Blaming the balloon: the risk of post-intubation tracheobronchial rupture

Abstract

The pre-hospital retrieval service attended the home of an 82-year-old, 68 kg woman found unconscious with no evidence of trauma. Her airway was obstructed by vomit, oxygen saturation was 48 % and Glasgow Coma Score was six. The pupils were small and reactive. A cerebrovascular accident was presumed. The airway was suctioned, followed by rapid sequence induction with etomidate and succinylcholine. Intubation was performed with a size 7 Mallinckrodt endotracheal tube (ETT) (Mallinckrodt HiContour Oral Tracheal Tube Cuffed, Covidien llc, 15 Hampshire Street, Mansfield, MA 02048) containing a preformed stylet, which was removed once the ETT passed through the vocal cords. Post-intubation auscultation was symmetric, oxygen saturation rose to 95 %, and the ETT position was confirmed by capnography. No further drugs were administered for transfer while the hemodynamic profile was uneventful. A CT brain scan was normal, while a cervico-thoracic CT scan revealed mediastinal emphysema predominant in the left para-tracheal region, subcutaneous emphysema of the neck and a sub-glottic ETT cuff measuring 3 cm in diameter. No pneumothorax was present. Lesions of the trachea or oesophagus were not demonstrated. Changes in the lung fields were suggestive of bronchoaspiration, and the patient subsequently developed acute respiratory distress syndrome. The initial chest radiograph is shown in Fig. 1. While intubation had been uneventful, the patient was observed to cough vigorously on the ETT in the emergency department (ED), but administration of further sedation or neuromuscular blocking agent was withheld to allow subsequent neurological assessment. At this time, the Ambu bag circuit in use had no expiratory valve. Bronchoscopy showed an ETT tip 4 cm above the carina, food debris and purulent secretions at the carina and throughout the tracheobronchial tree. There was a 4 cm vertical tear of the posterior wall of the membranous trachea between the first and fifth tracheal rings. The ETT cuff was repositioned distal to the lesion. Surgical repair was not performed. Spontaneous tracheal healing on day 23 was confirmed by bronchoscopy, but the patient redeveloped pneumonia with no neurological improvement. An MRI imaging of the brain showed diffuse leucoencephalopathy, thought to be from hypoxia secondary to bronchoaspiration, on a background of dysphagia. After discussion with the family, treatment limits were agreed, and the patient subsequently died on day 40. J. R. Reilly Emergency Department and Anaesthesia Department, Lausanne University Hospital, Lausanne, Switzerland