Auscultation is appropriate to ascertain these properties as well as those enumerated previously. Again one does not need to commit to memory a long list of specific etiologies of airway obstruction in neonates as long as one understands the process by which a differential diagnosis can be developed. I t is useful to evaluate the different regions of the airway in regards to the characteristic features which may be present when airway obstruction exists. This is accomplished best when one proceeds in a logical manner, sequentially evaluating voice, stridor, retractions, ability to feed, position of the mouth and the presence or absence of cough. I n children with nasal obstruction the voice is generally normal but may be hyponasal when obstruction exists.
True stridor is absent but stertor does exist when there is significant narrowing.
The child generally feeds well and has no retractions unless the airway obstruction is severe. Mouth breathing is obligatory and cough generally is absent. I n contrast, children with oropharyngeal obstruction present in a very different manner. The voice is usually unaffected but it may be full. The child usually has course inspiratory stridor associated with sternal and intracostal retractions early and total chest retractions with increased obstruction.