Laryngotracheal stenosis in burn patients requiring mechanical ventilation

Inhalation Injury, Respiratory Failure, and Ventilator Support in Acute Burn Care

Sustaining an inhalation injury increases the risk of severe complications and mortality. Current evidential support to guide treatment of the injury or subsequent complications is lacking, as studies either exclude inhalation injury or design limit inferences that can be made. Conventional ventilator modes are most commonly used, but there is no consensus on optimal strategies. Settings should be customized to patient tolerance and response. Data for pharmacotherapy adjunctive treatments are limited.

Long-Term Laryngotracheal Complications After Inhalation Injury: A Scoping Review

Long-term laryngotracheal complications (LTLC) after inhalation injury (II) are an under-recognized condition in patients with burns. The purpose of this study was to systematically review all available evidence on LTLC after II and identify gaps in knowledge to guide the direction of future research. A scoping review was performed to synthesize all available evidence on LTLC after II, as guided by the question, "What are the LTLC after II, in patients with or without a history of translaryngeal intubation and/or tracheostomy?". MEDLINE, Web of Science, Ovid Embase, Cochrane Library, and Google Scholar were searched for publications on this topic. Of the 3567 citations screened, a total of 153 full-text articles were assessed for eligibility and 49 were included in the scoping review. The overall level of evidence was low, with case reports constituting 46.7% of all included human studies. The lesions were most frequently in the trachea (36.9%), followed by the glottis (34.7%) and subglottis (19.0%). LTLC occur in 4.8 to 6.5% of patients after II and these complications are under-recognized in burns patients. The risk factors for LTLC include high-grade II, elevated initial inflammatory responses, prolonged translaryngeal intubation, and a history of tracheostomy. The goal of management is to restore airway patency, preserve voice quality, and restore normal diet and swallow function. There is limited high-level evidence on LTLC, particularly with regards to long-term functional morbidity in voice and swallow. Large, prospective studies are required to address this gap in knowledge.

Laryngotracheal stenosis post mechanical ventilation in paediatric burns patients

INTRODUCTION

The duration of endotracheal intubation is thought to be the most important factor in the development of acquired laryngotracheal stenosis (LTS); however, there is a paucity of studies examining the incidence of LTS in the paediatric burn population. The aim of this study was to determine the incidence of LTS in paediatric burns patients requiring mechanical ventilation to develop guidelines for consideration of a tracheostomy.

METHODS

A retrospective review of all children treated at The Children's Hospital at Westmead (CHW) Burns Unit (BU) from December 2009 to December 2019 who required intubation for their burn injury.

RESULTS

During the 10-year study period 115 patients required endotracheal intubation after having sustained a burn injury. Of these 11 were excluded. The mean age was 6.2 years (0-16), with the majority of patients being male (65%). The average TBSA was 18.5% with a range of 0.1-70%. Flame was the most common mechanism of burn (n = 59). Burns to the head and/or neck were the most common indication for intubation with the mean duration of intubation 6.1 days (range 0-40). Tracheostomies were performed on two patients (1.9%). LTS was found in two patients (1.9%).

CONCLUSION

LTS in the paediatric burn population post mechanical ventilation appears to be a rare event. Endotracheal intubation can safely be used as the route of airway access in paediatric burns patients. Based on our experience, a definitive recommendation on the timing of tracheostomy in the paediatric burn patient cannot be made.

Laryngeal inhalational injuries: A systematic review

Laryngeal inhalation injury carries a significant increase in mortality rate and often indicates immediate airway evaluation. This may be difficult in the setting of clinical deterioration necessitating immediate intubation, which itself can synergistically cause mucosal damage. Prior studies do not encompass predictive factors or long-term outcomes for the laryngotracheal complex. This systemic review of PubMed, Embase, and Cochrane identified studies investigating inhalational injuries of the upper airway. Demographic data as well as presentation, physical findings, and delayed sequelae were documented. Laryngotracheal burn patients were divided into two cohorts based on timing of laryngeal injury diagnosis (before- versus after-airway intervention). 1051 papers met initial search criteria and 43 studies were ultimately included. Airway stenosis was more common in patients that were intubated immediately (50.0%, n = 18 versus 5.2%, n = 13; p = 0.57). Posterior glottic involvement was only identified in patients intubated prior to airway evaluation (71.4%, n = 15). All studies reported a closed space setting for those patients in whom airway intervention preceded laryngeal evaluation. Laryngeal inhalational injuries are a distinct subset that can have a variety of minor to severe laryngotracheal delayed sequelae, particularly for thermal injuries occurring within enclosed spaces. Given these findings, early otolaryngology referral may mitigate or treat these effects.