The risk of a penetrating injury of the tracheobronchial wall is affected by a number of factors.
Demographic risk factors:
(1) age > 65 years
(2) female sex
Anatomic risk factors:
(1) congenital tracheal diverticulum
(2) tracheal distortion (from neoplasm or other cause)
(3) Mounier-Kuhn syndrome (tracheobronchomegaly)
(4) tracheal inflammation
(5) tracheal bronchus
Procedural risk factors for iatrogenic injury:
(1) inexperienced operator
(2) multiple/repeated attempts at intubation, especially if forceful (difficult intubation)
(3) use of a stylet during intubation
(4) incorrect tracheal tube size
(5) double-lumen tube
(6) poor postintubation care
(7) high balloon diameter during bronchoplasty