Isolated smoke inhalation injuries: Acute respiratory dysfunction, clinical outcomes, and short-term evolution of pulmonary functions with the effects of steroids

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.

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.

An update on the role of bronchoscopy in the diagnosis of pulmonary disease

Bronchoscopy has evolved over the past few decades and has been used by respiratory physicians to diagnose various airway and lung diseases. With the popularization of medical check-ups and growing interest in health, early diagnosis of lung diseases is essential. With the development of endobronchial ultrasound, ultrathin bronchoscopy, and electromagnetic navigational bronchoscopy, bronchoscopy has been able to widen its scope in diagnosing pulmonary diseases. In this review, we have described the brief history, role, and complications of bronchoscopy used in diagnosing pulmonary lesions, from simple flexible bronchoscopy to bronchoscopy combined with several up-to-date technologies.

Pharmacological treatment of inhalation injury after nuclear or radiological incidents: The Chinese and German approach

Inhalation injury is often associated with burns and significantly increases morbidity and mortality. The main toxic components of fire smoke are carbon monoxide, hydrogen cyanide, and irritants. In the case of an incident at a nuclear power plant or recycling facility associated with fire, smoke may also contain radioactive material. Medical treatments may vary in different countries, and in this paper, we discuss the similarities and differences in the treatments between China and Germany. Carbon monoxide poisoning is treated by 100% oxygen administration and, if available, hyperbaric oxygenation in China as well as in Germany. In addition, antidotes binding the cyanide ions and relieving the respiratory chain are important. Methemoglobin-forming agents (e.g., nitrites, dimethylaminophenol) or hydroxocobalamin (Vitamin B12) are options. The metabolic elimination of cyanide may be enhanced by sodium thiosulfate. In China, sodium nitrite with sodium thiosulfate is the most common combination. The use of dimethylaminophenol instead of sodium nitrite is typical for Germany, and hydroxocobalamin is considered the antidote of choice if available in cases of cyanide intoxications by fire smoke inhalation as it does not further reduce oxygen transport capacity. Systematic prophylactic use of corticosteroids to prevent toxic pulmonary edema is not recommended in China or Germany. Stable iodine is indicated in the case of radioiodine exposure and must be administered within several hours to be effective. The decorporation of metal radionuclides is possible with Ca (DTPA) or Prussian blue that should be given as soon as possible. These medications are used in both countries, but it seems that Ca (DTPA) is administered at lower dosages in China. Although the details of the treatment of inhalation injury and radionuclide(s) decorporation may vary, the general therapeutic strategy is very similar in China and Germany.

Acute clinical manifestations in toxic smoke inhalation victims: systematic review of observational studies

Abstract Introduction: Lung injuries from toxic smoke inhalation are the main causes of death in fire victims; however, information regarding the acute effects on the respiratory system after smoke inhalation and its constituents in closed environments are still scarce in literature. Objective: To investigate the acute clinical manifestations observed in victims of smoke inhalation during enclosed-space fires by means of systematic review. Methods: A systematic search was conducted in the following databases: MEDLINE (via PubMed), Lilacs, Scopus and Web of Science. There were no appliedrestrictions in terms of thepublication date. In addition, a manual search was performed on the references of published studies. Observational studies assessing the prevalence of acute clinical manifestations in victims of toxic smoke inhalation in closed environments were included. Results: Of the 4,603 articles identified, eight were included, comprising a total of 233 patients. The signs and symptoms were identified and ranked according to frequency. Dyspnea (58.80%, six studies), carbonaceous sputum (54.51%, four studies), hoarseness (39.91%, three studies), wheezing (34.33%, five studies) and sore throat (33.90%, two studies) were the most frequent acute clinical manifestations of smoke inhalation. Besides these, chest pain and pulmonary edema were observed, respectively in 13.30%, 5.15% of the studies. Conclusion: The results suggest that dyspnea, carbonaceous sputum, hoarseness, wheezing and sore throat were the most frequent acute clinical manifestations in victims of smoke inhalation. Further studies of a higher level of evidence and greater methodological rigor are required.

Smoke Inhalation Injury: Etiopathogenesis, Diagnosis, and Management

Smoke inhalation injury is a major determinant of morbidity and mortality in fire victims. It is a complex multifaceted injury affecting initially the airway; however, in short time, it can become a complex life-threatening systemic disease affecting every organ in the body. In this review, we provide a summary of the underlying pathophysiology of organ dysfunction and provide an up-to-date survey of the various critical care modalities that have been found beneficial in caring for these patients. Major pathophysiological change is development of edema in the respiratory tract. The tracheobronchial tree is injured by steam and toxic chemicals, leading to bronchoconstriction. Lung parenchyma is damaged by the release of proteolytic elastases, leading to release of inflammatory mediators, increase in transvascular flux of fluids, and development of pulmonary edema and atelectasis. Decreased levels of surfactant and immunomodulators such as interleukins and tumor-necrosis-factor-α accentuate the injury. A primary survey is conducted at the site of fire, to ensure adequate airway, breathing, and circulation. A good intravenous access is obtained for the administration of resuscitation fluids. Early intubation, preferably with fiberoptic bronchoscope, is prudent before development of airway edema. Bronchial hygiene is maintained, which involves therapeutic coughing, chest physiotherapy, deep breathing exercises, and early ambulation. Pharmacological agents such as beta-2 agonists, racemic epinephrine, N-acetyl cysteine, and aerosolized heparin are used for improving oxygenation of lungs. Newer agents being tested are perfluorohexane, porcine pulmonary surfactant, and ClearMate. Early diagnosis and treatment of smoke inhalation injury are the keys for better outcome.

Bronchial wheezing predicts inflammation and respiratory failure in fire smoke victims

BACKGROUND

Acute fire smoke inhalation injury involves inflammatory mediators whose roles are poorly understood. We carried out a prospective observational study of fire smoke victims to identify clinical and biochemical markers that may predict pulmonary dysfunction and investigated possible correlations between dysfunction and cytokines in bronchoalveolar lavage (BAL) fluid and blood.

METHODS

Forty patients with respiratory and/or neurological symptoms following acute fire smoke inhalation had pulmonary function tests and blood gas analyses performed on admission, at discharge, and after 3 months. Cytokines were measured using BioPlex/XMap technology.

RESULTS

On admission, 30 (75%) patients had dyspnea. Patients presenting with bronchial wheezing (n = 14) had significantly lower PEF (201 l/min, 82-360) than non-wheezing patients (406 l/min, 100-683) (n = 16, P = 0.03). Bronchial wheezing predicted need for ICU treatment with OR = 93.3 at 95% CI (P < 0.001) and was associated with gas exchange impairment, with mean p_a O₂ /FiO₂ ratio 34.4 (11.8-49.8) kPa on admission and 21.3 (8.3-44.5) kPa 48 h later. Blood HbCO also predicted ICU treatment, with OR = 1.58 at 95% CI (P < 0.001). Serum CRP, IL-6, IL-8, and MCP-1 were significantly higher in wheezing patients after 12-24 h compared with non-wheezing patients and study controls. Cytokine levels were still elevated after 3 months. BAL fluid had significantly higher levels of IL-8, MCP-1, IL-1β, and G-CSF compared with healthy controls.

CONCLUSION

In victims of fire smoke inhalation, pulmonary wheezing predicts inflammation, pulmonary dysfunction, respiratory failure, and need for intensive care.

Extensive Causative Esophagitis Caused by Thermal Injury: A Case Report and Review of the Literature

Esophagus thermal injury is a rare case that can be easily overlooked by practitioners. We herein present a case of thermally induced diffuse corrosive esophagitis with complaints of dysphagia and retrosternal chest pain after having steamed pork. A thorough disease course was demonstrated by serials of endoscopy images and video. A comprehensive review of articles and a concise overview of esophageal thermal injury clinical manifestation, disease process, typical endoscopy features, pharmacomanagement option, and outcomes will be conducted in this article.

Smoke inhalation increases intensive care requirements and morbidity in paediatric burns

Burn survival has improved with advancements in fluid resuscitation, surgical wound management, wound dressings, access to antibiotics and nutritional support for burn patients. Despite these advancements, the presence of smoke inhalation injury in addition to a cutaneous burn still significantly increases morbidity and mortality. The pathophysiology of smoke inhalation has been well studied in animal models. Translation of this knowledge into effectiveness of clinical management and correlation with patient outcomes including the paediatric population, is still limited. We retrospectively reviewed our experience of 13 years of paediatric burns admitted to a regional burn's intensive care unit. We compared critical care requirements and patient outcomes between those with cutaneous burns only and those with concurrent smoke inhalation injury. Smoke inhalation increases critical care requirements and mortality in the paediatric burn population. Therefore, early critical care input in the management of these patients is advised.

The wound/burn guidelines - 6: Guidelines for the management of burns

Burns are a common type of skin injury encountered at all levels of medical facilities from private clinics to core hospitals. Minor burns heal by topical treatment alone, but moderate to severe burns require systemic management, and skin grafting is often necessary also for topical treatment. Inappropriate initial treatment or delay of initial treatment may exert adverse effects on the subsequent treatment and course. Therefore, accurate evaluation of the severity and initiation of appropriate treatment are necessary. The Guidelines for the Management of Burn Injuries were issued in March 2009 from the Japanese Society for Burn Injuries as guidelines concerning burns, but they were focused on the treatment for extensive and severe burns in the acute period. Therefore, we prepared guidelines intended to support the appropriate diagnosis and initial treatment for patients with burns that are commonly encountered including minor as well as moderate and severe cases. Because of this intention of the present guidelines, there is no recommendation of individual surgical procedures.

Smoke inhalation injury during enclosed-space fires: an update

In view of the tragic fire at a nightclub in the city of Santa Maria, Brazil, which culminated in the sudden death of 232 young people, we decided to review the literature regarding smoke inhalation injury caused by enclosed-space fires, which can be divided into direct thermal damage, carbon monoxide poisoning, and cyanide poisoning. Such injuries often call for immediate orotracheal intubation, either due to acute airway obstruction or due to a reduced level of consciousness. The diagnosis and the severity of the thermal injury can be determined by fiberoptic bronchoscopy. The levels of gases and gas by-products in the bloodstream should be assessed as rapidly as possible, even while still at the scene of the incident. First responders can also treat carbon monoxide poisoning, with immediate administration of oxygen at 100%, as well as cyanide poisoning, with oxygen therapy and hydroxocobalamin injection.

Application of flexible bronchoscopy in inhalation lung injury

Background

As acute inhalational injury is an uncommon presentation to most institutions, a standard approach to its assessment and management, especially using flexible bronchoscopy, has not received significant attention.

Methods

The objective of this study is to evaluate the value of using flexible bronchoscopy as part of the evaluation and management of patients with inhalational lung injury. Twenty-three cases of inhalational lung injury were treated in our three hospitals after a fire in a residential building. The twenty cases that underwent bronchoscopy as part of their management are included in this analysis. After admission, the first bronchoscopy was conducted within 18-72 hours post inhalational injury. G2-level patients were reexamined 24 hours after the first bronchoscopy, while G1-level patients were reexamined 72 hours later. Subsequently, all patients were re-examined every 2-3 days until recovered or until only tunica mucosa bronchi congestion was identified by bronchoscopy.

Results

Twenty patients had airway injury diagnosed by bronchoscopy including burns to the larynx and glottis or large airways. Bronchoscopic classification of the inhalation injury was performed, identifying 12 cases of grade G1 changes and 8 cases of grade G2. The airway injury in the 12 cases of grade G1 patients demonstrated recovery in 2-8 days, in the airway injury of the 8 cases of grade G2 patients had a prolonged recovery with airway injury improving in 6-21 days averaged. The difference in recovery time between the two groups was significant (P <0.05).

Conclusions

The use of flexible bronchoscopy has great value in the diagnosis of inhalational injury without any complications. Its use should be incorporated into clinical practice.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1476676925108926

Early single-shot intravenous steroids do not affect pulmonary complications and mortality in burned or scalded patients

BACKGROUND AND OBJECTIVES

Inhalation injury, especially in combination with cutaneous burns, is the major cause of morbidity and mortality in patients admitted to burn care centers. Either with or without the presence of a cutaneous burn, inhalation injury contributes to high risk for developing severe pulmonary complications. Steroids may reduce a prolonged and destructive inflammatory response to toxic or allergic substances. The objective of this study was to evaluate the effect of early single-shot intravenous steroids on pulmonary complications and mortality in burned or scalded patients with or without inhalation injury.

METHODS

Retrospective analysis of a prospective single center database of patients registered between 1989 and 2011 who were admitted to the intensive care unit of our burn care center after burn or scald injury. Uni-variate statistical analysis was performed comparing two groups (steroid treated vs. non steroid treated patients) with regard to clinical outcome. Main parameters were sepsis, mortality and pulmonary complications such as pneumonia, ALI and ARDS. Multi-variate analysis was used by logistic regression with mortality and pulmonary complications as the dependent variables to identify independent risk factors after burn or scald injuries.

RESULTS

A total of 1637 patients with complete data were included in the present analysis. 199 (12.2%) received single-shot intravenous steroids during the prehospital phase of care. In 133 (66.8%) of these patients, inhalation injury was diagnosed via bronchoscopy. Steroid treated patients had sustained a significantly higher severity of burn than non-steroid treated patients (Abbreviated Burn Severity Index 7.1±3 vs. 6.0±2.9; p<0.001). In a multivariate analysis using a logistic regression model early intravenous steroid treatment had no significant effect on pulmonary complications and mortality.

CONCLUSIONS

In our single center cohort of burned and scalded patients single-shot intravenous steroids during the pre-hospital phase of care was not associated with pulmonary complications or mortality.

Isolated inhalational injury: Clinical course and outcomes in a multidisciplinary intensive care unit

Background and Aims:

Although smoke inhalation is well known to cause acute lung injury, there are few reports in literature that study the evolution, clinical course and outcomes of isolated inhalational lung injury in a modern intensive care setting. A major fire disaster provided us the opportunity to study victims of isolated inhalational injury admitted to our Multidisciplinary Intensive Care Unit (MICU).

Materials and Methods:

We studied the clinical course, ICU and hospital outcomes of 13 victims of a fire disaster who required mechanical ventilation for isolated inhalational lung injury. All patients were followed up at regular intervals, and their functional status was assessed at 8 months after hospital discharge.

Results:

The Lung Injury Scores (LIS) worsened to reach a nadir on Day 3 of injury. There was a significant correlation between the LIS on Day 3 and duration of mechanical ventilation (r = 0.8; P = 0.003), ICU (r = 0.8; P = 0.002) and hospital (r = 0.6; P = 0.02) days. Late-onset airway complications were encountered in four patients. Three of them required long-term artificial airways – two with a tracheostomy while the third patient required surgical insertion of a “T” tube. Persistent problems with phonation occurred in two patients. At 8 months postdischarge, all patients were independent with activities of daily living; all were back to work, except for two who continued to need artificial airways.

Conclusions:

Inhalational lung injury progresses over the first few days and is worst after 72 h. Late-onset airway complications may manifest after several weeks and require repeated intervention.

Acute supraglottitis in adults

OBJECTIVES

Adult supraglottitis is a potentially life-threatening airway infection. We reviewed the management and outcome of supraglottitis in 169 adults admitted to Liverpool Hospital between 1999 and 2009.

METHODS

A retrospective review was conducted of all admissions with supraglottitis in patients at least 18 years of age. The diagnosis was confirmed by fiberoptic nasolaryngoscopy or direct laryngoscopy under general anesthesia. The main outcome measure was the need for intubation or tracheotomy. Univariate analysis was performed to determine factors that led to a worse outcome.

RESULTS

There were 80 men and 89 women in the cohort, with a median age of 51 years. Of these, 140 patients were admitted to the intensive care unit for a mean duration of 2 days. The common symptoms and signs at presentation were odynophagia and dysphagia (94%), dysphonia (65%), and stridor (33%). Endotracheal intubation was performed in 16 patients, and an awake tracheotomy was required in 4 patients. Dexamethasone acetate was used in 103 patients. Thirty-five patients had diabetes mellitus as a comorbidity. The presence of diabetes was predictive of the need for intubation or tracheotomy (p < 0.05), and the use of steroids was predictive of an intensive care unit stay of 24 hours or less (p < 0.05).

CONCLUSIONS

Fiberoptic laryngoscopy is the gold standard for diagnosis of supraglottitis, and close airway monitoring is crucial. Conservative management of the airway is a viable option, but the presence of diabetes makes airway intervention more likely. The use of steroids aids in symptom alleviation and hastens resolution of airway swelling, with no negative sequelae.

Toxicity of smoke extracts towards A549 lung cells: role of acrolein and suppression by carbonyl scavengers

The noxious 3-carbon electrophile acrolein forms on combustion of diverse organic matter including synthetic polymers such as polyethylene. While known to play a key role in smoke inhalation injury (SII), the molecular basis for the pulmonary toxicity of high dose acrolein-containing smoke is unclear. As a result, drug interventions in SII are poorly directed against pathogenetic smoke toxicants such as acrolein. The first aim of this study was to confirm a role for acrolein in the acute toxicity of smoke extracts towards A549 lung cells by monitoring adduction of known acrolein targets and the expression of acrolein-inducible genes. A second aim was to evaluate carbonyl scavengers for their abilities to protect cell targets and block smoke extract toxicity. Extracts were prepared by bubbling smoke released by smouldering polyethylene through a buffered saline-trap. Acrolein levels in the extracts were estimated via HPLC after derivatisation with 2,4-dinitrophenylhydrazine. Extracts were highly toxic towards A549 cells, eliciting greater ATP depletion than an equivalent concentration of acrolein alone. The toxicity was accompanied by pronounced carbonylation of several cytoskeletal targets, namely vimentin and keratins-7, -8 and -18. Western blotting revealed that polyethylene combustion products also upregulated several acrolein-responsive protein markers, including GADD45beta, NQO1, HMOX, Hsp70, Nur77 and Egr1. Several carbonyl scavengers (bisulfite, d-penicillamine, hydralazine and 1-hydrazinoisoquinoline) strongly attenuated smoke extract toxicity, with bisulfite suppressing both the adduction and cross-linking of intermediate filament targets. Bisulfite also suppressed the cytotoxicity of smoke extracts when detected using real-time monitoring of cellular impedance. These findings confirm a key role for acrolein in smoke cytotoxicity and suggest drugs that block acrolein toxicity deserve further investigation as possible interventions against SII.

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.

Inhalation burn injury in children

With advances in burn care, many children are surviving severe burn injuries. Inhalation injury remains a predictor of morbidity and mortality in burn injury. Inhalation of smoke and toxic gases leads to pulmonary complications, including airway obstruction from bronchial casts, pulmonary edema, decreased pulmonary compliance, and ventilation-perfusion mismatch, as well as systemic toxicity from carbon monoxide poisoning and cyanide toxicity. The diagnosis of inhalation injury is suggested by the history and physical exam and can be confirmed by bronchoscopy. Management consists of supportive measures, pulmonary toilet, treatment of pulmonary infection and ventilatory support as needed. This review details the pathophysiology, diagnosis, and management options for inhalation injury.

Early and late complications among 15 victims exposed to indoor fire and smoke inhalation

AIM

To evaluate early and late complications among victims exposed to indoor fire and smoke inhalation.

METHOD

An observational, descriptive and prospective longitudinal study of 15 victims of smoke inhalation admitted to the intensive care unit.

RESULTS

Although without significant burns, 13 of the victims were unconscious, with airway injury, abnormal temperature and hypokalaemia, and underwent mechanical ventilation. Initial carbon monoxide concentration averaged 20.4+/-8.3%, dropping to 3.9+/-3.3% 4h later. On the 1st day, two victims recovered and were transferred, and another two died. Creatine kinase levels (2594+/-2455 U/l) correlated with duration of intensive care. Of the remaining 11 patients, 10 had early pneumonia. Steroid treatment was initiated for four patients receiving prolonged mechanical ventilation, because of persistent fever and dry cough without evidence of infection.

CONCLUSIONS

Mortality and systemic involvement were related to burn of the upper airway and contact with combustion products. Initial creatine kinase levels emerged as a prognostic marker of injury severity. Bronchoscopy was useful in grading airway injury and obtaining bronchoalveolar culture. Corticosteroids were effective, after the acute phase, in treating non-infectious pulmonary complications.