The author found that in infants under two years of age the length of the trachea, that is, the distance between the front teeth and the bifurcation of the trachea, is usually 12 to 15 cm and the inside diameter is 6 to 7mm.
Accordingly bronchoscope of 20 cm. would be adequate for infants. An inside diameter of 5 mm or more is desirable for use of forceps. (An inside diameter of 3 mm might be available if only for inspection). The author had three different sized bronchoscopes manufactured for trial.
Their sizes are 25 cm long with 6 mm inside diameter, 25 cm long with 5 mm inside diamter and 20cm long with 4 mm inside diameter. These bronchoscopes have been found to be quite useful in older children as well as in infants.
These bronchoscopes are designed to connect with tubing for inhalation anesthesia and can be used as ventilating bronchoscopes.