 Of 4 @,@ 460 claims in the American Society of <unk> ( ASA ) Closed Claims Project database , 266 ( approximately 6 % ) were for airway injury . Of these 266 cases , 87 % of the injuries were temporary , 5 % were permanent or disabling , and 8 % resulted in death . Difficult intubation , age older than 60 years , and female gender were associated with claims for perforation of the esophagus or pharynx . Early signs of perforation were present in only 51 % of perforation claims , whereas late sequelae occurred in 65 % . 
