Pediatric research
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Congenital central hypoventilation syndrome (CCHS) patients exhibit respiratory deficits to ventilatory challenges, diminished breathing drive during sleep, and reduction of respiratory-related heart rate variation, but at least partially preserved peripheral chemoreception. We hypothesized that integration of afferent activity with respiratory motor output is deficient in CCHS, rather than chemoreceptor failure, and that examination of trends in heart and breathing rates and variabilities following ventilatory challenges may clarify the deficient mechanisms. Twelve children with CCHS and 12 age- and gender-matched control cases were subjected to hyperoxic hypercapnic, poikylocapnic hypoxic, and hyperoxic challenges while supine. ⋯ No heart rate variability group differences emerged in hypoxia, and only a late increase for CCHS cases developed in hyperoxia. The findings indicate retention of aspects of chemoreceptor sensitivity in CCHS cases. The heart rate alterations to ventilatory challenges suggest specific compensatory responses of a slower nature remain intact in CCHS, whereas other rapidly changing components are deficient.
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Estimating the risk of in-hospital mortality in the newborn intensive care unit can provide important information for health-care providers, and illness severity scores have been devised to provide mortality risk estimates. Calculation of illness severity scores is time-consuming, and the information used to predict mortality is collected only for the first 12 to 24 h of life. A noninvasive continuous measure that uses information collected throughout the hospitalization and that requires no data entry could be less costly and more informative. ⋯ The major findings were 1) the HRC index showed highly significant association with death in the succeeding 7 d (receiver-operating characteristic area > 0.7, p < 0.001), and 2) the cumulative HRC was highly significantly associated with neonatal in-hospital mortality (receiver-operating characteristic area > 0.80, p < 0.001). In both analyses, HRC added information to birth weight, gestational age, and postnatal age (p < 0.01). The HRC index provides independent information about the risk of neonatal death in the upcoming 7 d, and the cumulative HRC is an estimate of the risk of in-hospital neonatal mortality.
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Mechanical ventilation may interfere with the spontaneous breathing pattern in infants because they have strong reflexes that play a large role in the control of breathing. This study aimed to answer the following questions: does a ventilator-assisted breath 1) reduce neural inspiratory time, 2) reduce the amplitude of the diaphragm electrical activity, and 3) prolong neural expiration, within the delivered breath? In 14 infants recovering from acute respiratory failure (mean age and weight were 2.3 +/- 1.3 mo and 3.95 +/- 0.82 kg, respectively), we measured 1) the electrical activity of the diaphragm with a multiple-array esophageal electrode, and 2) airway opening pressure, while patients breathed on synchronized intermittent mandatory ventilation (mean rate, 11.2 +/- 6.5 breaths/min). We compared neural inspiratory and expiratory times for the mandatory breaths and for the spontaneous breaths immediately preceding and following the mandatory breath. ⋯ The magnitude of inspiratory electrical activity of the diaphragm was similar for all three breath conditions. For the mandatory breaths, ventilatory assist persisted for 507 +/- 169 ms after the end of neural inspiratory time. Infant-ventilator asynchrony (both inspiratory and expiratory asynchrony) was present in every mandatory breath and constituted 53.4 +/- 26.2% of the total breath duration.
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Historical Article
A short history of pediatric endocrinology in North America.
Pediatric endocrinology evolved as a subspecialty from the era of biochemical and metabolic clinical investigation led by John Howland, Edwards Park, and James Gamble at Johns Hopkins; Allan Butler at Boston University and Harvard University; Daniel Darrow at Yale University; and Irving McQuarrie at the University of Rochester and the University of Minnesota during the early 20th century. The father of the new subspecialty was Lawson Wilkins, a private pediatric practitioner in Baltimore, Maryland, who was invited by Dr. Edwards Park to establish an endocrine clinic at the Harriet Lane Home at Johns Hopkins in 1935. ⋯ The endocrinology sub-board of the American Board of Pediatrics was established in 1978 to certify training and competence in endocrinology, including diabetes. By 2002, the board had certified 927 pediatric endocrinologists. Pediatric endocrine subspecialists during the past half-century have contributed major advances in our understanding of the ontogeny of endocrine systems and the diagnosis and treatment of fetal-perinatal endocrine disorders; newborn screening for endocrine and metabolic disorders; the physiology and therapies for disorders of sexual differentiation and pubertal maturation; the development of anthropometric standards for childhood growth and development; the characterization and physiology of hormone systems, including receptors and hormone actions; the molecular genetics of a number of congenital endocrine disorders and heritable endocrine diseases; development of pediatric endocrine diagnostics and reference standards; the pathophysiology and management of autoimmune endocrine disease; and development of a growing armamentarium of therapeutic agents for treatment of endocrine and metabolic diseases.
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Historical Article
Development of pediatric pulmonology in the United Kingdom, Europe, and Australasia.
The organization of medicine in Europe, the UK and the Commonwealth countries was always much less formal than in the USA for many years and pediatricians interested in pediatric lung disease and asthma often started off as adult internists or specialists in adult pulmonary medicine. The early leaders in developing a special interest in the breathing of children during the 1940s and 1950s were predominantly physiologists and clinicians who began to apply physiological techniques to the study lung function in healthy and sick infants and children. ⋯ In fairly characteristic fashion, pulmonology in Europe was represented for a while by several different societies but due to the efforts of some dedicated enthusiasts there finally emerged the Paediatric Assembly of the European Respiratory Society (ERS) and its first Head, Max Zach, went to become President of the ERS itself. Despite some early doubts abut the future for pediatric pulmonology as a specialty in Europe and Australasia it is clearly flourishing as shown by the rising membership of the professional societies and the constant stream of high quality basic science and clinical publications.