Fixed airway obstruction refers to a condition in which the airways are partially or completely blocked. This blockage is permanent or "fixed", meaning that it does not improve over time or with treatment. The obstruction makes breathing difficult, which can cause symptoms such as shortness of breath, difficulty breathing, coughing, and a feeling of tightness in the chest. The obstruction can occur in various places in the airways, including the nose, throat, trachea, and bronchi. Fixed airway obstruction can be the result of various diseases.