Characterization of Cerebral Hemodynamics in Newborns with A History of Chronic Hypoxia

Аннотация

Aim and Context: The aim of this study is to investigate the impact of chronic intrauterine hypoxia on cerebrovascular pathology in newborns. This is an important topic because hypoxia (a lack of oxygen) in the womb can have a significant effect on the development of the brain and the central nervous system of the child. Study of Endothelial Dysfunction Markers: The author conducted research on the levels of endothelin-1 in the blood of newborns. Endothelin-1 is a biologically active substance produced by vascular endothelial cells. Elevated levels of this marker may indicate vascular endothelial damage or dysfunction. Study of Hemostasis Parameters: Hemostasis is the process of controlling bleeding, and in the article, the author also investigated several hemostatic parameters, including the level of fibrinogen, which is an important factor in the blood clotting process. Results: The levels of fibrinogen and endothelin-1 were found to be elevated in newborns who experienced chronic intrauterine hypoxia. This may indicate disturbances in the blood clotting system and vascular endothelial function. Elevated levels of endothelin-1 can also affect cerebral hemodynamics, i.e., the blood European International Journal of Multidisciplinary Research 138 https://eipublication.com/index.php/eijmrms and Management Studies European International Journal of Multidisciplinary Research and Management Studies supply to the brain. For healthy newborns in the first day (especially the first hours) of life, a thrombogenic tendency in hemostasis is Conclusion: The study highlights the importance of characteristic, which changes to a tendency for researching cerebrovascular pathology and hypocoagulation and hypoaggregation on the 3rd to 4th endothelial dysfunction markers in newborns, day of life. In children with asphyxia, this tendency is especially those who experienced hypoxia before or more pronounced. However, in cases of severe during childbirth. This helps understand the asphyxia, there is a significant increase in the blood's biochemical changes associated with this pathology coagulation potential [9]. and what precautionary measures or treatments can be applied. Elevated endothelin-1 (ET-1) has been observed in umbilical cord blood in newborns with hypoxic brain damage [2,7]. The primary mechanism of action of ET Keywords: Hypoxia, hemostasis, endothelin-1, involves the activation of calcium release, leading to: fibrinogen, cerebral blood flow velocity, resistance 1. Stimulation of platelet adhesion and aggregation and index. secondary hemostasis. 2. Contraction and growth of vascular smooth muscle, Introduction: Frequency of perinatal hypoxia is not leading to vessel wall thickening and vasoconstriction decreasing. 60-80% of all central nervous system (CNS) [2,10]. diseases in children are associated with perinatal A significant increase in the levels of ET-1 in the blood, hypoxia [1,2]. along with a significant decrease in endothelial nitric In the development of chronic intrauterine fetal oxide production, indicates a predominance of hypoxia, transitioning to neonatal hypoxia, three main vasoconstriction over vasodilation in patients who have groups of causes are identified: experienced acute cerebral blood flow disturbances. 1. Maternal extragenital diseases - thyroid diseases, This results in vasospasm and slowed blood flow [2]. The bronchial asthma, anemia, heart rhythm disorders, degree of brain tissue damage directly correlates with smoking, neurocirculatory dystonia, obesity, diabetes. the severity of endothelial dysfunction [7,10]. 2. Disorders of uteroplacental circulation (maternal ET-1 influences cerebral autoregulation processes by hypertension or arterial hypotension). narrowing cerebral blood vessels and reducing cerebral 3. Disturbances of fetal-placental circulation (tight blood flow below the ischemic threshold, which can coiling of the umbilical cord around the neck, body, trigger cerebral infarction [10]. It has been found that true knots of the umbilical cord, and placental ET-1 initiates cerebral artery spasm as a result of its abruption) [2]. direct action on the vascular wall and through the depolarization of neurons, which is caused by the One of the main causes of hemorrhagic and ischemic activation of endothelin receptors type A and brain damage in newborns is disorders of cerebral phospholipase C [2,10]. hemodynamics [5]. Hypoxia is recognized as a leading etiological factor in particular cerebrovascular Objectives disorders, leading to the development of hemorrhagic The aim of this study was to investigate the state of and ischemic damage to the central nervous system certain hemostasis parameters, vascular endothelium, (CNS) in newborns [4]. and cerebral hemodynamics in newborns who One of the most important factors leading to structural experienced chronic intrauterine hypoxia. brain damage is a disturbance in cerebral blood flow METHODS against the background of hypoxia. Hemodynamic U