Neonatal Transitional Physiology: A New Paradigm

Early clamping of the umbilical cord at birth, a practice developed without adequate evidence, causes neonatal blood volume to vary 25% to 40. Such a massive change occurs at no other time in one\u27s life without serious consequences, even death. Early cord clamping may impede a successful transition and contribute to hypovolemic and hypoxic damage in vulnerable newborns. The authors present a model for neonatal transition based on and driven by adequate blood volume rather than by respiratory effort to demonstrate how neonatal transition most likely occurs at a normal physiologic birth

The prevalence of atrial fibrillation in Greenland:a register-based cross-sectional study based on disease classifications and prescriptions of oral anticoagulants

    Previous studies of the prevalence of atrial fibrillation (AF) in Greenland are based on either single-point electrocardiograms (ECGs) or patients admitted with stroke. This study estimates the prevalence of AF based on disease classifications in the electronic medical record system (EMR) and prescriptions of oral anticoagulants (OACs). Patients given a diagnose classification code for AF or atrial flutter or prescribed the vitamin K antagonist Warfarin or the direct-acting oral anticoagulant Rivaroxaban were identified in the EMR. Descriptive data and selected laboratory values were extracted, and a minimum CHA(2)DS(2)-VASc score was calculated for the 790 patients identified in the EMR (66% men). A total prevalence of AF of 1.4% was found in the general population (1.8% among men and 1.0% among women), with a significantly lower prevalence among women younger than 70 years. There was a significant increase in AF-prevalence with advancing age (p<0.001) for both men and women. A minimum CHA(2)DS(2)-VASc was estimated and app. 10% of the patients may be undertreated with OACs. The prevalence of AF found in this study is higher than that found in previous studies in Greenland and comparable to the prevalence found in other Western countries, indicating that AF is common in Greenland

Relational Fusion Networks: Graph Convolutional Networks for Road Networks

The application of machine learning techniques in the setting of road networks holds the potential to facilitate many important intelligent transportation applications. Graph Convolutional Networks (GCNs) are neural networks that are capable of leveraging the structure of a network. However, many implicit assumptions of GCNs do not apply to road networks. We introduce the Relational Fusion Network (RFN), a novel type of GCN designed specifically for road networks. In particular, we propose methods that outperform state-of-the-art GCNs by 21%-40% on two machine learning tasks in road networks. Furthermore, we show that state-of-the-art GCNs may fail to effectively leverage road network structure and may not generalize well to other road networks.Comment: IEEE Transactions on Intelligent Transportation Systems (2020). arXiv admin note: substantial text overlap with arXiv:1908.1156

Cardiac asystole at birth: Is hypovolemic shock the cause?

A birth involving shoulder dystocia can rapidly deteriorate—from a fetus with a reassuring tracing in the minutes before birth, to a neonate needing aggressive resuscitation. Infants experiencing a traumatic birth involving shoulder dystocia may be severely compromised, even when the preceding labor was uncomplicated. This paper presents two cases in which infants had normal heart beats recorded 5–10 min before birth and were born with cardiac asystole following shoulder dystocia. Often, in cases of shoulder dystocia, infants shift blood to the placenta due to the tight compressive squeeze of the body in the birth canal (along with cord compression) and thereby may be born hypovolemic. Our hypothesis is that the occurrence of sudden cardiac asystole at birth is due to extreme hypovolemic shock secondary to the loss of blood. At birth, the sudden release of pressure on the infant’s body results in hypoperfusion resulting in low central circulation and blood pressure. Severe hypovolemic shock from these effects leads to sudden cardiac arrest. Immediate cord clamping maintains the hypovolemic state by preventing the physiologic and readily available placental blood from returning to the infant. Loss of this blood initiates an inflammatory response leading to seizures, hypoxic-ischemic encephalopathy, and brain damage or death. Animal studies have shown that human umbilical stem cells injected into a rat’s abdomen after induced brain damage, can protect the rat’s brain from developing permanent injury. To prevent damage to newborns, the infant must receive the blood volume and stem cells lost at the time of descent and immediate cord clamping. Recommended countermeasures for research include: (1) resuscitation at the perineum with intact cord; or (2) milking the cord before clamping; or (3) autologous transfusion of placenta blood after the birth; or (4) rapid transfusion of O negative blood after birth and before seizures begin

Nuchal Cord Management and Nurse-Midwifery Practice

Nuchal cord, or cord around the neck of an infant at birth, is a common finding that has implications for labor, management at birth, and subsequent neonatal status. A nuchal cord occurs in 20% to 30% of births. All obstetric providers need to learn management techniques to handle the birth of an infant with a nuchal cord. Management of a nuchal cord can vary from clamping the cord immediately after the birth of the head and before the shoulders to not clamping at all, depending on the provider\u27s learned practices. Evidence for specific management techniques is lacking. Cutting the umbilical cord before birth is an intervention that has been associated with hypovolemia, anemia, shock, hypoxic-ischemic encephalopathy, and cerebral palsy. This article proposes use of the somersault maneuver followed by delayed cord clamping for management of nuchal cord at birth and presents a new rationale based on the available current evidence

Experimental Demonstration of Squeezed State Quantum Averaging

We propose and experimentally demonstrate a universal quantum averaging process implementing the harmonic mean of quadrature variances. The harmonic mean protocol can be used to efficiently stabilize a set of fragile squeezed light sources with statistically fluctuating noise levels. The averaged variances are prepared probabilistically by means of linear optical interference and measurement induced conditioning. We verify that the implemented harmonic mean outperforms the standard arithmetic mean strategy. The effect of quantum averaging is experimentally tested both for uncorrelated and partially correlated noise sources with sub-Poissonian shot noise or super-Poissonian shot noise characteristics.Comment: 4 pages, 5 figure