Assessment of nasal and oral flow of amniotic fluid in 46 non-anomalous fetuses with sonographic and echocardiographic examination

Abstract

Objectives: The aim of the paper was to assess nasal and oral amniotic fluid flows, with the use of color ultrasound and spectral Doppler, in normal fetuses. Material and methods:Forty-six fetuses of singleton gestations were studied prospectively. Spectrum imaging and maximal nasal fluid flow velocities were described. Episodes of regurgitation (external flow from the mouth), swallowing (internal flow at the level of oropharynx and then entrance to the esophagus) were evaluated in two groups: Fetuses < 27 weeks of gestation and 27 weeks of gestation and older. Statistical analysis was done using Fischer exact test and t-test at p = 0.05.Results: Twenty-one fetuses were < 27 weeks of gestational age and presented mean maximal both inspiratory and expiratory nasal fluid flow velocities significantly lower than twenty-five fetuses who were ≥ 27 weeks of gestational age (p = 0.035 and p = 0.031 respectively, t-test). Episodes of regurgitation were observed more frequently in group of "younger" fetuses (p = 0.006, Fischer exact test). There was no statistically significant relationship between irregular nasal flow spectrum by color Doppler and gestational age group (p = 0.264, Fischer exact test). Conclusions:Episodes of regurgitation occurred in normal fetuses < 27 th week of gestation. Fast amniotic nasal fluid flows without episodes of regurgitation were observed more frequently in fetuses ≥ 27 weeks and it could be interpreted as an additional sonographic feature of prenatal maturation.

Evaluation of Fetal Breathing-Related Nasal Fluid Flow Doppler in the Third Trimester in Pregnant Women with Fetal Growth Restriction: Preliminary Observations

“…Irregular nasal fluid flows were observed more frequently in the fetuses that were < 27 weeks. In addition, both the mean maximal inspiratory fluid flow and mean maximal expiratory fluid flow were significantly higher in fetuses ≥ 27 weeks than in fetuses < 27 weeks of gestation [6].…”

Ocular Ultrasound

“…53,54 Further, at least one study has been reported that employs color and spectral Doppler in the vicinity of the fetal eye. 55 Shear wave elastography has been reported in the fetus, but not specifically in the fetal eye. 56…”