Seminars in Perinatology RSS feed: Current Issue. The purpose of each issue of Seminars in Perinatology is to provide authoritative and comprehensive reviews of a single topic of interest to professionals who care for the mother, the fetus, and the newborn. The journal's readership includes perinatologists, obstetricians, pediatricians, epidemiologists, students in these fields, and others. Each issue offers a comprehensive review of an individual topic, with emphasis on new developments that will have a direct impact on their practice. 2012 Topics , Volume 36 Maternal Mortality Washington C. Hill, MD, FACOG Patent Ductus Arteriosus: Mechanisms and Management Jeff Reese, MD Multiple Gestations Karin Fuchs, MD, and Russell Miller, MD Transfusion Practices in the Neonate Edmund LaGamma, MD Infections in the Neonate Matthew Bizzarro, MD http://www.seminperinat.com/?rss=yesElsevier Inc.en © 2012 Published by Elsevier Inc. All rights reserved. Seminars in Perinatology0146-0005362April 2012 © 2012 Published by Elsevier Inc. All rights reserved. healthpermissions@elsevier.comhttp://www.seminperinat.com/article/PIIS014600051200002X/abstract?rss=yesCover10.1053/S0146-0005(12)00002-XSeminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-3OFCOFChttp://www.seminperinat.com/article/PIIS0146000512000031/abstract?rss=yesMasthead10.1053/S0146-0005(12)00003-1Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-3IFCIFChttp://www.seminperinat.com/article/PIIS0146000512000055/abstract?rss=yesTable of Contents10.1053/S0146-0005(12)00005-5Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-3iihttp://www.seminperinat.com/article/PIIS0146000512000043/abstract?rss=yesTopics10.1053/S0146-0005(12)00004-3Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-3iiiihttp://www.seminperinat.com/article/PIIS0146000511001637/abstract?rss=yesThe ductus arteriosus occupies a unique position in the history of medicine. The presence of a fetal vascular conduit interconnecting the aorta and the main pulmonary artery was originally recognized by Galen in the 2nd century a.d. and recorded in his anatomic compendia. Galen and other early anatomists formed erroneous conclusions about the fetal and adult circulation. However, their description of ductus closure after birth and the belief that blood was aerated in the placenta, along with passage between the portal and caval system and transmission into the aorta with bypass of the unexpanded fetal lung, indicate the longevity of our awareness of the ductus from medical antiquity.Patent Ductus Arteriosus: Mechanisms and ManagementJeff Reese10.1053/j.semperi.2011.09.017Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-38991http://www.seminperinat.com/article/PIIS0146000511001649/abstract?rss=yes Closure of the ductus arteriosus at birth is a complex phenomenon being conditioned by antenatal events and progressing in preprogrammed steps. Functional at first, narrowing of the vessel is determined by 2 overlapping processes—removal of the prostaglandin E2-based relaxation sustaining prenatal patency and activation of a constrictor mechanism by the natural rise in blood oxygen tension. Two schemes have been proposed for oxygen action—one involving a cytochrome P450 hemoprotein (sensor)/endothelin-1 (effector) complex and the other a set of voltage-gated K+ channels. These proposals, however, are not mutually exclusive. Structural closure follows the constriction through a remodeling process initiated antenatally with the development of intimal cushions and completed postnatally by a host of humoral and mechanical stimuli. Research in this area has already provided clinical applications. Nevertheless, management of premature infants with persistent ductus remains troublesome and calls for an alternative approach to the prostaglandin E2 inhibitors now in use. Studies in progress on the oxygen-sensing system may lead to a definitive solution for this problem. Mechanisms for Ductus Arteriosus ClosureFlavio Coceani, Barbara Baragatti10.1053/j.semperi.2011.09.018Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-39297http://www.seminperinat.com/article/PIIS0146000511001650/abstract?rss=yes The ductus arteriosus is a vital fetal structure designed to close shortly after birth. Although many physiologic and pharmacologic investigations have characterized the closure of this structure, genetic studies of persistent patency of the ductus arteriosus (patent ductus arteriosus, PDA) are relatively recent. Progress in the identification of specific genes associated with PDA is well behind that of many adult-onset diseases because of several reasons ranging from the lack of large biorepositories for this unique population to the belief that any genetic contribution to PDA is minimal. Viewing the PDA as a complex, developmentally influenced disease with both genetic and environmental risk factors has resulted in initial successes in some genetic studies. We will introduce several genetic approaches, which have been or are currently being applied to the study of PDA, that have been successful in identifying polymorphisms associated with adult diseases. Genetic investigations of PDA will be discussed with respect to heritability, in general, and to specific risk genes. Several animal models that have been used to study PDA-related genes will also be presented. Further advances in discovering genetic variation causing PDA will drive the more rational use of current therapies, and may help identify currently unknown targets for future therapeutic manipulation. Genetics of Patent Ductus Arteriosus Susceptibility and TreatmentHanine Hajj, John M. Dagle10.1053/j.semperi.2011.09.019Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-398104http://www.seminperinat.com/article/PIIS0146000511001662/abstract?rss=yes Although ongoing patency of the ductus arteriosus is common in small extremely preterm infants, consensus is lacking regarding its clinical significance and treatment strategies. Literature regarding likelihood of spontaneous closure, impact on neonatal morbidity and long-term outcomes, and adverse effects of intervention has led to uncertainty as to the best course of action. Enhancing the determination of hemodynamic significance and refining patient selection for therapeutic intervention will streamline the decision-making process. Targeted neonatal echocardiography performed by the clinician has gained popularity worldwide, and preliminary data show that it has the potential to optimize patient outcomes. We review the arguments for and against medical and surgical therapy, explore how targeted neonatal echocardiography used in conjunction with biomarkers may refine the treatment approach, and consider future directions in the field. The Ductus Arteriosus: A Refined Approach!Arvind Sehgal, Patrick J. McNamara10.1053/j.semperi.2011.09.020Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-3105113http://www.seminperinat.com/article/PIIS0146000511001674/abstract?rss=yes The current uncertainty in relation to treatment of the preterm patent ductus arteriosus reflects limitations to our understanding of the pathophysiology of ductal shunting, most particularly which ducts matter to which babies and when they matter. Doppler ultrasound offers a pragmatic tool with which to assess ductal patency and shunt significance and to allow prediction of spontaneous and therapeutic closure. Biomarkers, such as B-type natriuretic peptide, and clinical signs may have a diagnostic role where ultrasound is not available and also possibly as an adjunct to echocardiography in determining the pathophysiological impact of a ductal shunt in an individual baby. Diagnosis of the Preterm Patent Ductus Arteriosus: Clinical Signs, Biomarkers, or Ultrasound?Nick Evans10.1053/j.semperi.2011.09.021Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-3114122http://www.seminperinat.com/article/PIIS0146000511001686/abstract?rss=yes Although a moderate-sized patent ductus arteriosus (PDA) needs to be closed by the time a child is 1-2 years old, there is great uncertainty about whether it needs to be closed during the neonatal period. Although 95% of neonatologists believe that a moderate-sized PDA should be closed if it persists in infants (born before 28 weeks) who still require mechanical ventilation, the number of neonatologists who treat a PDA when it occurs in infants who do not require mechanical ventilation varies widely. Both the high likelihood of spontaneous ductus closure and the absence of randomized controlled trials, specifically addressing the risks and benefits of neonatal ductus closure, add to the current uncertainty. New information suggests that early pharmacologic treatment has several important short-term benefits for the preterm newborn. By contrast, ductus ligation, while eliminating the detrimental effects of a PDA on lung development, may create its own set of morbidities that counteract many of the benefits derived from ductus closure. Patent Ductus Arteriosus: Are Current Neonatal Treatment Options Better or Worse Than No Treatment at All?Ronald I. Clyman, James Couto, Gail M. Murphy10.1053/j.semperi.2011.09.022Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-3123129http://www.seminperinat.com/article/PIIS0146000511001698/abstract?rss=yes Over recent years, the clinical approach to patency of the ductus arteriosus in the premature neonate has been the subject of intensive reevaluation. What had once been considered inherently obvious is no longer to be taken for granted. In this review we will focus on some of the controversies surrounding various aspects of the pharmacologic treatment regimens for patent ductus arteriosus closure. The pros and cons of prophylactic vs therapeutic indomethacin, of early vs late therapy, of high- vs low-dose indomethacin, of single vs multiple courses of treatment, and of ibuprofen vs indomethacin will be considered. In addition, the possibility that patency of the ductus arteriosus is merely a physiological manifestation of extreme prematurity, and thus does not necessarily need to be therapeutically closed, has become a viable approach in some cases. As such, we will examine echocardiographic and biochemical criteria aimed at determining the clinical and hemodynamic significance of ductal shunting, and thereby of the need to treat. Finally, we speculate on potential therapeutic directions for the future, including individualized treatment regimens and multidrug treatment cocktails for those who fail initial monodrug therapy. Managing the Patent Ductus Arteriosus in the Premature Neonate: A New Look at What We Thought We KnewCathy Hammerman, Alona Bin-Nun, Michael Kaplan10.1053/j.semperi.2011.09.023Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-3130138http://www.seminperinat.com/article/PIIS0146000511001704/abstract?rss=yes Although surgical ligation of a persistent patent ductus arteriosus resolves the adverse hemodynamic consequences of the systemic-to-pulmonary shunt and may confer some long-term benefits, it is also associated with both immediate and long-term negative effects. The population that benefits from or is harmed by the procedure is not clearly defined. Although indiscriminate ligation of the patent ductus arteriosus in all patients is not supported by the available information, the recent suggestion declaring the ductus harmless is not supported either. As we await the results of appropriately designed randomized control studies to define the indications for ligation, we must use clinical and echocardiographic indicators of a hemodynamically significant ductus arteriosus and thoughtful assessment of each individual patient to help guide us in addressing this complex problem. Pros and Cons of Patent Ductus Arteriosus Ligation: Hemodynamic Changes and Other Morbidities After Patent Ductus Arteriosus LigationShahab Noori10.1053/j.semperi.2011.09.024Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-3139145http://www.seminperinat.com/article/PIIS0146000511001716/abstract?rss=yes During fetal life, the ductus arteriosus is a normal and essential structure that connects the pulmonary artery to the distal aortic arch, permitting right ventricular ejection into the aorta. After birth, with commencement of pulmonary blood flow and a 2-ventricle circulation, a variety of physiological and biochemical signals normally result in complete closure of the ductus. Persistent patency of the ductus arteriosus may impair systemic cardiac output and result in deleterious effects on the cardiovascular system and lungs. Although surgery is still the treatment of choice for most premature infants with patent ductus arteriosus (PDA), transcatheter techniques have largely supplanted surgery for closure of PDA in children and adults. This article is a review of the PDA in term infants, children, and adults, with focus on the clinical manifestations and management. The Patent Ductus Arteriosus in Term Infants, Children, and AdultsDouglas J. Schneider10.1053/j.semperi.2011.09.025Seminars in Perinatology 36, 2 (2012)2012-04-01Seminars in Perinatology2012-04-01362S0146-0005(11)X0008-3146153