Laryngeal injury following endotracheal intubation: Have you considered reflux?

Laryngotracheal injury is an increasingly common complication of intubation and mechanical ventilation, with an estimated 87% of intubated and ventilated patients developing a laryngotracheal injury often preventing their rehabilitation from acute illness. Laryngotracheal injuries encompass a diverse set of pathologies including inflammation and oedema in addition to vocal cord ulceration and paralysis, granuloma, stenosis, and scarring. The existing literature has identified several factors including intubation duration, endotracheal tube size, type and cuff pressures, and technical factors including the skill and experience of the endoscopist. Despite these associations, a key aspect in the sequelae of laryngotracheal injuries is due to reflux and is not clearly related to iatrogenic and mechanical factors.Laryngopharyngeal reflux is a type of reflux that contaminates the upper aerodigestive tract. The combination of patient positioning and continuous nasogastric tube feeding act to affect the upper aerodigestive tract with acidic and non-acidic refluxate that causes direct and indirect mucosal injury impeding healing.Despite laryngopharyngeal reflux being an established and recognised causative factor of upper aerodigestive tract inflammatory pathology and laryngotracheal injury, it is very understudied in critical care. Further, there is yet to be an agreed pathway to assess, manage and prevent laryngotracheal injury in intubated and ventilated patients. The incidence of laryngopharyngeal reflux in the intubated and mechanically ventilated patient in the intensive care unit is currently unknown. Prospective studies may allow us to understand further potential mechanisms of upper aerodigestive tract injury due to laryngopharyngeal reflux and herald the development of preventative and management strategies of laryngopharyngeal reflux-mediated upper aerodigestive tract injury in critically ill patients.