Hemodynamic management of the micropreemie: When inotropes are not enough.

Managing perfusion in the micropreemie is challenging and should be guided by the patho-physiology, gestational and postnatal age of the baby, perinatal history, and the persistence of fetal shunts. The assessment should incorporate bedside tools such as blood pressure, clinical perfusion markers, and functional echocardiography. The multimodal approach to diagnose and identify the cause of hemodynamic compromise paves the way to a targeted approach to treatment. Characterizing the predominant pathophysiologic cause of low cardiac output and impaired cellular metabolism enables a more accurate use of inotropes, vasopressors, and volume support to suit a particular pathophysiologic situation.

Persistent pulmonary hypertension of the newborn: Historical perspectives.

For many decades, persistent pulmonary hypertension of the newborn (PPHN) remained a baffling disorder, often confused with cyanotic congenital heart disease, with a very high mortality. Originally described as a condition characterized by clear lung fields and profound hypoxemia, modern diagnostic techniques and novel therapeutics have improved the outcomes of affected newborns. This paper will review the historical aspects of PPHN and enable the reader to see how far we have come but also how far we have to go in conquering this unique disorder.

Medico-legal considerations in the context of neonatal encephalopathy and therapeutic hypothermia.

Neonatal encephalopathy (NE) is a significant complication of the peripartum period. It can lead to lifelong neurologic disabilities, including cerebral palsy, cognitive impairments, developmental delays, and epilepsy. Induced hypothermia is the first therapy, which has shown promise in improving the outcomes for neonates with moderate to severe NE following a presumed intrapartum insult. NE is also a frequent source of medical malpractice litigation. In this paper, we will review salient features of the American Tort System as it pertains to medical malpractice. We will discuss the obstetric medico-legal implications of therapeutic hypothermia and suggest a five-step approach to analyzing neonatal cases for causation, etiology, timing of occurrence, responsibility, and liability. We will close with three illustrative clinical cases.

New Pharmacologic Approaches to Bronchopulmonary Dysplasia.

Bronchopulmonary Dysplasia is the most common long-term respiratory morbidity of preterm infants, with the risk of development proportional to the degree of prematurity. While its pathophysiologic and histologic features have changed over time as neonatal demographics and respiratory therapies have evolved, it is now thought to be characterized by impaired distal lung growth and abnormal pulmonary microvascular development. Though the exact sequence of events leading to the development of BPD has not been fully elucidated and likely varies among patients, it is thought to result from inflammatory and mechanical/oxidative injury from chronic ventilatory support in fragile, premature lungs susceptible to injury from surfactant deficiency, structural abnormalities, inadequate antioxidant defenses, and a chest wall that is more compliant than the lung. In addition, non-pulmonary issues may adversely affect lung development, including systemic infections and insufficient nutrition. Once BPD has developed, its management focuses on providing adequate gas exchange while promoting optimal lung growth. Pharmacologic strategies to ameliorate or prevent BPD continue to be investigated. A variety of agents, to be reviewed henceforth, have been developed or re-purposed to target different points in the pathways that lead to BPD, including anti-inflammatories, diuretics, steroids, pulmonary vasodilators, antioxidants, and a number of molecules involved in the cell signaling cascade thought to be involved in the pathogenesis of BPD.

Assessment of neonatal perfusion.

Disorders of perfusion in newborn infants are frequently observed in neonatal intensive care units. The current assessment practices are primarily based on clinical signs. Significant technologic advances have opened new avenues for continuous assessment at the bedside. Combining these devices with functional echocardiography provides an in-depth understanding of perfusion and allows targeting therapy to the pathophysiology rather than monitoring and targeting blood pressure. This change in approach is guided by the fact that perfusion disorders can result from a number of causes and a single management approach might do more harm than good. This approach has the potential to improve long term outcomes but needs to be tested in well-designed trials.

Medico-legal implications of the fetal inflammatory response syndrome.

Babies who sustain long term neurologic injury and disability are frequent subjects in medical malpractice litigation. In the United States, the tort system enables adjudication of claims through a proscribed system. This paper will review salient elements of the tort system-duty, breach, causation, and damages- and how they apply to encephalopathic infants whose injuries are believed to be the result of fetal inflammatory response syndrome (FIRS) and/or hypoxic-ischemic damage. FIRS may confound the diagnosis of neonatal encephalopathy but may be a credible explanation for it as well. The ways in which FIRS may impact malpractice lawsuits are presented.

Systematic Reviews in Neonatal Respiratory Care: Are Some Conclusions Misleading?

An increasing amount of information is currently available in neonatal respiratory care. Systematic reviews are an important tool for clinical decision-making. The challenge is to combine studies that address a specific clinical question and have similar characteristics in terms of populations, interventions, comparators, and outcomes, so that their combined results provide a more precise estimate of the effect that can be validly extrapolated into clinical practice. The concept of heterogeneity is reviewed, emphasizing that it should be considered in a wider perspective and not just as a mere statistical test. A case is made of how well-designed studies of the neonatal respiratory literature, when equivocally combined, can provide very precise but potentially biased results. Systematic reviews in this field and others should be rigorously peer-reviewed before publication to avoid misleading readers to potentially biased conclusions.

Persistent Respiratory Distress in the Term Neonate: Genetic Surfactant Deficiency Diseases.

Respiratory distress is one of the most common clinical presentations in newborns requiring admission to a Neonatal Intensive Care Unit (NICU). Many of these infants develop respiratory distress secondary to surfactant deficiency, which causes an interstitial lung disease that can occur in both preterm and term infants. Pulmonary surfactant is a protein and lipid mixture made by type II alveolar cells, which reduces alveolar surface tension and prevents atelectasis. The etiology of surfactant deficiency in preterm infants is pulmonary immaturity and inadequate production. Term infants may develop respiratory insufficiency secondary to inadequate surfactant, either from exposure to factors that delay surfactant synthesis (such as maternal diabetes) or from dysfunctional surfactant arising from a genetic mutation. The genetics of surfactant deficiencies are very complex. Some mutations are lethal in the neonatal period, while others cause a wide range of illness severity from infancy to adulthood. Genes that have been implicated in surfactant deficiency include SFTPA1, SFTPA2, SFTPB, SFTPC, and SFTPD (which encode for surfactant proteins A, B, C, and D, respectively); ABCA3 (crucial for surfactant packaging and secretion); and NKX2 (a transcription factor that regulates the expression of the surfactant proteins in lung tissue). This article discusses the interplay between the genotypes and phenotypes of newborns with surfactant deficiency to assist clinicians in determining which patients warrant a genetic evaluation.

Effect of Sustained Inflations vs Intermittent Positive Pressure Ventilation on Bronchopulmonary Dysplasia or Death Among Extremely Preterm Infants: The SAIL Randomized Clinical Trial.

Importance: Preterm infants must establish regular respirations at delivery. Sustained inflations may establish lung volume faster than short inflations. Objective: To determine whether a ventilation strategy including sustained inflations, compared with standard intermittent positive pressure ventilation, reduces bronchopulmonary dysplasia (BPD) or death at 36 weeks' postmenstrual age without harm in extremely preterm infants. Design, Setting, and Participants: Unmasked, randomized clinical trial (August 2014 to September 2017, with follow-up to February 15, 2018) conducted in 18 neonatal intensive care units in 9 countries. Preterm infants 23 to 26 weeks' gestational age requiring resuscitation with inadequate respiratory effort or bradycardia were enrolled. Planned enrollment was 600 infants. The trial was stopped after enrolling 426 infants, following a prespecified review of adverse outcomes. Interventions: The experimental intervention was up to 2 sustained inflations at maximal peak pressure of 25 cm H2O for 15 seconds using a T-piece and mask (n = 215); standard resuscitation was intermittent positive pressure ventilation (n = 211). Main Outcome and Measures: The primary outcome was the rate of BPD or death at 36 weeks' postmenstrual age. There were 27 prespecified secondary efficacy outcomes and 7 safety outcomes, including death at less than 48 hours. Results: Among 460 infants randomized (mean [SD] gestational age, 25.30 [0.97] weeks; 50.2% female), 426 infants (92.6%) completed the trial. In the sustained inflation group, 137 infants (63.7%) died or survived with BPD vs 125 infants (59.2%) in the standard resuscitation group (adjusted risk difference [aRD], 4.7% [95% CI, -3.8% to 13.1%]; P = .29). Death at less than 48 hours of age occurred in 16 infants (7.4%) in the sustained inflation group vs 3 infants (1.4%) in the standard resuscitation group (aRD, 5.6% [95% CI, 2.1% to 9.1%]; P = .002). Blinded adjudication detected an imbalance of rates of early death possibly attributable to resuscitation (sustained inflation: 11/16; standard resuscitation: 1/3). Of 27 secondary efficacy outcomes assessed by 36 weeks' postmenstrual age, 26 showed no significant difference between groups. Conclusions and Relevance: Among extremely preterm infants requiring resuscitation at birth, a ventilation strategy involving 2 sustained inflations, compared with standard intermittent positive pressure ventilation, did not reduce the risk of BPD or death at 36 weeks' postmenstrual age. These findings do not support the use of ventilation with sustained inflations among extremely preterm infants, although early termination of the trial limits definitive conclusions. Trial Registration: clinicaltrials.gov Identifier: NCT02139800.

Bronchopulmonary dysplasia: Myths of pharmacologic management.

Bronchopulmonary dysplasia (BPD) is the leading cause of long-term respiratory morbidity in newborns who require respiratory support at birth. BPD is a multifactorial disorder, and infants are frequently subjected to treatment with multiple pharmacologic agents of dubious efficacy and questionable safety, including diuretics, bronchodilators, corticosteroids, anti-reflux medications, and pulmonary vasodilators. These agents, with narrow therapeutic indices, are widely used despite the lack of an evidence base, and some may do more harm than good. It is incumbent on the clinician to establish a risk:benefit ratio and to avoid drugs that have little efficacy and a high rate of toxicity.

Administration of Inhaled Pulmonary Vasodilators to the Mechanically Ventilated Neonatal Patient.

Pulmonary hypertension is a life-threatening condition that affects people of all ages that can occur as an idiopathic disorder at birth or as part of a variety of cardiovascular and infectious disorders. It is commonly treated with inhaled pulmonary vasodilators such as nitric oxide and less frequently using formulations and analogs of prostacyclin. To minimize systemic effects and preserve pulmonary vasodilation, vasodilators are often administered directly into the airway. Nitric oxide is the only USA Food and Drug Administration-approved inhaled pulmonary vasodilator that can be used during mechanical ventilation. Over the past two decades, interest has grown in the use of aerosolized prostacyclin and prostacyclin analogs for the treatment of pulmonary hypertension during mechanical ventilation. Clinicians who administer inhaled prostacyclin may not have a clear understanding of its risks because of the lack of data from large clinical trials examining safety and efficacy; moreover, its safe use remains poorly documented. The off-label use of drugs is legitimate, but prescribers must recognize the potential complications and liability in doing so. This manuscript aims to address potential problems related to the aerosol administration of pulmonary vasodilators in the mechanically ventilated neonatal patient.

Pulmonary diagnostics.

Term infants with respiratory distress may have extremely varied etiologies of their illnesses. These range from anatomical malformations to infectious or inflammatory conditions to genetic, metabolic, or neurological abnormalities. This article reviews the present array of diagnostic studies available to the clinician, including the physical examination, imaging (radiography, computed tomography, magnetic resonance imaging, ultrasound, and nuclear scanning techniques), lung mechanics and function testing, evaluation of gas exchange (blood gases, pulse oximetry, transcutaneous monitoring, and end-tidal carbon monoxide measurements), and anatomical studies (bronchoscopy and lung biopsy). These tests and procedures are reviewed and a stepwise approach recommended.

Congenital chylothorax.

Congenital chylothorax (CC) results from multiple lymphatic vessel anomalies or thoracic cavity defects and may accompany other congenital anomalies. Fetal chylothorax may increase the risk of death and complications from pleural space lymphatic fluid accumulation, which compromises lung development, pulmonary, and cardiovascular function and from complications arising from the loss of drained lymphatic contents. Prenatal interventions might improve survival in severe cases of fetal chylothorax. The neonatal treatment strategy is generally supportive with interventions that include thoracostomy drainage and attempts to decrease chyle flow using a stepwise approach that begins with the least invasive means. Evidence-based treatment choices are lacking and are much needed. Most cases of CC resolve with time even without specific lymphatic system studies to identify the exact pathology. Expertise in performing lymphatic studies is not universally available. Data on both efficacy and safety of the various therapeutic options are needed to determine the best approach to the treatment of CC.

Basics of Infant Conventional Mechanical Ventilation: An Interactive Animated Teaching Module.

Introduction: While conventional mechanical ventilation is a common therapy in the neonatal intensive care unit (NICU), pediatric residents receive insufficient instruction. This stand-alone computer module provides an interactive method of learning basic infant pulmonary physiology and principles of mechanical ventilation. Methods: This module runs offline and is compatible with a variety of operating systems. Participants complete a six-question, case-based pretest. The seven-section instructional module is self-paced, narrated, animated, and interactive. Learners can repeat each section as needed. At the conclusion of the module, participants complete the same six-question test and receive feedback. In total, the module requires 15-20 minutes to complete. Results: The curriculum has been implemented at the beginning of the NICU rotation over a 2-year period within our pediatric residency program. Participants preferred this interactive module and had higher posttest scores when compared to a PowerPoint presentation. After 4 months, there was evidence of knowledge decay. Discussion: The interactive module is enjoyable, effective, and convenient. It engages participants in active learning and allows them to control the time and pace of their instruction. We have implemented the curriculum within our residency program and believe it would be useful for a variety of NICU health care providers.

Continuous Positive Airway Pressure: To Bubble or Not to Bubble?

Continuous positive airway pressure (CPAP) systems can be broadly grouped into continuous flow or variable flow devices. Bubble CPAP (bCPAP) is a continuous flow device and has physiologic properties that could facilitate gas exchange. Its efficacy has been reported to be similar to variable flow CPAP systems when used as a primary mode of respiratory support. Post-extubation bCPAP is reported to significantly reduce extubation failure rates among preterm infants ventilated for less than 2 week when compared to Infant flow driver CPAP (variable flow). bCPAP has been successfully used in resource-poor settings. The success on CPAP is however dependant on good nursing care and clear management protocols for weaning and escalation of care.