Respiratory failure in acutely ill infants and children may result from many different medical problems. In the neonate the most common causes are prematurity,respiratory distress syndrome asphyxia and aspiration pneumonia.under 2 years of age bronchopneumonia,broncochiolitis,status asthmaticus,croup,foreign body inhalation and congenital heart anomalies are more aetiologies.in children dren over 2 years asthma,central nervous system infection (eg. Meningitis)and trauma are more frequent.