Neonatology
-
Chronic respiratory morbidity is a common adverse outcome of preterm birth, especially in infants who develop bronchopulmonary dysplasia (BPD), which is still a major cause of long-term lung dysfunction with a heavy burden on health care services and medical resources throughout childhood. The most severely affected patients remain symptomatic even in adulthood, and this may be influenced also by environmental variables (e.g. smoking), which can contribute to persistent obstruction of airflow. ⋯ Since the prevention of BPD is an elusive goal, minimizing neonatal lung injury and closely monitoring survivors remain the best courses of action. This review describes the clinical and functional changes characteristic of the long-term pulmonary sequelae of preterm birth, focusing particularly on BPD.
-
Caffeine, a methylxanthine and nonspecific inhibitor of adenosine receptors, is an example of a drug that has been in use for more than 40 years. It is one of the most commonly prescribed drugs in neonatal medicine. However, until 2006, it had only a few relatively small and short-term studies supporting its use. ⋯ The most frequent indication for therapy reported in CAP was treatment of documented apnea, followed by the facilitation of the removal of an endotracheal tube. Only about 20% of the neonatologists in the trial started caffeine for the prevention of apnea and the findings of CAP cannot automatically be extrapolated to an exclusive prophylactic indication. However, recent data suggest that the administration of prophylactic methylxanthine by neonatologists is now common practice.
-
Review Comparative Study
Elective high-frequency oscillatory ventilation versus conventional ventilation for acute pulmonary dysfunction in preterm infants.
Respiratory failure due to lung immaturity is a major cause of mortality in preterm infants. Although the use of intermittent positive pressure ventilation in neonates with respiratory failure saves lives, its use is associated with lung injury and chronic lung disease (CLD). A newer form of ventilation called high-frequency oscillatory ventilation (HFOV) has been shown to result in less lung injury in experimental studies. ⋯ Seventeen eligible studies of 3,652 infants were included. Meta-analysis comparing HFOV with CV revealed no evidence of effect on mortality at 28-30 days of age or at approximately term equivalent age. These results were consistent across studies and in subgroup analyses. The effect of HFOV on CLD in survivors at term equivalent gestational age was inconsistent across studies and the reduction was of borderline significance overall. The effect was similar in trials with a high lung volume strategy for HFOV targeting at very low FiO(2) and trials with a high lung volume strategy with somewhat higher or unspecified target FiO(2). Subgroups of trials showed a significant reduction in CLD with HFOV when no surfactant was used, when piston oscillators were used for HFOV, when lung protective strategies for CV were not used, when randomization occurred at two to six hours of age, and when inspiratory:expiratory ratio of 1:2 was used for HFOV. In the meta-analysis of all trials, pulmonary air leaks occurred more frequently in the HFOV group. In some studies, short-term neurological morbidity with HFOV was found, but this effect was not statistically significant overall. The subgroup of two trials not using a high-volume strategy with HFOV found increased rates of grade 3 or 4 intraventricular hemorrhage and of periventricular leukomalacia. An adverse effect of HFOV on long-term neurodevelopment was found in one large trial but not in the five other trials that reported this outcome. The rate of retinopathy of prematurity is reduced overall in the HFOV group.
-
Review Historical Article
The journey towards lung protective respiratory support in preterm neonates.
The aim of this conceptual review is to provide the reader with a broad perspective on progress made in respiratory support of preterm infants over the past five decades. Landmark discoveries are described in their historical context and underlying theories of lung protection are discussed. The review finishes by integrating different approaches and perspectives into a state-of-the-art concept for lung-protective ventilation in this fragile patient population. ⋯ Given the fact that progress made in the last decade has only resulted in minor improvements in mortality and morbidity rates of neonates with respiratory failure, it seems unlikely that further refinements of current technologies will produce giant leaps forward in high-resource countries. It appears that entirely new approaches would be required. In contrast, knowledge and technology transfer of basic respiratory support strategies (e.g. use of oxygen, simple systems to provide continuous positive airway pressure), could have an enormous impact on the prognosis of neonates with respiratory failure in low-resource countries.
-
Hemodynamic problems are common in neonatal intensive care. They occur in the context of incomplete myocardial and vascular development and in cardiovascular responses to interventions which are, as a result, limited and often uncertain and unpredictable. In this review, I outline the hemodynamic features of 4 neonatal conditions which often require intervention: (1) persistent pulmonary hypertension of the newborn, (2) cardiogenic shock (most commonly in the context of hypoxic ischemic injury), (3) sepsis and (4) low blood pressure in the transitional period of the extremely preterm infant. I also look at the evidence which exists for effective interventions and the most important research questions for the future.