Symptomatic tracheal stenosis in burns

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.

Inhibition of extracellular signal-regulated kinase pathway suppresses tracheal stenosis in a novel mouse model

Tracheal stenosis is a refractory and recurrent disease induced by excessive cell proliferation within the restricted tracheal space. We investigated the role of extracellular signal-regulated kinase (ERK), which mediates a broad range of intracellular signal transduction processes in tracheal stenosis and the therapeutic effect of the MEK inhibitor which is the upstream kinase of ERK. We histologically analyzed cauterized tracheas to evaluate stenosis using a tracheal stenosis mouse model. Using Western blot, we analyzed the phosphorylation rate of ERK1/2 after cauterization with or without MEK inhibitor. MEK inhibitor was intraperitoneally injected 30 min prior to cauterization (single treatment) or 30 min prior to and 24, 48, 72, and 96 hours after cauterization (daily treatment). We compared the stenosis of non-inhibitor treatment, single treatment, and daily treatment group. We successfully established a novel mouse model of tracheal stenosis. The cauterized trachea increased the rate of stenosis compared with the normal control trachea. The phosphorylation rate of ERK1 and ERK2 was significantly increased at 5 min after the cauterization compared with the normal controls. After 5 min, the rates decreased over time. The daily treatment group had suppressed stenosis compared with the non-inhibitor treatment group. p-ERK1/2 activation after cauterization could play an important role in the tracheal wound healing process. Consecutive inhibition of ERK phosphorylation is a potentially useful therapeutic strategy for tracheal stenosis.

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.

Laryngotracheal stenosis in burn patients requiring mechanical ventilation

Objective

To identify the incidence of laryngotracheal stenosis (LTS) in burn patients requiring mechanical ventilation at a regional academic burn center.

Methods

A retrospective review of all burn patients requiring endotracheal intubation or tracheostomy for airway management between 2003 and 2009 was performed. A group of trauma patients requiring similar airway instrumentation during the same period of time was used as a control.

Results

None of the trauma patients and 2 of the burn patients developed LTS. Both presented with stridor and were diagnosed within 2–5 weeks after extubation. One patient underwent successful carbon dioxide laser radial incision and dilation and continues to do well. The other patient failed endoscopic treatment and required T-tube placement. The incidence of LTS in burn patients requiring mechanical ventilation was 2.98% overall and 4.76% among those with inhalational injury.

Conclusions

Patients become symptomatic within weeks of the initial injury. Treatment is challenging and multiple surgical procedures are often required. A larger study is necessary to determine if the incidence is higher among burn patients.

Airway Reconstruction in Pediatric Burn Patients

OBJECTIVE: Reconstruction of the laryngotracheal airway in pediatric burn victims has been described anecdotally as less successful than reconstruction performed in other populations. To evaluate this clinical impression, outcomes of laryngotracheal reconstruction (LTR) in pediatric burn victims were compared with a randomly selected, matched control population of children receiving LTR.

DESIGN: Retrospective case control study.

SUBJECTS: The records of 34 pediatric burn victims undergoing LTR were reviewed. A control group of 48 children undergoing LTR for acquired stenosis was randomly selected from a population matched for age and grade of stenosis.

RESULTS: Decannulation rate after 1st procedure, number of open airway procedures required, and length of time after 1st procedure until decannulation were not significantly different between the 2 groups. Two deaths (both tracheostomy tube related) occurred in the burn group; 1 occurred in the control group. Two patients in the burn group and 3 patients in the control group remain tracheostomy tube dependent at least 1 year after the initial reconstructive attempt.

CONCLUSIONS: Long-term outcomes of LTR in burn patients are not significantly different from outcomes of LTR in the pediatric acquired airway stenosis population.

Diagnosis and management of inhalation injury: an updated review

In this article we review recent advances made in the pathophysiology, diagnosis, and treatment of inhalation injury. Historically, the diagnosis of inhalation injury has relied on nonspecific clinical exam findings and bronchoscopic evidence. The development of a grading system and the use of modalities such as chest computed tomography may allow for a more nuanced evaluation of inhalation injury and enhanced ability to prognosticate. Supportive respiratory care remains essential in managing inhalation injury. Adjuncts still lacking definitive evidence of efficacy include bronchodilators, mucolytic agents, inhaled anticoagulants, nonconventional ventilator modes, prone positioning, and extracorporeal membrane oxygenation. Recent research focusing on molecular mechanisms involved in inhalation injury has increased the number of potential therapies.

Treatment of tracheal stenosis with an extended tracheal cannula in a patient with extensive burn

Burn-induced tracheal stenosis is rare. This article reports an extensive burn patient who developed severe tracheomalacia and stenosis before wound healing. Given the ineffectiveness of the conventional techniques available for the treatment of tracheal stenosis, we used an extended tracheal cannula to dilate the narrowed part of the trachea successfully. As a result, the extensive burn wound was repaired, and the symptoms of tracheal stenosis were eventually relieved. No serious restenosis was observed during a 2-year follow-up period.

Airway management and smoke inhalation injury in the burn patient

Smoke inhalation injury, a unique form of acute lung injury, greatly increases the occurrence of postburn morbidity and mortality. In addition to early intubation for upper-airway protection, subsequent critical care of patients who have this injury should be directed at maintaining distal airway patency. High-frequency ventilation, inhaled heparin, and aggressive pulmonary toilet are among the therapies available. Even so, immunosuppression, intubation, and airway damage predispose these patients to pneumonia and other complications.

Tracheobronchial Stenosis Following Sulfur Mustard Inhalation

Sulfur mustard inhalation leads to different respiratory complications. In this article, we describe late stenotic effects of mustard gas inhalation on major airways. About 15 yr after exposure, suspect cases suffering from severe respiratory disorders underwent complete workup for central airway stenosis. Patients were evaluated with bronchoscopy and tracheal computerized tomography scan. The mean age of patients was 43+/-8 yr. The mean exposure time was 16+/-0.7 yr. The mean time between injury and diagnosis of tracheobronchial stenosis was 11.7+/-4.8 yr. Among the 33 referred cases with no other risk factor of stenosis, 8 cases had significant stenosis in their major airways, confirmed by tracheal computerized tomography scan and bronchoscopy. We conclude that direct toxic effects of sulfur mustard can lead to tracheobronchial stenosis with different degrees of involvement ranging from diffuse tracheal stenosis to stenosis of the isolated left main bronchus or glottic and subglottic stenosis.

Tracheal rupture in burns--a retrospective study

INTRODUCTION

Tracheal ruptures and tracheoesophageal injuries are rare, but life-threatening complications can arise during ventilation.

METHOD

A retrospective study of all burned patients placed on a ventilator between 2000 and 2005 (n=1693) identified two patients (0.1%) with a tracheal rupture and tracheoesophageal fistula (TOF). The diagnoses were confirmed using endoscopy and computed tomography. The tracheal and oesophageal defects were treated surgically immediately after diagnosis using a collar approach.

RESULTS

In all cases, withdrawal of ventilation proceeded without problems. Depending on their underlying condition, patients were transferred to normal wards with adequate spontaneous breathing and oral feeding.

CONCLUSION

Tracheal rupture and tracheoesophageal injury following orotracheal intubation is a rare complication in patients with burns (0.1% incidence). Following diagnosis, immediate surgical intervention is effective without further complications.

Lésions respiratoires et brûlures

INTRODUCTION

Smoke inhalation and respiratory complications are still the major causes of mortality in severely burned patients.

STATE OF THE ART

The diagnosis is suspected clinically on the basis of history and physical examination and can be confirmed bronchoscopically. Respiratory failure in burned patients occurs through a number of associated mechanisms. Pneumonitis and adult respiratory distress syndrome (ARDS) are common early complications. New pulmonary treatments and advances in ventilation have reduced the incidence of both barotrauma and infectious complications. Tracheal stenosis can occur as a late complication of prolonged mechanical ventilation.

PERSPECTIVES

Clinical and experimental studies have shown that damage to the mucosal barrier and the release of inflammatory mediators are the most important pathophysiological events following smoke inhalation. Manipulation of the inflammatory response following inhalation may be a treatment option in the distant future.

CONCLUSION

Inhalation injury occurring in burned patients can produce severe respiratory and systemic complications.

Inhalation injury in the burn patient

Patients who survive to hospital admission after bums with inhalation injury face a difficult and potentially prolonged course of treatment in the burn center. Continuing survival and especially functional outcome hinges on the patient's receiving comprehensive, well-coordinated care from an interdisciplinary team of skilled health care providers. The best care plan combines close monitoring of vital organ/tissue perfusion indicators, aggressive management of pulmonary compromise, and scrupulous attention to all details of nursing care. Many patients suffer complications from their injuries or treatment, and not all survive. Those who do may face prolonged and painful therapies on the way to recovery. The expert nurse managing and caring for this unfortunate population faces tremendous clinical challenges but also has the opportunity and satisfaction of helping each patient achieve the best possible outcome.

Duration of dysphagic symptoms and swallowing outcomes after thermal burn injury

Levels of swallowing disability, patterns of dysphagia rehabilitation and swallowing outcomes on discharge were retrospectively reviewed for 30 patients with thermal burn injury (with or without inhalation injury), referred to speech pathology services for dysphagia management. The average total surface burn area of the group was 50%. All patients were mechanically ventilated for an average of 24 days, with 80% of patients requiring subsequent tracheostomy. Initial dysphagia assessment occurred approximately 20 days after admission, whereas first safe oral intake was achieved by approximately 30 days. Supplementary nutrition and hydration was necessary for all patients. The time to achieve oral intake without supplementation was 53 days. Outcome measures revealed a significant improvement in swallowing function throughout the duration of inpatient stay, with 90% of patients discharged safely tolerating a normal diet, 6.7% of patients managing soft diet consistencies, and 3.3% managing soft puree consistencies on discharge.

Effects of tracheostomies on infection and airway complications in pediatric burn patients

Considerable controversy exists as to whether tracheostomy is ever indicated in burn patients. New advents in the treatment of inhalation injury have improved survival, making the use of tracheostomy more usual. The purpose of this study was to analyze the outcome of tracheostomies, and the effect of time on complications. Patients requiring ventilatory support and tracheostomies were studied. Demographic data, hospital course, ventilatory parameters and complications were analyzed. Two hundred ninety patients required ventilation and 36 tracheostomy. Mean percentage of TBSA burned was 59%+/-4. Ninety percent of these patients presented with inhalation injury. Mortality in tracheostomy patients was 25 and 16% in all ventilated patients. Thirty-five percent of the patients developed late complications. Patients who had their airway converted to tracheostomy before day 10 postinjury had a significantly lower incidence of subglottic stenosis. and patients who required airway pressures over 50 cm H2O for more than 10 days had a significantly higher incidence of tracheomalacia. Pneumonia occurred at similar incidence in ventilated and tracheostomy patients. The mortality and late complications of pediatric burn patients with tracheostomy has decreased over the last decade. They do not present with higher incidence of pneumonia. Maintenance of airway pressures below 50 cm H2O and conversion of the artificial airway to tracheostomy before day 10 postinjury may be advisable in patients requiring long term ventilation to prevent late complications.