Hypoxic-ischemic Central Nervous System Research Articles

Promising biomarkers of blood-brain barrier permeability impairment in rehabilitation of infants with perinatal hypoxic-ischemic central nervous system injury

Promising biomarkers of blood-brain barrier permeability impairment in rehabilitation of infants with perinatal hypoxic-ischemic central nervous system injury

Blood-brain barrier breach after acute cerebral hypoxia in infants

Background. Neuronal lesion, including hypoxic-ischemic damage to the central nervous system (CNS) in perinatal period, leads to the release of neuron-specific enolase (NSE) into peripheral bloodstream. Consequently, NSE can be considered as a biological marker of nervous system injury. Based on NSE level analysis, timely rehabilitation for newborns can be provided, thereby reducing the likelihood of complications associated with CNS injury.Objective: retrospective assessment of NSE level in peripheral blood over a 24-week period in infants of different gestational age with perinatal hypoxic-ischemic CNS damage.Material and methods. The study included 49 newborns who had suffered perinatal hypoxic-ischemic CNS lesion. Gestation period differed from 32 to 41 weeks. The control group consisted of 28 healthy full-term infants. NSE levels were measured using enzyme immunoassay. Patients of the main group were additionally divided into subgroups depending on Apgar scores at the 1st minute after birth, gestational age, as well as predominant CNS lesion – hemorrhagic with intraventricular hemorrhages or ischemic with periventricular leukomalacia.Results. Throughout the observation period, NSE concentrations were inversely correlated with Apgar scores: lower Apgar indicators were associated with higher NSE levels. In addition, the subgroup of 32–33-week gestational age had significantly higher NSE concentrations compared with 34–36-week, 37–41-week subgroups, and control group. NSE levels in infants with periventricular leukomalacia were consistently lower than those in newbornes with intraventricular hemorrhage starting from the 1st week. Notably, a delayed increase in serum NSE concentrations was observed at the 4th week.Conclusion. The obtained data indicate that blood-brain barrier permeability for NSE is preserved during perinatal hypoxicischemic CNS injury. Serum NSE concentration measurement can serve as a valuable tool in clinical practice for assessing the effectiveness of therapy at the stages of treatment and rehabilitation.

Epileptic seizures caused by hypoxic-ischemic damage to the central nervous system

Epilepsy is a chronic disease of the brain. There are many risk factors and causes of this disease, but it is known that the peak incidence occurs in the first year of a child's life. This is due to the fact that this pathology in most cases is the outcome of perinatal damage to the central nervous system (CNS), which has a hypoxic-ischemic genesis. Hemodynamic disturbances that occur in hypoxia lead to various metabolic shifts, which is subsequently accompanied by neuronal damage and reduced inhibitory influence over all processes. Based on the analysis of literature data, we studied the mechanisms of development of this disease, peculiarities of its course, and differential diagnostic features of epileptic seizures caused by hypoxic-ischemic CNS lesions.

PROFILE OF NITRIC OXIDE METABOLISM INDICATORS IN PRETERM INFANTS WITH PERINATAL CENTRAL NERVOUS SYSTEM INJURIES

Introduction. Premature infants often experience a heightened risk of brain damage, potentially leading to various disorders affecting motor, cognitive, behavioral, social, and sensory functions. The underlying pathological processes of hypoxic-ischemic central nervous system (CNS) injury predominantly stem from compromised cerebral blood flow and oxygen transport. Timely diagnosis and treatment options for prematurely born children with perinatal CNS damage remain limited. Nitric oxide, a universal regulator of physiological functions, plays a crucial role. Endothelial dysfunction, marked by the loss of the neurovascular protective functions of nitric oxide, could significantly contribute to the development of cognitive impairment in hypoxic-ischemic CNS damage. Objectives. The study aims to evaluate the specificities of nitrate metabolism indicators in premature infants with hypoxic-ischemic CNS lesions in the early neonatal period. This involves examining and comparing clinical indicators characterizing hemodynamics, as well as the levels of nitrites, nitrates, and nitrosothiols in urine among patients in the studied groups. Subjects and Methods. The study comprised 14 premature infants with hypoxic-ischemic CNS injury (main group), with a separate selection of 4 infants who did not survive during the neonatal period. The comparison group included 20 relatively healthy prematurely born children. Stratification was based on the results of a genetic study, specifically the determination of the rs61722009 polymorphism of the eNOS gene. The patients underwent routine clinical examinations, including blood pressure measurements, and assessments of nitrates, nitrites, and nitrosothiols in urine. Subgroups were identified as follows: 1st subgroup - 4bb (n=10), and 2nd subgroup - 4aa/4ab (n=10). Results. It was observed that newborns who did not survive had significantly lower systolic and diastolic blood pressure readings on the first day of life, in comparison to relatively healthy children in the two control subgroups (day 1 - p=0.018; p=0.027; p=0.036; p=0.053). Additionally, they exhibited lower heart rate indicators on the first day (p=0.001; p=0.002). However, overall, hemodynamic indicators in newborns with hypoxic-ischemic central nervous system damage did not show statistically significant differences from the corresponding indicators in relatively healthy children. The results indicate a significantly lower level of diuresis in children who died as a result of severe with hypoxic-ischemic central nervous system damage, probably due to the development of multiple organ failure immediately after birth. As a result, it was found that the levels of nitrites (p<0.001; p<0.0001) and nitrates (p<0.01; p<0.0001) were reduced in children with with hypoxic-ischemic central nervous system damage, compared to children in the control groups, regardless of genotype variant. While the level of nitrosothiols did not differ significantly, it was even much higher in children who did not survive, 3.55±0.39 vs 2.23±0.22; p=0.008. The differences found may indicate a disruption of the regulatory effect of nitric oxyde on vascular tone and the condition of neuroglia, particularly in children with hypoxic-ischemic central nervous system damage, as a result of its insufficient production, as well as insufficient mobilization from the depot due to nitrite and nitrate reductases. Conclusions. Hemodynamic patterns in children from the examined groups, except for those who did not survive, did not exhibit significant differences. The notably lower urine output in deceased children indicates the development of multiple organ failure due to severe hypoxia. In children with hypoxic-ischemic central nervous system damage, there is a reduction in the levels of nitrites and nitrates in urine compared to relatively healthy premature infants, while the level of nitrosothiols did not show significant differences and was even notably higher in children who did not survive. The outcome of studying the levels of nitrates, nitrites, and nitrosothiols in urine in a larger patient sample may lead to the development of an algorithm for early diagnosis and management, contingent on the severity of metabolic disorders resulting from hypoxia, considering the potential influence of nitric oxide on energy deficit and mitochondrial dysfunction.

HISTORY OF PRETERM INFANTS WITH HYPOXIC BRAIN DAMAGE

Relevance. According to the experts of World Health Organization, diseases linked to perinatal hypoxic brain damage account for 70-80% of cases of childhood disability.
 This study aims to explore the historical records of heart rate and respiratory characteristics in preterm infants with hypoxic brain damage.
 Subjects and Methods. A prospective cohort study was conducted involving 160 preterm infants categorized into three groups: group I comprised conditionally healthy children, group II included children with hypoxic-ischemic central nervous system lesions, and group III involved children with hypoxic-hemorrhagic central nervous system lesions.
 Results. The analysis of heart rate parameters according to the data of daily monitoring of electrocardiogram has revealed a positive dynamic of reduction of heterotopic activity and a significant (p<0.05) improvement in the functional state of the conduction system of the heart in all preterm infants aged 20-30 months after a course of timely rehabilitation therapy of hypoxic brain damage. The presence of periodic breathing with respiratory pauses in preterm patients in the neonatal period was established, and a significantly longer duration of apnea was found in children with hypoxic-hemorrhagic central nervous system damage. There has been found an inverse correlation of moderate strength between gestational age and the amount of apnea during the day. Throughout the observation period, there was a gradual establishment of the sleep profile and its structural characteristics, indicating a physiological consolidation process marked by a regular alternation of stable rhythm phases. However, in newborns with hypoxic brain damage, autonomic dysregulation of heart rhythm persisted in the form of hypersympathicotonia. This suggests a high level of electrical instability of the myocardium, underscoring the necessity for ongoing clinical monitoring.

PREVENTION OF REPRODUCTIVE LOSSES ASSOCIATED WITH INTRAPLANTAR ACCUMULATION OF RADIONUCLIDES.

to determine the effectiveness of radioprotective therapy in preventing reproductive losses and perinatal consequences associated with the incorporation of radionuclides in the placenta. According to the research design, the first group consisted of 153 women with reproductive losses in anamnesis and signs of termination of the current pregnancy. The control consisted of 30 women with a physiological pregnancy and an uncomplicated history. Based on the fact that one of the causes of premature termination of pregnancy is the vulnerable effect of 137Cs incorporated in the placenta, «Apple Pectin Antioxidant» (the «APA») with a high sorption potential was included in preventive measures regarding reproductive losses and perinatal consequences. The effectiveness of therapy with the inclusion of «Apple Pectin Antioxidant» was evaluated based on indicators of the fetoplacental complex and pregnancy scenarios. The results were compared with the effectiveness of standard treatment for habitual miscarriage of pregnancy. It was established that the destructive effect of incorporated 137Cs leads to placental dysfunction and fetal distress. Therapy with the inclusion of «APA» more significantly than standard treatment increases the progesterone-synthesizing function of the placenta, microcirculation, adaptation potential, and antioxidant protection of cells with the efficiency of 7.5 %, 10.7 %, 17.7 %, and 43.4 %, respectively. «APA» has a positive effect on the scenarios of pregnancy. «APA» in the composition of therapy to preserve pregnancy contributed to a decrease in the frequency of premature births by 11.4 % and an extension of their term to 34 weeks of gestation. Extending the gestational age of preterm birth reduced the frequency of severe asphyxia by 18.7 %, hypoxic-ischemic central nervous system injury by 13.5 %, respiratory distress by 17.3 %, and intraventricular hemorrhage 2nd and 3rd degrees by 12.7 %.All children were born alive due to the preservation of the compensatory ability of the placenta. Termination of pregnancy is a universal reaction of the mother and the fetus to negative exogenous and endogenous influences. Placental dysfunction is the most frequent cause of reproductive losses. Incorporated 137Cs is one of the factors that disturb the architecture of the placenta. Extreme effects depend on the number of incorporated 137Cs and the compensatory capacity of the placenta. Today, the possibility of internal exposure to 137Cs is associated due to consumption of agricultural products. Unfortunately, the level of food contamination with radionuclides remains higher than permissible. Living in an area with a standard radiation background does not guarantee a person the radiation safety of agricultural products. The confirmation is the accumulation of 137Cs in the placentas of women from different regions of Ukraine. The high efficiency of therapy with «APA» is associated with the removal of radionuclides and the minimization of the effect of internal irradiation, which made it possible to reduce the frequency of termination of pregnancy by 28.0 % due to the reduction of cases of premature births (-11.4 %), spontaneous abortions (-11.0 %), termination of pregnancy (-5.5 %). The «APA» is advisable to prescribe from pregravid and during pregnancy to all women, regardless of the region of residence.

The lead content in biological media term infants with hypoxic-ischemic CNS

Introduction: The frequency of births of infants with perinatal pathology has increased inrecent years. The aim of this study is to determination of lead content in the biomedias ofnewborns with hypoxic-ischemic damage of the central nervous system (CNS).
 Materials andMethods: We studied influence of the lead content in children, which were born with hypoxicischemiclesion CNS (HIL CNS). Determination of this microelement was carried out in theblood serum, erythrocytes and urine of 30 newborn infants which were suffered from asphyxiaafter birth. The comparison group consisted of 30 healthy full-term newborns.
 Results: In thebiomedias of children with the HIL of the central nervous system, a toxic trace element of leadhas been identified which is poorly retained in the placenta, so the fetus is more vulnerable toits toxic effects in the prenatal period. In the article the features of the lead content in serum,erythrocytes and urine in term infants which were born with hypoxic-ischemic CNS lesions areinvestigated. This group of subjects had increased serum and erythrocyte concentration of lead.The high content of lead in the erythrocytes of children with hypoxia which is already at birthmay indicate a transplacental penetration of this toxic trace element and the possibility of itsnegative impact on the course of pregnancy.
 Conclusions: The prognostic significance of thelead content was high. Thus, the informative index (Ī) for lead content in serum is 7.40, and theprognostic factor (PC) is + 15.1. As for the prognostic value of the lead content in erythrocytesand urine, very high predictor properties are established for them: Ī = 7.44; PC = + 7.0 and Ī =13.42; PC = + 16.1 respectively.
 Bangladesh Journal of Medical Science Vol.20(2) 2021 p.330-333

Psychomotor, speech and mental development in children with infantile cerebral paralysis

Purpose of the study . Optimization of the diagnostic algorithm of neuropsychic development in the context of primary pediatric and specialized neurological care on the basis of analysis of the formation of psychomotor, speech and mental abilities in children with infantile cerebral paralysis, formed on the background of hypoxic-ischemic and hypoxic-hemorrhagic perinatal CNS damage. Materials and methods . The article presents an assessment of psychomotor, speech and mental development of 81 children with infantile cerebral paralysis (ICP): 50 patients with hypoxic-ischemic central nervous system damage and 31 patients — with hypoxic-hemorrhagic central nervous system damage. Results . PSlowing of psychomotor development (SPD) was diagnosed in 98.8% of cases. The greatest percentage of children with SPD was noted in children under 1 year of age — 40%. The majority of children with SPD are noted under age 2. The amount of children with the delay in speech development (DSD) was 93.8%. DSD was absent in 5 (6.2%) patients. In children under 1.5 years of age, DSD was noted in 34.2% of all cases, while in the group with hypoxic-ischemic damage (HID) of the central nervous system — 47.9% and only 10.7% — in children with hypoxic-hemorrhagic damage (HHD) of the central nervous system(p < 0.01). At the age of 1.6 up to 2 years, the proportion of children with DSD from the group with HID of the central nervous system was 35.4%, and in the group with HHD of the central nervous system — 82.1% (p < 0.01). Mental retardation (MR) was noted in 28.4% of children. The severe and deep forms of MR were 2 times higher in groups with HHD of the central nervous system (22.2 and 11.1%, respectively). Other mental disorders, caused by brain dysfunction, were diagnosed in 50.6% of patients. The absence of MR and other mental disorders was noted in 21% of cases. Conclusion . Presumably, the cause of high detectability of SPD in children under 2 years of age is late evaluation of the child’s speech abilities by parents . The presence of MR in 1/3 of all children under study, and the presence of other mental disorders in 50.6% of patients, indicates a significant proportion of developmentally delayed children with infantile cerebral paralysis (ICP).

LABORATORY CRITERIA OF PERINATAL DAMAGE OF CENTRAL NERVOUS SYSTEM AT PREMATURE NEWBORNS

Fetal and neonatal hypoxia takes a special place among the damaging factors of central nervous system (CNS). All forms of oxygen deficiency are accompanied by the development of bioenergetic hypoxia, which leads to tension of metabolic processes of the organism. Metabolic effect of hypoxia includes stark reduce of mitochondrial activity due to a significant inhibition enzymes of the Krebs cycle: succinate dehydrogenase (SDH) and lactate dehydrogenase (LDH). In newborn babies is not always possible to objectively assess the condition of the CNS defeat, because very often the severity of lesions does not correspond to clinical symptoms, especially in premature newborns. So far determination the severity of hypoxic-ischemic CNS lesions is still very actual in modern medicine. More objective method of such an assessment is determine the activity of neurospecific enolase (NSE). The aim of the paper is to increase the efficiency of diagnosis of hypoxic CNS lesions in premature infants by determining the activity of NSE and study energy supply during the neonatal period. The concentration of NSE, SDH and LDH were determined in 15 conventionally healthy preterm infants (CHPI), which made the comparison group, and 64 premature babies with hypoxic-ischemic CNS lesions, which were divided into three groups: I group – 26 premature children with mild CNS lesions; II group – 20 premature children with severe hypoxic lesions and low birth weight; III group – 18 premature newborns with severe damage of central nervous system and extremely low birth weight. NSE activity was determined by enzyme immunoassay using reagents of the company «Fujirebio» (Sweden) on an automatic analyzer «Multiscan Plus» company «Labsystems» (Finland). Material for investigation was peripheral venous blood of newborns, which collected by vein punction at morning on an empty stomach. Metabolic effect of hypoxia in premature infants manifested by severe inhibition of mitochondrial respiratory activity, which appears in the reduction of aerobic enzyme activity of SDH and activation serum LDH. During the neonatal period in infants with perinatal hypoxic- ischemic lesions of the CNS levels of the of NSE, SDH and LDG aren’t normalized, that indicated on energy deficiency and requires the development of effective methods of correcting this condition. Perinatal hypoxia in premature neonates causes significant alteration of neuronal membranes and increase concentration in blood such neurospecific protein as NSE, whose concentration correlates with the degree of severity of CNS injury.

Редкие случаи мукополисахаридоза I типа у детей с синдромом Гурлер и Гурлер-Шейе

Two rare cases of mucopolysaccharidosis (MPS) I in children are presented. In the first case, the ophthalmologist suspected a Hurler syndrome in a child aged 1 year with corneal opacities in both eyes, taking into account the unusual appearance of the child, which gradually formed over the year after birth, retarded psychic and speech development and the presence of hypoxic ischemic central nervous system injury (CNS) with hypertensive syndrome, hepatomegalia, and mitral valve prolapse. The diagnosis was confirmed by the results of a biochemical blood test, which showed a decrease in the activity of the enzyme of alpha-L-iduronidase. Genetic testing was recommended for the determination of the proband genotype. The second case was a boy S., aged 3 years and 7 months, with Hurler - Scheie syndrome. Numerous comorbidities (CNS, hypertensive syndrome, hip dysplasia, kyphosis, ambilateral inguinal hernia, etc.) combined with gradual formation of grotesque facial features by the age of eighteen months suggested that genetic testing should be taken during the second year of life. As a result, Q 70X mutation was identified in the heterozygous state and replacement therapy with Aldurazyme was prescribed. Clinical polymorphism and different severity of symptoms combined with rare occurrence was the reason why difficulties were experienced in the early identification of MPS I. Early diagnosis is very important so that the children could be timely referred to experts of the interdisciplinary center with an experience in the specific treatment, which is the most effective in the early stages of the disease. For citation: Babushkin A.E., Khusnutdinova E.G., Ryskulova E.K., Mukhametshina R.M. Rare cases of mucopolysaccharidosis type I in children with Hurler and Hurler - Scheie syndromes. Russian ophthalmological journal. 2018; 11 (1): 53-8. doi: 10.21516/2072-0076-2018-11-1-53-58 (In Russian).

The use of citoflavin in neonatology and pediatrics as a factor improving therapeutic efficacy in patients with central nervous system lesions of various etiology

Possibilities of increasing the therapeutic efficacy in patients with perinatal central nervous system (CNS) lesions of hypoxic-ischemic and infectious etiology are considered. Some questions of pathophysiological features of hypoxic-ischemic CNS disorders in newborns and their connection with further cascade of pathological changes in organs and systems are highlighted. In this light, the authors substantiate the need for adequate and effective neuro- (cerebro-) protection by the timely antioxidant energy correction and antihypoxic therapy with cytoflavin. The use of cytoflavin is justified in terms of efficacy and safety and can be recommended for use in practical health care in neonatology and pediatrics.

NEUROGENETIC ASPECTS OF PERINATAL HYPOXIC-ISCHEMIC AFFECTIONS OF THE CENTRAL NERVOUS SYSTEM

Neurogenetics is a thriving young science greatly contributing to the generally accepted concept of the brain development in health and disease. Thereby; scientists are not only able to highlight new key points in traditional ideas about the origin of diseases; but also to completely rethink their view on the problem of pathology development. In particular; new data on neurogenetics of perinatal affections of the central nervous system (CNS) has appeared. Genetic factors in varying degrees affect perinatal hypoxic-ischemic CNS affections. Prematurity determination stays the most studied among them. Nevertheless; there is increasing evidence of significant epigenetic regulations of neuro-expression caused by hypoxia; malnutrition of a pregnant woman; stress; smoking; alcohol; drugs that either directly pathologically affect the developing brain; or form a brain phenotype sensitive to a perinatal CNS affection. New data obliges to change the approaches to prevention of perinatal CNS affections.

A Rare Cause of Acute Respiratory Distress Syndrome: Near Drowning in Detergent and Sodium Hypo Chlorite Containing Solution

Near-drowning continues to be associated with high mortality and morbidity in both children and adults. With the availability of sophisticated technologies and pediatric intensive care units, victims of near-drowning are now more likely to survive. However this improvement in short-term survival of near-drowning, victims after an acute submersion episode has also resulted in an increase of acute respiratory distress syndrome and persistent hypoxic-ischemic central nervous system injury. Therefore, it is important both to know the acute intensive care unit management of victims of neardrowning and also to understand the progression of the disease. We report a patient who had been near-drowned in :

PROPIONIC ACIDURIA IN A 5-MONTH-OLD CHILD

Propionic aciduria is a rare hereditary metabolic disease with autosomal-recessive inheritance mode associated with organic acid metabolic disorder. Early diagnostics is difficult as clinical symptoms caused by metabolic defects are often observed at hypoxicischemic central nervous system lesion, brain malformations and intrauterine infections. Laboratory examination reveals increased concentration of organic acids in blood and urine. The article presents observation of propionic aciduria in a 5-month-old child.

P209 – 1497 Early diagnosis of hypoxic-ischemic central nervous system injury in newborn babies

P209 – 1497 Early diagnosis of hypoxic-ischemic central nervous system injury in newborn babies

Longitudinal analysis of arterial Doppler parameters in growth retarded fetuses

Doppler parameters enable noninvasive and direct detection of placental insufficiency and brain sparing effect, which occurs as an adaptive mechanism to chronic hypoxemia. It is of great interest if further changes of Doppler parameters, which occur after the detection of the first pathologic value, can anticipate a moment of fetal distress. We investigated growth-restricted fetuses with the brain sparing effect in the time interval between the detection of blood flow redistribution until the distress. The aim of our study was to evaluate longitudinally Doppler parameters in umbilical (Aum), medial cerebral (MCA), renal (AR) and femoral (AF) artery and find: 1) if there are significant changes in their value; 2) the character and time interval of these changes; and 3) if they differ from changes in biophysical profile (BFP). MATERIALS AND METHODS Prospective clinical study evaluated 35 pregnancies with fetal growth restriction. Fetuses were selected for the study if: 1) there were pathologic cerebral/umbilical (C/U) ratio, 2) at least four Doppler examinations in 3-4 days interval were performed and 3) prepartal fetal distress, defined as silent fetal heart rate pattern with spontaneous and late decelerations, was present. In 28 neonates after delivery umbilical artery gas and acid-base status was determined. Blood flow velocity waveforms were evaluated in Aum MCA, AR, and AF. Arterial blood flow was estimated by pulsatility index (Pi), while in Aum we also used: present end-diastolic velocity (PEDV) absent end-diastolic velocity (AEDV) and reverse end-diastolic velocity (REDV). All of the fetuses were monitored by cardiotocogram (CTG) once to twice a day and by BFP twice a week. Elective Cesarean section was done in the presence of distress, except if severe immaturity or extreme malnutrition occurred. RESULTS Etiological factors of placental insufficiency were: 1) hypertensive syndrome (n=26), 2) chronic renal disease (n=3), 3) primary antiphospholipid syndrome (n=2), 4) diabetes mellitus (n=1), 5) cardiac disease (n=1) and 6) unknown (n=2). Initial Doppler examination, with the detection of pathological C/U, was done in time interval between 26. to 32. weeks of gestation (wg) (29.4 ? 2.5) delivery was between 29. to 34. wg (32.2 ? 1.9); and average body weight was 1327 ? 245g. Pathological BFP was registered in 91.4% of fetuses. Cesarian section has not been done, in spite of distress, in two fetuses (5.7%) due to their extreme immaturity and/or malnutrition, so they died "in utero". Hypoxemia was registered in 96.4% (27/28) neonates, while acidosis in 71.4% (20/28). Neonatal morbidity was 93.9% (31/33), neonatal mortality 8.6% while perinatal mortality was 14.3%. We found high significant difference (P&lt;0.001) in Pi Aum, Pi ACM and Pi AR in the time interval between the detection of pathological C/U ratio and fetal distress, while the difference was insignificant for the values of Pi AF (table). The value changes are characterized by: continuing increase of Pi Aum, with a maximum in the last week before the distress; biphasic character of PI MCA - tendency to decrease in the first two and significant increase in the last week; and significant increase of Pi AR one and a half week before the distress (table, graphic). Three weeks before the distress in 7 (53.8%) cases we registered PEDV, in 6 (46.2%) AEDV, while we didn`t register REDV in any case. In the last week there were 3 (8.6%) PEDV, 23 (65.7%) AEDV and 9 (25.7%) REDV.. DISSCUSSION Significant changes in Doppler parameters suggest that even after the blood redistribution in growth restricted hypoxemic fetuses further haemodynamic changes occur. Preterminal increase in Pi Aum can be due to: 1) release of leucotrien, tromboxan and free oxygen radicals and consecutive vasoconstriction in villous arteries; 2) increase of diastolic arterial pressure as a result of hypoxic-ishemic central nervous system (CNS) insult; 3) decreased combined heart minute volume in preterminal phase of hypoxemia. The increase of Pi MCA values is a result of hypoxic-ishemic CNS insult. As a consequence of hypoxia ischemia occurs by two mechanisms: local vasodilatatory agents production decrease, or due to the brain edema. The increase of Pi AR values can be explained by severe hypoxemia with the failure of local autoregulation of renal blood flow. The greatest changes in BFP values were registered in the first half, while in Doppler parameters in the second half of the studied interval suggesting that Doppler parameters more accurately announce fetal distress. We can conclude the following: 1) fetal distress appears after the presence hypoxic-ischemic CNS insult, and therefore late when sequels are concerned; 2) if the fetus is mature, elective delivery should be planed after the appearance of pathological C/U ratio, or with the pathological BFP at the latest, in order to avoid post-hypoxic sequels; 3) if the fetus is immature, pregnancy can be prolonged safely, in spite of pathological C/U ratio and BFP, with intensive monitoring of Doppler parameters until the detection of their increased values.

Glucose affects the severity of hypoxic-ischemic brain injury in newborn pigs.

The administration of glucose has been shown to worsen brain injury in adult animals but has no effect on the severity of injury in newborn rats. We wished to see whether the results in newborn rats could be extended to another newborn animal. In 44 0- to 3-day-old piglets, hypoxic-ischemic central nervous system damage was induced by ligation of both carotid arteries and reduction of their blood pressure to two-thirds normal for one-half hour. In the last 15 minutes of this half hour, oxygen concentration was reduced to 6%. The piglets were randomized to receive either 2 mL/kg 50% dextrose in water followed by 2 mL/kg per hour for 2.5 hours beginning before ischemia or enough insulin to reduce their resting blood sugar to approximately 2 mmol/L. Neurological exam scores in the glucose-treated piglets at 1 day after injury were significantly worse than those in the insulin-treated group. Pathological examination scores were poorer in the glucose-treated group (13.6 +/- 1.9 [mean +/- SEM]) than in the insulin-treated group (24.7 +/- 1.4, P < .01). Increasing serum glucose during hypoxic-ischemic injury to the newborn piglet's brain worsens brain injury.