In 1922, Myerson1 studied the tracheobronchial tree and its contents immediately after tonsillectomy under general anesthesia in a series of one hundred cases. When the bleeding was entirely controlled and the pharynx was dry, a direct laryngoscopy and tracheobronchoscopy was performed. In all but three cases the operation was performed with the patient's head placed on the end of a table which was dropped to an angle of 45 degrees. Suction was used in all cases. In his series of one hundred cases, he found that seventy-nine patients has aspirated blood and pharyngeal contents in varying amounts into the tracheobronchial tree, and one patient who showed blood in the trachae and each bronchus at operation died six days later of bronchopneumonia.
In 1924, Myerson2 repeated the examination in another series of one hundred cases. In this series, he was investigating chiefly whether cough did protect the tracheobronchial tree