The adult respiratory distress syndrome (ARDS) was described for the first time by Ashbaugh et al.(1) in 1967. Presently, ARDS is a well-known cause of acute respiratory failure in both adults and children after a variety of pulmonary or systemic insults including sepsis, shock, pneumonia, trauma, drug overdose, liquid aspiration, metabolic disorders, hematologic disorders, radiation pneumonitis, smoke inhalation, oxidant injury, and many others (2, 3). Regardless of the etiology of the lung injury, ARDS is characterized by five hallmarks:(a) severe arterial hypoxemia refractory to oxygen therapy,(b) increased intrapulmonary shunting,(c) decreased lung compliance,(d) decreased lung volumes, and (e) the absence of indicators of left ventricular failure ([pulmonary wedge pressure 4 8 mm Hg];[l-61). In adults, the incidence of ARDS in the United States is now estimated at 150,000 cases per year, and the associated mortality rate for full-blown ARDS has been reported at levels as high as 50%-70%(5). In the pediatric population, the incidence of ARDS has been reported at 8.5-10.4 cases per 1000 admissions to