TO THE ISSUE OF THE DEVELOPMENT AN ALGORITHM FOR A DIFFERENTIATED APPROACH TO THE MANAGEMENT OF PERSISTENT PULMONARY HYPERTENSION IN PREMATURE INFANTS

Abstract

The management of premature infants with persistent pulmonary hypertension (PPH) remains a major problem in modernneonatology. In recent years, scientifi c studies have identifi ed the role of oxidative stress (OS) in the development and course of PPH. The reserve for reducing mortality and optimizing the management of premature infants with respiratory distress syndrome (RDS) and asphyxia is the development of an algorithm for a diff erentiated approach to the management of PPH in premature infants, taking into account the severity and dynamics of OS, and its implementation into clinical practice. Aim of the study. To increase the eff ectiveness of management of premature infants with persistent pulmonary hypertension with asphyxia and respiratory distress syndrome based on the development of an algorithm for a diff erentiated approach to the management of pulmonary hypertension taking into account the levels of oxidative stress as determined by urinary 8-hydroxy-2-deoxyguanosine (8-OHdG).Material and methods. 100 premature infants between 26/1-34/6 weeks of gestation were included in the study: groupI consisted of 50 infants with RDS, group II – 50 newborns with RDS associated with perinatal asphyxia. The presence and severity of PPH was determined in all infants on the fi rst and third to fi fth day of life by echocardiography (EchoCG), and quantitative determination of 8-OHdG level (ng/ml) – in 44 infants on the fi rst day, and in dynamics – on the third to fi fth day of life by enzyme- linked immunosorbent assay (ELISA). For radiographic evaluation of PPH, all infants underwent chest radiography with determination of Moore’s, Schwedel’s and cardiothoracic index (CTI). The research was conducted in compliance with bioethical requirements as part of the planned scientifi c work of the Department (state registration number 0122U000025).Results. It was found that the characteristics of pulmonary hypertension in premature infants with RDS were signifi cantly lower levels of mean pressure in the pulmonary artery (mPAP) on the fi rst and 3-5 days of life than in children with perinatal asphyxia. It was noted that the factors with high diagnostic signifi cance determining the occurrence of persistent pulmonary hypertension are: birth weight <1500 g; presence of perinatal asphyxia; low Apgar score on the 1st (1-3 points) and on the 5th minute of life (<7 points); gestational age <30 weeks; non-appropriateness for gestational age; male sex. Furthermore, it was found that urinary 8-OHdG levels as a biomarker of OS in preterm infants with RDS and perinatal asphyxia correlated with mPAP on the fi rst and third to fi fth days of life, and that urinary 8-OHdG levels had a high diagnostic value for determining the risk of developing severe PPH on the third to fi fth days of life. The diagnostic signifi cance of the data of the comprehensive radiological assessment of PPH – the radiological indices of Moore, Schwedel, CTI for the development of severe PPH was analyzed and the correlations between the indices and mPAP and between the indices and the level of 8-OHdG were established. The Schwedel index showed the highest reliability in all cases.Conclusion. On the basis of scientifi cally established relationships between clinical, laboratory, radiological and genderaspects of premature infants with perinatal pathology and the identifi ed diagnostic and prognostic values of urinary 8-OHdG, an algorithm for a diff erentiated approach to the management of PPH was developed. Determination of the degree of OS and mPAP in premature infants allows us to adjust and individualize the tactics of respiratory support in the management of premature infants, thus improving the quality of medical care of premature infants with RDS and perinatal asphyxia. In prematurely born children in perinatal centers, additional determination of the severity of RDS based on the level of 8-OHdG in urine allows to predict the adverse course of PPH and the development of complications: bronchopulmonary dysplasia, intraventricular hemorrhage III-IV grade, retinopathy II-III grade, hearing impairment, hypoxic- ischemic lesions of the central nervous system II-III grade in prematurely born children.