<prompt> The narrowest pa of larynx in infants is at the cricoid level. In administering anesthesia this may lead to all except.Choosing a smaller size endotracheal tubeTrauma to the subglottic regionPost operative stridorLaryngeal oedema  <response>: A i.e. Choosing a smaller size endotracheal tubeEndotracheal tube that passes through the glottis may still impinge upon the cricoid cailage; the cricoid cailage is the narrowest point of the airway in children younger than 5 years of ageQMucosal trama can cause post operative edema, stridor, croup airway obstruction in subglottic glotic regionThe appropiate size of tube is estimated by an age based formula, which provides only a rough guide line however. Exceptions include premature neonates 2.5 to 3 mm tube and full term neonates 3-3.5 mm tubeCorrect tube size is confirmed by easy passage into the larynx and the development of gas leak at 15-20 cm H20 pressure. So the size of ETT depends on age, easy passage gasleak at 15-20 cm H20 pressure. 