Respiratory distress syndrome in the preterm neonate

As in the adult with acute lung injury and acute respiratory distress syndrome, the use of lung-protective ventilation has improved outcomes for neonatal lung diseases. Animal models of neonatal respiratory distress syndrome and congenital diaphragmatic hernia have provided evidence that ‘gentle ventilation’ with low tidal volumes and ‘open-lung’ strategies of using positive end-expiratory pressure or high-frequency oscillatory ventilation result in less lung injury than do the traditional modes of mechanical ventilation with high inflating pressures and volumes. Although findings of retrospective studies in infants with respiratory distress syndrome, congenital diaphragmatic hernia, and persistent pulmonary hypertension of the newborn have been similar to those of the animal studies, prospective, randomized, controlled trials have yielded conflicting results. Successful clinical trial design in these infants and in children with acute lung injury/acute respiratory distress syndrome will require an appreciation of the data supporting the modern ventilator management strategies for infants with lung disease. Introduction Although the first animal studies demonstrating the phenomenon of ventilator-induced lung injury (VILI) were published in the mid-1970s [1], it took 25 years to translate that information into a practice paradigm for treating adults with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) that is supported by a well designed, randomized, controlled clinical trial [2]. In the pediatric population, the smaller number of absolute cases of ALI/ARDS and lower mortality rate make it unlikely that a similar randomized, controlled clinical trial will be completed in the near future. For the moment, pediatric intensivists must extrapolate clinical trial results and ventilator algorithms from the adult population in their efforts to optimize outcomes in patients requiring mechanical ventilation. Fortunately, the practice of lung-protective ventilation is not at all revolutionary in neonatal and pediatric intensive care units, where protective modalities such as continuous positive airway pressure (CPAP), high-frequency oscillatory ventilation (HFOV), and extracorporeal membrane oxygenation (ECMO) have been widely utilized over the past 20 years. In the same way that ‘children are not just small adults’, as the saying goes, they are also not just ‘large babies’. Nevertheless, a thoughtful review of the evidence supporting current ventilator strategies used for neonatal respiratory distress syndrome (RDS), persistent pulmonary hypertension of the newborn (PPHN), and congenital diaphragmatic hernia (CDH) will help to guide the use of lung-protective strategies in the pediatric intensive care unit. Respiratory distress syndrome in the preterm neonate Nowhere is the potential harm caused by mechanical ventilation more evident than in the premature lung, which at birth is subject to the consequences of supplemental oxygen and mechanical ventilation. Although the ability to replace surfactant has reduced the severity of RDS and has permitted improved survival for even the most premature infants, the percentage of surviving infants who develop neonatal chronic lung disease (CLD) remains high [3,4]. As in adults with ARDS, the search for interventions that will improve outcomes in RDS has focused on determining the safest and most lung-protective means of providing mechanical ventilation to these infants. Review Bench-to-bedside review: Ventilator strategies to reduce lung injury – lessons from pediatric and neonatal intensive care Sally H Vitali1 and John H Arnold2 1Assistant, Department of Anesthesia and Critical Care Medicine, Children’s Hospital Boston, and Instructor in Anaesthesia, Harvard Medical School, Boston, Massachusetts, USA 2Senior Associate, Department of Anesthesia and Critical Care Medicine, Children’s Hospital Boston, and Associate Professor of Anaesthesia (Pediatrics), Harvard Medical School, Boston, Massachusetts, USA Corresponding author: John H Arnold, [email protected] Published online: 4 November 2004 Critical Care 2005, 9:177-183 (DOI 10.1186/cc2987) This article is online at http://ccforum.com/content/9/2/177 © 2004 BioMed Central Ltd