Diagnosis of fetal asphyxia depending on the change of blood flow of fetal middle cerebral artery and umbilical artery using color Doppler ultrasonography

Abstract

Introduction: Ultrasonography has been used in the medical field for more than 50 years and estimated to be safe. The aim of the study was to set the criteria for the diagnosis of fetal asphyxia depending on the indices of fetal middle cerebral artery (FMCA) and umbilical artery (UA). Subjects and Methods: Color Doppler ultrasound (ALOKA-SSD1700) was used to confirm the dynamics of blood flow indices in fetal arteries. Among 417 pregnant women (327 normal and 90 with fetal distress), various arterial velocimetric parameters (ratio of systole to diastole and pulsatility and resistance indexes) were evaluated in the FMCA and UA. t-test and Chi-square test were used for the comparison of average and ratios, respectively, and Ridit test for grading of data. Results: The normal values of blood flow indices of FMCA with gestational age in normal pregnancy reached their peak at the 30th week and then gradually decreased. As for funicular artery, the indices reached their peak at the 28th week and then gradually decreased. The criterion for the diagnosis of fetal asphyxia depending on the blood flow of FMCA and UA is the ratio of resistance indices in the MCA or UA =.10, and the sensitivity, specificity, and accuracy of diagnosis were 86.7%, 98.8%, and 96.2%, respectively. Conclusion: The study confirmed the normal values and dynamics of the blood flow indices of FMCA and UA according to the number of weeks of normal pregnancy and determined criteria for the diagnosis of fetal asphyxia depending on those indices.