ASA	American Society of Anesthesiologists
CT	computed tomography
FDA	Food and Drug Administration
FEV1	forced expiratory volume in one second
FVC	forced vital capacity
IQR	interquartile range
PITS	post-intubation tracheal stenosis
POTS	post-operative tracheal stenosis
PTBS	post-tuberculous tracheobronchial stenosis
PTTS	post-tracheostomy tracheal stenosis
SEMS	self-expandable metallic stents
TBS	tracheobronchial stenosis