Postanaesthetic tracheal strictures in three rabbits

Within an 11-day period, three rabbits were anaesthetized for neutering. All were endotracheally intubated with 12 cm long, 2.5 mm (inner diameter [ID]) polyvinylchloride (PVC) tubes. All rabbits developed clinical signs of dyspnoea and upper respiratory tract obstruction, 17-21 days later. One rabbit was found dead; the other two were treated, but one was euthanized and one died. At necropsy examination, focal chronic inflammation and significant localized narrowing of the tracheal lumen was found in all cases. The affected sites corresponded to the position of the bevel of the endotracheal tube (ETT) during anaesthesia. Histopathology could not differentiate between a traumatic or chemical cause for the narrowing. Possible causes include trauma by the bevel of the ETT when turning the rabbit or preparing the surgical site or a chemical burn from incorrect disinfection or inadequate rinsing of the tubes. Iatrogenic tracheitis should be considered as a cause of dyspnoea, when clinical signs arise 2-3 weeks after anaesthesia.