rSO2) in these neonates were measured. Evaluation of brain rSO2 in the diagnosis of HIE was analyzed with receiver operating characteristic (ROC) curve. Results At the time of fetal head visible on vulval gapping and 5 min after birth, the HIE group showed decreased brain rSO2[(36. 6±5.0)% and (52. 0±4. 2)%], comparing with control group[(45. 9±4. 6)% and (59. 6±4. 4)%]and non-HIE group[(44.1±3.1) % and (57. 6±3. 5) %](P<0. 01) . The brain rSO2 was positively correlated with the pH and oxygen saturation of umbilical artery blood in all groups (P<0. 01). When the cut-off value of brain rSO2 was <39. 5% at fetal head visible on vulval gapping, the sensitivity and specificity of assessing HIE were 67% and 93%, respectively, while 70% and 86% when the cut-off value was <53. 5% at 5 min after birth. Conclusions The brain rSO2 obtained by NIRS could be used to evaluate brain oxygenation, and may be useful in predicting HIE in neonates with fetal distress. Key words: Spectroscopy, near infrared; Blood gas analysis; Fetal Distress; Hypoxiaischemia, brain; Fetal monitoring