<unk>  is a blockage of respiration in the<unk>  that hinders the free flow of air. It can be broadly classified into being either in the upper<unk>  (UPA) or lower<unk>  (LAO).<unk>  is a life-threatening condition and requires urgent attention, and assistance when it is needed. The assistance to clear an upper<unk>  would begin employing first-aid anti-choking techniques.
Airway obstruction
Mediastinal tumors
Pulmonary hyperplasia
Pulmonary aspiration
Hepatization of lungs
Pulmonary toxicity
Diaphragmatic spasm
Air trapping