Bruxellas, Belgium

Physiologically Based Cord Clamping To Improve Neonatal Outcomes In Moderate And Late Preterm Newborns

The successful transition from fetal to neonatal life is a major physiological challenge that requires the coordination of lung developmental processes, which culminate with the formation of a diffusible alveolar-capillary barrier, adequate pulmonary vasoreactivity, mature surfactant system, and clearance of lung fluid. During fetal life, gas exchange does not take place in fetal lungs but in the placenta. High pulmonary vascular resistance diverts blood flow to the left atrium through the foramen ovale and to the aorta via the ductus arteriosus. The placental circulation receives 30-50 % of the fetal cardiac output and is the major source of venous return to the fetal heart. Therefore, the umbilical venous return determines the preload for the left ventricle. Shortly before birth and during labor, the lungs undergo important transitional changes. The reabsorption of lung fluid within the airways is initiated during labor by adrenaline-induced activation of sodium channels. Uterine contractions during labor and the onset of inspiration after umbilical cord clamping generate a high transpulmonary pressure gradient leading to additional clearance of fluid from the airways into the surrounding tissue . Following the first breath and lung aeration, oxygen-induced vasodilation leads to a sudden rise in pulmonary blood flow and left atrial pressures, which closes the foramen ovale. Meanwhile, systemic vascular resistance increases above the level of pulmonary vascular resistance after placental removal, which reverses blood flow across the ductus arteriosus and induces ductal closure in response to high oxygen tension. Premature birth can impact the success of adaptation to extrauterine life. Moderately preterm and late preterm births represented 4.4% of singleton live births in the Brussels area in 2020. Although they may be close to term, the loss of the last 4 to 8 weeks of gestation is vital to their physiologic and metabolic maturity. Because of their physiologic and metabolic immaturity, they have higher morbidity and mortality rates compared with term infants (gestational age 37 weeks). Although they may look similar to full-term infants, especially for the late preterm, the gap in the last few weeks of gestation is critical for physiological and metabolic maturation. Moderate and late preterm infants are at higher risk than term infants for a number of neonatal complications. This includes respiratory distress requiring non invasive or invasive ventilation, transient tachypnea of the newborn, intraventricular hemorrhage, periventricular leukomalacia, bacterial sepsis, apnoea, hypoglycemia, temperature instability, jaundice and hyperbilirubinaemia, feeding difficulties, neonatal intensive care admission, and also death. By contrast with lung's full-term newborn, lung of the preterm newborn presents an inability to adapt to extra-uterine life. Lung development at this time of gestation is in the saccular stage. Because of this immature lung structure, it results in delayed intrapulmonary fluid absorption, surfactant deficiency and inefficient gas exchange leading to respiratory morbidities such as transient tachypnea of the newborn, respiratory distress syndrome, persistent pulmonary hypertension. In addition, synchronicity and breath control is also immature and leads to apnea. These newborns exhibit a higher risk of positive pressure ventilation resuscitation at birth, admission to the neonatal intensive care unit (NICU), and severe hypoxic respiratory failure requiring mechanical ventilation in the most severe cases. In addition to increased neonatal morbidity, moderate or late preterm birth can impact mother-infant relationship. After delivery, immediate skin-to-skin contact during the first minute after birth is the natural process recommended to support mother-infant bonding and promote early onset of breastfeeding. Despite efforts made to start skin-to-skin contact as early as possible after delivery, immediate contact is practically difficult to implement related to the need for respiratory support for most of these newborns with incomplete transition to extrauterine life. In our institution, the infant is usually separated from the mother after umbilical cord clamping to provide first care by a pediatrician before returning on the mother's chest or on the father/partner's chest depending on parental wishes and maternal well-being during the operation and only if the condition of the newborn allows it. The separation between the mother and her newborn can be further extended in the case of NICU admission for various and multiple reasons related to prematurity. The timing of umbilical cord clamping can profoundly affect the process of neonatal cardiorespiratory transition. Immediate cord clamping reduces the venous return to the heart, which transiently decreases heartbeats, cardiac output and cerebral blood flow before respiration initiates and pulmonary blood flow increases. Delayed cord clamping for longer than 60 seconds improves the transfusion of blood from the placenta to the newborn. Moreover, it can increase neonatal hemoglobin levels, improve long-term iron stores, and improve neurodevelopmental outcomes. Nevertheless, in both clinical research setting and daily practice, delayed cord clamping lasts rarely more than one minute during cesarean section. More recently, another approach, referred to as physiologically based cord clamping (PBCC), has been proposed to delay cord clamping up to 5 minutes after the onset of ventilation. PBCC allows to start lung aeration while on placental support and, therefore, promotes hemodynamic transition by increasing pulmonary blood flow and maintaining left ventricle preload. This strategy has been demonstrated efficient in preterm lambs and is feasible in very preterm infants, via the use of a purpose-designed resuscitation table that allows delayed cord clamping, maintenance of body temperature, and concomitant respiratory support where necessary. First experience has reported good parental acceptance of the procedure. Because PBCC has not been reported in moderate and late preterm infants, the present project aims to assess whether PBCC in moderate and late preterm infants would not be inferior to standard umbilical cord clamping with regards to adaptation to extrauterine life, respiratory morbidity, quality of mother-infant bonding, and maternal safety.

Iron Deficiency in Pediatric Heart Surgery

Physiologically Based Cord Clamping To Improve Neonatal Outcomes After Elective Cesarean Delivery

The successful transition from fetal to neonatal life is a major physiological challenge that requires the coordination of lung developmental processes, which culminate with the formation of a diffusible alveolar-capillary barrier, adequate pulmonary vasoreactivity, mature surfactant system, and clearance of lung fluid. During fetal life, gas exchange does not take place in fetal lungs but in the placenta. High pulmonary vascular resistance diverts blood flow to the left atrium through the foramen ovale and to the aorta via the ductus arteriosus. The placental circulation receives 30-50 % of the fetal cardiac output and is the major source of venous return to the fetal heart. Therefore, the umbilical venous return determines the preload for the left ventricle. Shortly before birth and during labor, the lungs undergo important transitional changes. The reabsorption of lung fluid within the airways is initiated during labor by adrenaline-induced activation of sodium channels. Uterine contractions during labor and the onset of inspiration after umbilical cord clamping generate a high transpulmonary pressure gradient leading to additional clearance of fluid from the airways into the surrounding tissue . Following the first breath and lung aeration, oxygen-induced vasodilation leads to a sudden rise in pulmonary blood flow and left atrial pressures, which closes the foramen ovale. Meanwhile, systemic vascular resistance increases above the level of pulmonary vascular resistance after placental removal, which reverses blood flow across the ductus arteriosus and induces ductal closure in response to high oxygen tension. The route of delivery can impact the success of adaptation to extrauterine life. Over the past 30 years, the rate of cesarean deliveries has increased worldwide. In Belgium, this can be as high as 20% of all deliveries. A subset of cesarean deliveries is scheduled in term infants in the absence of spontaneous labor when vaginal delivery is considered as too risky for maternal and/or child health. The so-called iterative cesarean delivery, which is usually considered as a routine and harmless option, can however alter neonatal health. By contrast with vaginal delivery, infants born at term by iterative cesarean delivery have to adapt despite larger volumes of fluid within airways and interstitial tissue resulting from a limited rise in transpulmonary pressure and adrenaline-induced fluid reabsorption. Subsequently, the retention of lung fluid is responsible for transient tachypnea of the newborn, a respiratory distress that is usually considered as mild, transient, and without sequelae. Moreover, infants born by elective cesarean delivery exhibit a higher risk of positive pressure ventilation resuscitation at birth, admission to the neonatal intensive care unit (NICU), and severe hypoxic respiratory failure requiring mechanical ventilation in the most severe cases. In addition to increased neonatal morbidity, iterative cesarean section can impact mother-infant relationship. After vaginal delivery, immediate skin-to-skin contact during the first minute after birth is the natural process recommended to support mother-infant bonding and promote early onset of breastfeeding. Despite efforts made to start skin-to-skin contact as early as possible after cesarean delivery, immediate contact is practically difficult to implement. In our institution, the infant is usually shortly separated from the mother after umbilical cord clamping to provide first care by a pediatrician before returning on the mother's chest or on the father's chest depending on parental wishes and maternal well-being during the operation. The separation between the mother and her newborn can be further extended in the case of NICU admission for transient tachypnea. Beside the route of delivery, the timing of umbilical cord clamping can profoundly affect the process of neonatal cardiorespiratory transition. Immediate cord clamping reduces the venous return to the heart, which transiently decreases heartbeats, cardiac output and cerebral blood flow before respiration initiates and pulmonary blood flow increases. Delayed cord clamping for longer than 60 seconds improves the transfusion of blood from the placenta to the newborn. Moreover, it can increase neonatal hemoglobin levels, improve long-term iron stores, and improve neurodevelopmental outcomes. Nevertheless, in both clinical research setting and daily practice, delayed cord clamping lasts rarely more than one minute during cesarean section. More recently, another approach, referred to as physiologically based cord clamping (PBCC), has been proposed to delay cord clamping up to 5 minutes after the onset of ventilation. PBCC allows to start lung aeration while on placental support and, therefore, promotes hemodynamic transition by increasing pulmonary blood flow and maintaining left ventricle preload. This strategy has been demonstrated efficient in preterm lambs and is feasible in very preterm infants, via the use of a purpose-designed resuscitation table that allows delayed cord clamping, maintenance of body temperature, and concomitant respiratory support where necessary. First experience has reported good parental acceptance of the procedure. Because PBCC has not been reported in term infants at risk of respiratory distress after birth, the present project aims to assess whether PBCC in term infants born by elective cesarean section would not be inferior to standard umbilical cord clamping with regards to adaptation to extrauterine life, respiratory morbidity, quality of mother-infant bonding, and maternal safety.

Study to Evaluate the Efficacy, Safety, and Tolerability of an Anti-MTBR Tau Monoclonal Antibody (BMS-986446) in Participants With Early Alzheimer's Disease

Changes in Pulmonary Ventilation Distribution Assessed by Electrical Impedance Tomography in Healthy Children Under General Anesthesia

Safety and Efficacy of MSC-EVs in the Prevention of BPD in Extremely Preterm Infants

Bronchopulmonary Dysplasia (BPD) is a chronic severe multifactorial respiratory disease that affects extremely premature infants and is the most common and severe consequence of preterm birth. BPD is associated with disrupted alveolarization and microvascular development, resulting in abnormal gas exchange and lung mechanics. BPD has a multifactorial aetiology, with pre-, peri-, and postnatal mechanisms causing inflammation and injury and resulting in the disruption of the lung's development with the insurgence of an aberrant repair mechanism. EXOB-001 consists of a population of EVs smaller than 0.22 μm in diameter, containing proteins and nucleic acids, enclosed in a double layer of phospholipids with integral and surface-bound proteins as the main components. EVs exert anti-inflammatory and immunomodulatory activity by reducing the release of proinflammatory cytokines and reducing the recruitment of immune cells in the lung. Current evidence shows that EVs can modulate macrophage phenotype, and this is relevant for BPD, because of the role macrophages have in its pathogenesis. Two hundred sixty-five (265), 40 in phase 1 (to reach 36 evaluable subjects) + 225 in phase 2 (to reach 203 evaluable subjects), extremely preterm infants at risk of developing BPD with 23 weeks up to 28 (27 weeks+6 days) weeks of gestational age and birth weight between 500g and 1,500g and being endotracheally intubated between postnatal day 3 and day 10 receiving mechanical ventilation with FiO2 > 25%. Phase 1 will start with cohorts with a single administration starting with a low dose up to a high dose and thereafter start the escalation of cohorts with 3 administrations starting with a low dose up to a high dose. In the case of 3 endotracheal administrations, there will be a window of 24 hours between the administrations (the maximal duration of the treatment with EXOB-001 will be 48 hours). Phase 2 includes 2 groups with selected dosage levels and regimen of EXOB-001 based on phase 1 interim results. Subjects will be randomised (2:2:1) to receive either EXOB-001 or placebo (saline solution).

Aortopathy Relationship to Imagery and Kinocardiography Features (ARTIK)

Aortic valve disease (AVD) is a common but under-diagnosed disease which can cause various cardiovascular complications. AVD, including aortic stenosis and aortic regurgitation, can be associated with dilatation of the ascending thoracic aorta as a result of hemodynamic mechanisms and genetic predisposition. In the assessment of an AVD, it is important to consider if it is associated with a thoracic aortic aneurysm (TAA), and vice versa. The prevalence of TAA in the general population is difficult to assess because most patients are asymptomatic, and their lethal complications (rupture and dissections) are often misdiagnosed as myocardial infarctions. The insidious evolution of aortic pathology motivates physicians to make the diagnosis as early as possible before the appearance of irreversible lesions causing significant morbidity and mortality. Traditional semiology can be useful for AVD screening (auscultation of a murmur, or observation of some visible semiological signs). However, it relies on the proficiency of care providers and may not allow a timely diagnosis of less severe forms of the disease. Moreover, imaging techniques used in current clinical practice are not appropriate for the organization of large-scale screening in asymptomatic patients. In addition, none of these techniques are accessible for the people living far away from a healthcare institution. Kinocardiography (KCG) is a portable measurement technique developed to estimate cardiac mechanical performance by studying the vibrations produced by myocardial contraction during each heartbeat and transmitted to the body surface. Signals are recorded thanks to a sensor placed on the sternum, another sensor placed on the lower back and electrocardiogram electrodes. Smartphones are equipped with accelerometers and gyroscope, and may allow anyone to measure their own cardiac mechanical function similarly to KCG. Phonocardiography (PCG) enables the detailed recording and analysis of heart sounds produced by the blood flow during the opening and closing of heart valves thanks to a microphone. It allows the extraction of heart sound information that reveals valvular diseases, such as the timing of heart valve closure, the frequency content of heart sounds, and the presence of diastolic or systolic murmurs. Video image processing by Remote photoplethysmography (RPPG) or by Eulerian video magnification (EVM) allow the analysis of color changes and movements, invisible to the naked eye. The primary objective of this prospective observational study is to better understand and assess KCG signals modifications due to aortic valve disease (AVD) and/or thoracic aortic aneurysm (TAA). It will be possible thanks to imaging techniques such as 4D flow MRI, and thanks to a comparison with PCG. The secondary objective of our study is to evaluate if a smartphone can be used for the diagnostic and characterization of AVD, using KCG, PCG or video image processing. The possible participants will be identified, according to inclusion/exclusion criteria. Informed consent will be given to the patients. Immediately after the echocardiography and/or the cardiac MRI, the investigators will record KCG and PCG data, and then perform similar measurements using a smartphone placed on the torso. These measurements are followed by two short video recordings of 30 seconds, simultaneously to a KCG recording. For patients undergoing aortic valve replacement or thoracic aortic aneurysm surgery, the investigators will also perform the KCG measurements post-operatively, immediately after de post-operative cardiac MRI and/or echocardiography.

Complications of High Frequency Jet Ventilation

Use of Long-Acting Injectable Cabotegravir/Rilpivirine for the Treatment of HIV in Belgium