Особенности кровотока в средней мозговой артерии плода в функциональном тесте с акустической стимуляцией

Abstract

The objective: to study the characteristics of fetal cerebral blood flow in the conditions of the test with acoustic stimulation (TAS) for some types of pregnancy pathology that determine an increased perinatal risk. Materials and methods. A total of 174 women with a single pregnancy without congenital malformations of the fetus were examined in 34–40 weeks, which were divided into four clinical groups: with an uncomplicated full-term pregnancy, childbirth through the natural birth canal in a period of 38–41 weeks; and three groups with increased perinatal risk due to hypertensive complications; history of cesarean section; pelvic presentation of the fetus. For TAS, a technique developed by M. Sovilj, A. Ljubic, known as “prenatal hearing screening” was used. Vascular resistance indices were estimated in the middle cerebral artery of the fetus before and after the delivery of a sound stimulus (intensity 90 dB, frequency 1500–4500 Hz, duration 0.2 s) at a right angle at a distance of 5 cm from the pregnant woman’s abdomen in the projection of the fetal auricular. According to the measurement results, the coefficient of vascular reactivity was calculated. Results. The average indices of the initial (background) resistance of fetal cerebral blood flow to the low perinatal risk group and hight perinatal risk did not differ in the groups. Reactive TAS was observed in 73% of the total number of women. A large proportion of reactive TAS was determined in a group of women with pelvic presentation of the fetus (every second observation). A general trend was an increase in vascular resistance in high perinatal risk groups, which was confirmed by significant differences in the vascular reactivity coefficient. An individual analysis of the observations showed that the reaction in the TAS towards the maximum increase in vascular resistance coincides with impaired early neonatal adaptation in children born, which was manifested by transient and persistent cardiorespiratory and neurological disorders. Conclusion. The test with acoustic stimulation of the fetus opens up new possibilities for improving the quality of forecasting and evaluating the condition of the fetus during pregnancy of low and high risk. The feasibility of disseminating the practice of conducting functional tests is dictated by the needs of the effective implementation of the perinatal risk strategy. Key words: acoustic stimulation, perinatal pathology, prognosis.