Hours Of Extrauterine Life Research Articles

Disruption of Cerebellar Granular Layer as a Consequence of Germinal Matrix Intraventricular Hemorrhage in Extreme Prematurity: An Acute Direct Mechanism Too?

Cerebellum is an important brain structure for the future development of motor, cognitive, and behavioral abilities in children. This structure undergoes its most significant growth during the third trimester of pregnancy. Prematurity gathers several risk factors for cerebellar impairment and underdevelopment, and among them is ventricular dilatation following germinal matrix intraventricular hemorrhage (GMH-IVH). In this report, we illustrate how this prevalent complication associated with prematurity may induce secondary cerebellar cortical damage. A premature male born by an emergency Caesarean section displayed massive GMH-IVH at brain ultrasound performed after three hours of extrauterine life and died after 18 hours of life, despite maximized vital support. We report a postmortem histopathological specimen of the cerebellar cortex showing the disruption of the external granular layer (EGL) by hemorrhagic content flowing from the supratentorial ventricles into the fourth ventricle and cisterna magna. The expansion of the ventricular system and the presence of blood in the lateral ventricles can cause inflammation and damage to the cerebellar gyri. Experimental models have shown a thinning of the EGL, suggesting that blood surrounding the cerebellum has a harmful action. Additionally, a sudden influx of cerebrospinal fluid from the lateral ventricles may directly contribute to cerebellar damage, indicating that this may be another way in which the cerebellar gyri are impaired during acute severe GMH-IVH. This is the first histopathologically confirmed case of acute disruption in the cerebellar cortex during a GMH-IVH in a premature baby.

Antenatal diagnosis and management of an encephalocele in Jamaica

Introduction: Encephalocele is a rare fetal anomaly associated with neurodevelopmental morbidity, especially in developing countries where management resources are limited. Case Report: Here, we present a case of antenatal diagnosis of an occipital encephalocele in a 25-year-old multigravida. Ultrasound and magnetic resonance imaging were used throughout the second and third trimesters to guide delivery and plan postnatal repair. A multidisciplinary approach to care, involving maternal–fetal medicine, radiology, neonatology, and neurosurgery specialties, was undertaken from mid-gestation. This multiteam approach afforded predelivery planning that resulted in an uneventful cesarean delivery and surgical correction of the encephalocele within 24 hours of extrauterine life. Conclusion: This case demonstrates that even in the absence of advanced resources for fetal interventions, successful outcomes can be achieved with early diagnosis, a multiteam approach to care and predelivery planning.

Current approaches to assessing the degree of perinatal risk

Aim: to study the factors leading to adverse perinatal outcomes allowing, on this basis, to predict degree of perinatal risk.Materials and Methods. The medical records of 155 patients who performed delivery in 2019–2021 were retrospectively analyzed. The following groups were formed: main group included 56 patients with adverse perinatal outcomes (9 fetuses died antenatally, 36 fetuses born below Apgar score 5, 9 newborns died within the first 168 hours of extrauterine life, 2 infant deaths). The control group included 99 patients with favorable perinatal outcomes. While assessing the data retrieved from medical records, sociobiological and laboratory-instrumental indicators, obstetric-gynecological and somatic anamnesis, the presence of extragenital pathology, the delivery process, information related to child condition at the time of birth and in early neonatal period were analyzed.Results. In patients of the main group, significant differences were revealed compared to control group, respectively: high parity (3 or more deliveries) – 11 (19.6 %) and 15 (15.1 %) (p = 0.001); vomiting of pregnant women in early gestation – 27 (48.2 %) and 14 (14.1 %) (p = 0.005); the presence of uterine scar after two or more caesarean sections – 7 (12.5 %) and 2 (2.1 %) (p = 0.009); former abortions – 24 (42.8 %) and 16 (16.1 %) (p = 0.0017); acute respiratory viral infection in the first trimester – 21 (37.5 %) and 13 (13.1 %) (p = 0.005); threatened abortion in the second trimester – 23 (41.0 %) and 15 (15.1 %) (p = 0.0005); Doppler-based blood flow disorders in the second trimester – 17 (30.3 %) and 11 (11.1 %) (p = 0.008) and in the third trimester – 9 (16.0 %) and 3 (3.0 %) (p = 0.006); altered amniotic fluid index according to ultrasound data in the second trimester – 6 (10.7 %) and 1 (1.0 %) (p = 0.011); intrauterine growth retardation in the third trimester – 15 (26.7 %) and 4 (4.0 %) (p = 0.012); severe preeclampsia – 6 (10.7 %) and 1 (1.0 %) (p = 0.04). In patients of the main group, pregnancy was finished prematurely in 41.1 % of cases compared to 100% term delivery in control group.Conclusion. The risk factors identified, which were manifested in the first and second trimesters of pregnancy may be predictors for adverse perinatal outcomes. Based on the study results for patients of the main and control groups, it was convinced that the topic of predicting favorable and unfavorable perinatal outcome is currently far from being disclosed, which is a long meticulous path of search, analysis and comparison.

Defective liver glycogen autophagy related to hyperinsulinemia in intrauterine growth-restricted newborn wistar rats

Maternal malnutrition plays a critical role in the developmental programming of later metabolic diseases susceptibility in the offspring, such as obesity and type 2 diabetes. Because the liver is the major organ that produces and supplies blood glucose, we aimed at defining the potential role of liver glycogen autophagy in the programming of glucose metabolism disturbances. To this end, newborns were obtained from pregnant Wistar rats fed ad libitum with a standard diet or 65% food-restricted during the last week of gestation. We found that newborns from undernourished mothers showed markedly high basal insulin levels whereas those of glucagon were decreased. This unbalance led to activation of the mTORC1 pathway and inhibition of hepatic autophagy compromising the adequate handling of glycogen in the very early hours of extrauterine life. Restoration of autophagy with rapamycin but not with glucagon, indicated no defect in autophagy machinery per se, but in signals triggered by glucagon. Taken together, these results support the notion that hyperinsulinemia is an important mechanism by which mobilization of liver glycogen by autophagy is defective in food-restricted animals. This early alteration in the hormonal control of liver glycogen autophagy may influence the risk of developing metabolic diseases later in life.

The entropy of RR intervals is associated to gestational age in full-term newborns with adequate weight for gestational age

Introduction The variability of successive RR intervals has been pointed out as an indicator of systemic homeostasis. The entropy of successive RR intervals is associated with a greater adaptive capacity, which is essential after childbirth, characterized by a change from an intrauterine environment that constantly adapts to the fetal demands, to an extrauterine environment that requires constant biological adaptations by the neonate. Objectives To analyze the association between gestational age (GA) and the entropy of RR intervals in term infants with adequate birth weight in the first hours of extrauterine life. Methods In a cross-sectional study design maternal, labor and neonatal characteristics were collected from the obstetric records. Successive RR intervals were recorded from neonates up to 72 hours (i.e. 3 days) of birth. Subjects Fifty term infants, healthy and with adequate birth weight. Outcome measures: the variability of RR intervals was analyzed obtaining the entropy of 1000 successive RR intervals. Pearson’s correlation was used to evaluate the association between GA and the entropy of successive RR intervals, while linear regression was used to obtain the coefficient of determination (r 2) as well as a prediction model. The adequacy of the prediction model was evaluated using the Komolgorov-Smirnov test to evaluate the residuals distribution. Results There was a positive and significant association between the studied variables (r = 0.437; p = .002). The coefficient of determination allowed us to infer that approximately 19.3% of the RR interval entropy from the studied sample can be explained by the GA (r 2 = 0.193; p = .002). The analysis of the residuals distribution confirmed that the regression model obtained here was adequate. Conclusion Our results indicate that, even within a normal range of GA (≥37 a < 42 weeks) and birth weight, a longer intrauterine life allows a greater entropy of successive RR intervals, indicating a greater maturation of biological systems and adaptive capacity.

Cardiac Autonomic Function in the First Hours of Postnatal Life: An Observational Cross-Sectional Study in Term Neonates.

The aim of this study was to evaluate heart rate variability (HRV) within the first hours of extrauterine life in term neonates. HRV at 2-h and 14-h postpartum were compared by means of time domains (iRR, SDNN, and rMSSD); frequency domains (TP, LF, HF, and LF/HF ratio); and Poincare's Plot (SD1 and SD2) indices of HRV in 27 healthy, male, term newborns (NBs) born of elective cesarean delivery. Within 14h after birth, the mean of the iRRs increased (Δ% = 4.4, p < 0.001) as well as parasympathetic indices (rMSSD: Δ% = 32.6; p < 0.03; HF: Δ% = 43.6; p < 0.00; SD1: Δ% = 32.6, p < 0.03). Respiratory rate (RR) decreased (RR: 2h = 48 (43-55) cycle/min vs. 14h = 45 (40-48) cycle/min p < 0.01). We concluded that within the first 14h of birth, cardiac autonomic adjustments are characterized by an increase in parasympathetic activity. Concurrently, there were no significant changes observed in all other HRV indices in healthy, male, term neonates, and born of elective cesarean delivery.

Neurobehavior of mexican newborns in conditions of low perinatal risk

INTRODUCTION: The first hours of life are still a window of opportunity to identify at-risk newborns, but there are few studies focusing on early neonatal behavior.OBJECTIVE: Describe in a cross section the behavior of newborns born in conditions of low perinatal risk under 48 hours of extrauterine life and compare it with historical referents.METHOD: We studied 47 newborns with low perinatal risk, whose behavior was assessed using the Brazelton Neonatal Behavioral Assessment Scale (NBAS). Scores were obtained by item and area, and then were compared with 7 historical referents.RESULTS: Low scores were found, both by item and by areas in up to 25% of the population. NBAS scores were related primarily with age of newborn, weight, and height. Significant differences were found in relation to referents for which higher scores were reported in the majority of cases.CONCLUSIONS: A pattern was found of behavior, in which the same areas or items caused greater or lesser difficulty in achieving higher scores or those which required a certain level of adaptation to the environment, which would lead us to believe that our newborns should attain the scores seen in other populations as they advance in age.

Cutaneous lesions and disorders in healthy neonates and their relationships with maternal-neonatal factors: a cross-sectional study.

Cutaneous lesions are very common in neonates. Although a number of studies have reported on their incidence, very little is known about the factors that influence them. We set out to investigate a large population of neonates with the aims of achieving an overall picture of neonatal skin manifestations, and examining their relationships with various maternal, neonatal and perinatal factors. This study was conducted on neonates born at the Department of Obstetrics and Gynaecology at the University of Szeged between June 2013 and July 2015. A total of 4658 consecutive infants underwent a whole-body skin examination within the first 72 hours of extrauterine life. The official neonatal medical charts were used to collect data on the history of the participating neonates and on maternal factors. 74.35% of the neonates exhibited at least one skin manifestation. The major diagnosis groups were transient, benign cutaneous lesions; vascular lesions; traumatic, iatrogenic, congenital or acquired disorders with skin injuries; pigmented lesions; and developmental abnormalities or benign skin tumours. The relationships between the skin findings and six neonatal or maternal factors were examined: gender, gestational age and birth weight of the neonates; maternal age and the number of previous pregnancies of the mothers, and mode and circumstances of the delivery. We found several significant correlations between the examined maternal/neonatal factors and the occurrence of birthmarks and neonatal skin disorders. Of course, further studies are required to confirm and better understand these associations.

Assessment of the vitality of the newborn: An overview

Four million newborns die in the world every year, and reports indicate that 98% of those deaths occur in developing countries. The infant mortality rate in children under 5 years of age in Mexico has decreased progressively, in contrast to the neonatal mortality rate, where the reduction was not significant. For this reason, it is necessary and important to have resources that make it possible to assess, rapidly and efficiently, the physiological status of newborns. The objective of this review is to identify the factors involved in the vigor of the newborn. This review will thus allow us to understand the relation that exists between the vitality scores and birth weight, the repercussions of the process of prenatal asphyxia, age of gestation and mortality. Once the factors involved in decreases in the vigor of the newborn have been reviewed, additional studies will be required to use animal models to test different pharmacological therapies that newborn humans have shown their value for early diagnosis and treatment, as a means of improving their physiological and hemodynamic condition during the first hours of extra uterine life, as this is a fundamental factor in their survival.

Metabolic coupling and the role played by astrocytes in energy distribution and homeostasis.

The lactate accumulated during late gestation is actively oxidized within the first hours of extrauterine life (Medina et al., 1980; Persson and Tunell, 1971), indicating that neonatal tissues actively utilize blood lactate. It is noteworthy that gluconeogenesis is not yet induced in these circumstances (Fernandez et al., 1983; Medina et al., 1980), in agreement with the idea that lactate is utilized directly as a source of energy and carbon skeletons by some neonatal tissues (see: Medina et al., 1992). Since lactate removal takes place at a very high rate, it is likely that several tissues would be involved in lactate utilization. Thus, it has been reported that neonatal lung (Patterson et al., 1986), heart (Fernandez, E. and Medina, J. M., unpublished results), and liver (Almeida et al., 1992) utilize lactate for energy production and/or lipogenic purposes. However, special attention has been paid to lactate utilization by the brain, probably because this organ must continue its development even under the starvation that occurs during the presuckling period. Lactate utilization by the brain has been reported in fetal (Bolanos and Medina, 1993), early newborn (Arizmendi and Medina, 1983; Fernandez and Medina, 1986; Vicario et al., 1991; Vicario and Medina, 1992) and suckling rats (Dombrowski et al., 1989; Itoh and Quastel, 1970), in newborn dogs (Hellmann et al., 1982) and in glucose-6-phosphatase-deficient human babies (Fernandes et al., 1984).

Renal Cysts and Associated Malformations in Pediatric Autopsy Material

Autosomal recessive polycystic kidney disease (ARPKD), also known as infantile polycystic kidney disease (or Potter type I), and autosomal dominant polycystic kidney disease (ADPKD), an adult form of polycystic kidney disease (or Potter type III), are the two main types of genetic polycystic kidney diseases encountered in infants and children. The clinical spectrum of ARPKD is variable, however, it presents mainly in infancy and most affected viable neonates die within the first few hours of extrauterine life. Some of the clinical variability is accounted for by differences in the genotypes responsible for the clinical syndrome of ADPKD. At least three different gene codes for the development of ADPKD have been identified, with loci mapped to chromosome 16 (polycystic kidney disease or PKD1), 1,2 to chromosome 4 (PKD2), 3 and recently a small number of families with ADPKD that are not linked to the PKD1 and PKD2 loci. 4,5 A single ARPKD gene is identified and is linked to chromosome 6. 6 The morphologic criteria applied to make distinctions among the different types of chronic renal disease (CRD) involve the cyst size, number, cyst distribution within the kidney, the site along the nephron from which the cysts arise, and the possible involvement of other organs. CRD may present as a non-syndromal heritable and sporadic form, or as a component of a malformation syndrome. 7 The aim of this study was to determine the relative frequency of the different types of CRD, and to study the frequency of associated extrarenal disorders and congenital malformations. In this report, we emphasize the latter as an important consideration in cases presenting in the neonatal period.

Inferior pharyngeal constrictor electromyographic activity during permeability pulmonary edema in lambs.

Newborn mammals exhibit an active expiratory upper airway closure during the first hours of extrauterine life. We have recently shown that permeability pulmonary edema led to active expiratory glottic closure in awake newborn lambs while hypoxia (inspired O2 fraction 8%; 15 min) did not. In the present study, we tested the hypothesis that expiratory glottic closure was accompanied by an increase in pharyngeal constrictor muscle expiratory electromyographic (EMG) activity. We studied seven awake nonsedated lambs aged 8-20 days. Airflow (facial mask + pneumotachograph), blood gases (arterial catheter), and EMG activity of both the thyroarytenoid muscle (a glottic adductor) and the inferior pharyngeal constrictor muscle were recorded before and after intravenous injection of halothane (0.05 ml/kg) to induce a permeability pulmonary edema. A central apnea (duration 15 s to 5 min) with continuous thyroarytenoid and inferior pharyngeal constrictor activity was observed within seconds after halothane injection. One lamb died despite rescuing maneuvers. An expiratory phasic thyroarytenoid and inferior pharyngeal constrictor muscle activity with simultaneous zero airflow gradually took place and, by 30 min after halothane injection, was present at each expiration in the six remaining lambs. Expiratory glottic and pharyngeal constrictor muscle EMG activity was subsequently present during the whole study period (1.5-5 h), even after correction of the initial hypoxia. Permeability lung edema was present at postmortem examination in all seven lambs. We conclude that a permeability pulmonary edema induced by intravenous halothane in non-sedated lambs enhances both glottic and pharyngeal constrictor muscle expiratory EMG. We hypothesize that expiratory contraction of the inferior pharyngeal constrictor muscle could participate in the active expiratory upper airway closure; this, in turn, might improve alveolocapillary gas exchange by increasing the end-expiratory lung volume.

Intraalveolar bubbles and bubble films I. Formation and development during the first 48 hours of extrauterine life in rabbits

Background Aeration of mature lungs at birth depends on formation of intraalveolar bubbles and bubble films (Scarpelli 1978. Pediatr. Res., 12:1070–1076). Bubbles establish immediately structural stability and pulmonary gas exchange. Given that air spaces are cleared in minutes of fetal liquid (the initial substrate for bubble formation), is formation possible beyond this period? If so, is this related to early development of pulmonary function and structure? Methods Mature, spontaneously breathing rabbit pups at 1–10 min and 1, 3, 8, 24, and 48 h after vaginal birth were anesthetized, trachea was occluded at “resting volume” (≅ functional residual capacity), and lungs were rapidly exposed to preserve in vivo intrapulmonary status. The entire lung was examined by stereomicroscopy. Other determinations included resting volume, lung wet weight, volume-pressure curves, histological sections, lung dry weight, tissue hydroxyproline (OH-Pro), and lavage phospholipids (PL). Bubble mobility in situ was tested. Bubbles were released into bathing liquid by incision of peripheral units and monitored over time. Results Pup activity and gross appearance of the lungs, together with septal thinning, secondary septal development, clearance of intraluminal liquid, increasing tissue OH-Pro, and PL distribution indicated normal postnatal development. Each aerated unit examined at resting volume (all lobes, all ages) contained intraalveolar bubbles. Transition to free gas exclusively in conducting airways and bubbles/bubble films in peripheral gas exchange units occurred within 1 h. Bubbles appeared to be exclusively within alveoli at 4 h and thereafter. Bubbles persisted and new bubbles were formed during subsequent inflation to maximal volume and deflation to atmospheric pressure (P0). Volume of intact lungs at P0 was maintained by the counterforce of rigid bubble films against tissue retraction. When bubbles were released either at resting volume or at P0, the bubble-free loci became airless. Constant size and stability of released bubbles support preferential incorporation of surfactants into bubble films and constant “near-zero surface tension” (Scarpelli 1978. Pediatr. Res., 12:1070–1076). Conclusions We show the ubiquitous presence of intraalveolar bubbles and bubble films in vivo throughout the first 48 h of postnatal life. Bubble film rigidity sustains aeration and prevents collapse, while low surface tension of the films facilitate liquid removal from the air spaces. Bubbles in situ are stable and, within apparent limits, mobile; after birth they are quickly restricted to the alveolar spaces, leaving airways bubble free. © 1996 Wiley-Liss, Inc.

Intraalveolar bubbles and bubble films. I. formation and development during the first 48 hours of extrauterine life in rabbits.

Aeration of mature lungs at birth depends on formation of intraalveolar bubbles and bubble films (Scarpelli 1978. Pediatr. Res., 12:1070-1076). Bubbles establish immediately structural stability and pulmonary gas exchange. Given that air spaces are cleared in minutes of fetal liquid (the initial substrate for bubble formation), in formation possible beyond this period? If so, is this related to early development of pulmonary function and structure? Mature, spontaneously breathing rabbit pups at 1-10 min and 1, 3, 8, 24, and 48 h after vaginal birth were anesthetized, trachea was occluded at "resting volume" (approximately functional residual capacity), and lungs were rapidly exposed to preserve in vivo intrapulmonary status. The entire lung was examined by stereomicroscopy. Other determinations included resting volume, lung wet weight, volume-pressure curves, histological sections, lung dry weight, tissue hydroxyproline (OH-Pro), and lavage phospholipids (PL). Bubble mobility in situ was tested. Bubbles were released into bathing liquid by incision of peripheral units and monitored over time. Pup activity and gross appearance of the lungs, together with septal thinning, secondary septal development, clearance of intraluminal liquid, increasing tissue OH-Pro, and PL distribution indicated normal postnatal development. Each aerated unit examined at resting volume (all lobes, all ages) contained intraalveolar bubbles. Transition to free gas exclusively in conducting airways and bubbles/bubble films in peripheral gas exchange units occurred within 1 h. Bubbles appeared to be exclusively within alveoli at 4 h and thereafter. Bubbles persisted and new bubbles were formed during subsequent inflation to maximal volume and deflation to atmospheric pressure (P0). Volume of intact lungs at P0 was maintained by the counterforce of rigid bubble films against tissue retraction. When bubbles were released either at resting volume or at P0, the bubble-free loci became airless. Constant size and stability of released bubbles support preferential incorporation of surfactants into bubble films and constant "near-zero surface tension" (Scarpelli 1978. Pediatr. Res., 12:1070-1076). We show the ubiquitous presence of intraalveolar bubbles and bubble films in vivo throughout the first 48 h of postnatal life. Bubble film rigidity sustains aeration and prevents collapse, while low surface tension of the films facilitate liquid removal from the air spaces. Bubbles in situ are stable and, within apparent limits, mobile; after birth they are quickly restricted to the alveolar spaces, leaving airways bubble free.

Endocrine changes during the first four hours of extra-uterine life of lambs as related to body weight and rectal temperatures

In order to examine postpartum (pp) changes of concentrations of thyroid stimulating hormone (TSH), thyroxine (T 4), triiodothyronine (T 3), reverse triiodothyronine (rT 3), growth hormone (GH) and cortisol (C) in newborn lambs, blood samples were taken at birth, 1, 2, and 4 h pp. Plasma TSH and T 4 remained unchanged during this early postnatal period. A significant increase of T 3 was observed at 1 h pp, while a continuous decrease in rT 3 and GH was found during the 4-period. C decreased sharply at 1 h pp and remained stable from 1 to 4 h pp. Rectal temperatures (rt) were increased significantly ( P<0.005) at 1 h pp and did not change during the following 3 h. In a second part of the experiment, blood sampling was performed once only at birth in order to determine correlations between the different hormones, rt and body weight (BW), respectively, in twins and triplets. Absence of strong correlations between thyroid hormones, BW and rt, and results of factor analyses indicate that thyroid hormone levels at birth are not related to rt or BW and hence not to survival chances of lambs, either twins or triplets.

Insulin and Glucagon during the Perinatal Period: Secretion and Metabolic Effects on the Liver

Insulin and glucagon are detected in the plasma of most species early in gestation. In the fetus at term, insulin and glucagon secretion can be modified by long-term changes in glucose concentration but the responsiveness of A and B cells to glucose is lower than in the adult. The plasma insulin/glucagon molar ratio is high in the fetus at term, then decreases dramatically immediately after birth and remains low during the first hours of extrauterine life. This situation results in favored hepatic glycogen storage and prevented gluconeogenesis in utero, and sharp glycogen breakdown and active gluconeogenesis during the early postnatal period.

Perinatal heart rate variability and circulatory adaptation in association with normal labor and after elective cesarean section

Heart rate variability and basal hemodynamic parameters were studied in connection with 20 normal deliveries and after 16 elective cesarean sections. Eight of the cesarean sections were performed with the use of maternal barbiturate anesthesia and eight with the use of epidural blockade. The interval index describing the long-term variability and the differential index describing the short-term variability of the heart rate were measured continuously from 10-minute samples of a direct fetal electrocardiogram and a neonatal electrocardiogram of the infants by a microprocessor-based system. In association with normal labor, significant increases in both indices of variability were observed during the second stage of labor and during the first 2 hours of extrauterine life. After elective cesarean section both indices of neonatal heart rate variability remained significantly lower than those after normal labor. However, a significant increase was observed in the differential index of the infants delivered with the use of epidural blockade. During the neonatal period, simultaneous recordings of basal heart rate, systolic and diastolic blood pressures, and rectal and heel temperatures were made at 10-minute intervals. The basal neonatal heart rate was significantly higher in both cesarean section subgroups compared with that after normal labor. A significant decrease in basal neonatal heart rate during the second hour of life was observed after normal labor and after cesarean section with the use of epidural blockade. Systolic blood pressures in newborn infants delivered with the use of maternal epidural blockade were equal to those after normal labor, but higher than those after cesarean section with barbiturate anesthesia. Newborn infants after elective cesarean section had significantly lower diastolic blood pressures than infants delivered normally, but there was no difference in the diastolic blood pressures between the two cesarean section subgroups. The infants delivered vaginally had lower heel temperatures than those delivered abdominally. According to the present study, the neonatal circulatory adaptation after elective cesarean section is different from that after normal delivery; however, the neonatal hemodynamics after cesarean section with epidural blockade more closely resemble the situation after normal labor.

Inhibition of Glucagon Secretion in the Human Newborn by Glucose Infusion

Plasma glucagon, serum insulin, and blood glucose responses during a 30-min glucose (1 g/kg body wt) or saline infusion were reported in 37 full-term and 35 preterm infants. They were studied either on the first day of life before feeding was initiated or during the first week of life. Glucose infusion promptly suppressed glucagon secretion in all infants even from the initial hours of extrauterine life. The mean maximal decrement in percentage in the full-term infants on the day of birth and older was 54 +/- 4% and 61 +/- 6%, respectively, while the maximal decrement in the preterm infants on day of birth and older was significantly lower (44 +/- 3% and 38 +/- 4%, respectively). The insulin response to glucose was variable in all infants and most of them showed a delayed rise of serum insulin. No change in plasma glucagon, blood glucose, and serum insulin was observed during and after saline infusion.

Coagulation changes in the newborn with respiratory failure

These studies involved clinical and laboratory investigations in 24 infants. Eleven healthy premature and term babies were used to establish a normal laboratory range. Thirteen consecutive infants requiring ventilatory assistance were compared to the normal group according to a broad range of clinical and laboratory measurements. Clinical parameters of the two groups were obviously different. However, the laboratory measurements of clotting appears to be close in each group only within the first 12 hours of extrauterine life. The fibrinolytic system appeared to be the most significantly activated parameter as seen by the initial deviations of the plasminogen and fibrin split products in the ill infants. Related changes in complement C′3 and C′4 were also noted. Two of the study infants survived and their data is shown for prognostic purposes. The earliest results that appeared to discriminate between survivors and fatalities were the plasminogen levels at 12 to 24 hours. We conclude from these data that activation of coagulation, fibrinolytic, and complement systems occurs in all newborns with respiratory failure and is detectable in their laboratory measurements.

Pharmacokinetics of oxazepam given during labour*

The transfer across the placenta and the maternal and neonatal kinetics of oxazepam and its conjugate was studied in 12 patients and their newborns. Oxazepam was readily absorbed and peak plasma concentrations were similar to those in healthy non-pregnant volunteers. When meperidine was given within one hour of the dose of oxazepam the absorption was delayed but the bioavailability did not decrease. In the newborns the umbilical vein plasma concentration of oxazepam usually exceeded that of the conjugate. The reverse was true for all subsequent plasma samples from the newborn. The half-life of oxazepam in the newborn averaged 22 hours as compared to 6.5 hours in the mothers. A significant rise of the plasma concentration of oxazepam conjugate was noted in three newborns during the first 6-10 hours of extrauterine life. This shows that the newborn is able to conjugate oxazepam. The Apgar score values were normal.