Respiratory support of critically ill children

Abstract

Respiratory support for critically ill patients has been the cornerstone of intensive care medicine since the first report of the use of positive pressure ventilation during the polio epidemic of the 1950s. In the succeeding 30 years the principles that governed ventilator management were based on following the dictates of normal physiology. It was not until the introduction of high frequency ventilation in the 1970s that people began to question whether this was the best strategy in the injured lung. Added impetus has come from animal experiments demonstrating ventilator associated lung injury (VALI), which has resulted in the most fundamental process of reevaluation of mechanical ventilation practices seen since the therapy was introduced into clinical practice. Acute respiratory hypoxic failure (AHRF) in children can be broadly categorized into lung disease of neonates and infants, where it usually is a single system disease process involving only the lung, compared with older children where pulmonary failure is frequently part of a multiple system dysfunction syndrome and is in many ways similar to the adult with the acute respiratory distress syndrome (ARDS). In the former case, outcome may more closely related to the ventilation strategy or adjunctive therapies used to manage the pulmonary dysfunction while in the latter mortality is frequently related to the development of multiorgan failure. Consequently therapies that target the lung such as high frequency ventilation, surfactant and inhaled nitric oxide are more likely to make an impact in infants with AHRF compared to older children.