Prevalence and prognostic impact of inhalation injury among burn patients: A systematic review and meta-analysis

"To BAL or not to BAL, that is the question": Variations in smoke inhalation injury guidelines from burn units and centres in England, Scotland and Wales

AIM

To evaluate variations in diagnostic criteria and management recommendations for smoke inhalation injury (SII) amongst the burn networks of England, Scotland, and Wales.

METHODS

A descriptive cross-sectional study examining SII guidelines provided by adult burn units and centres in England, Scotland and Wales.

RESULTS

All 16 adult burn units and centres responded. Fourteen (87.5 %) had guidelines. Due to sharing of guidelines, ten unique guidelines were assessed. Diagnostic criteria showed variability with no universal criterion shared amongst guidelines. Bronchoscopy was recommended by 90 % of guidelines, but the timing varied. The use of bronchoscopic scoring systems was recommended by four guidelines. Bronchoalveolar lavage (BAL) was recommended by four, with considerable variation in frequency and choice of lavage fluid. All guidelines advised at least one nebulised agent: heparin (n = 8); N-acetyl cysteine (NAC) (n = 8); or salbutamol (n = 8). All guidelines included advice on carbon monoxide poisoning; however, carboxyhaemoglobin (COHb) cut-off levels for treatment varied (5 % [n-4], 10 % [n = 3], 15 % [n = 1]). All recommended high-flow oxygen. Seven (70 %) guidelines offered guidance on cyanide poisoning. Reduced/altered consciousness was the only consistent diagnostic criterion. Five (50 %) guidelines provided intubation guidance, emphasising the role of a 'senior clinician' as the intubator. Ventilatory guidance appeared in eight guidelines, focusing on lung protective ventilation (n = 8); oxygenation goals (n = 3); and permissive hypercapnia (n = 3). Within lung-protective ventilation, advice on tidal volume (6, or 6-8 ml/kg) and plateau pressures (>30 cmH2O) were presented most commonly (n = 7).

CONCLUSION

This study has outlined the substantial variations in guidance for the management of SII. The results underscore the need for a national guideline outlining a standardised approach to the diagnosis and management of SII, within the limitations of the current evidence.

Prophylactic Systemic Antibiotic and Systemic Glucocorticoid Therapy After Burn Inhalation Injury: A Report of Two Cases and Review of Literature

Burn inhalation injury is a significant risk factor for mortality in burn patients. Despite the considerable progress made in the treatment of burn inhalation injury, there remains no consensus on the appropriate course of treatment, leading to ongoing controversy regarding the use of prophylactic systemic antibiotics and systemic glucocorticoids. This study presents two cases of burn inhalation injury diagnosed by fiberoptic bronchoscopy and treated with systemic glucocorticoids and prophylactic systemic antibiotics. By conducting a literature review, this study aimed to discuss the application of systemic glucocorticoids and prophylactic systemic antibiotics in patients with burn inhalation injuries. The suitability of prophylactic systemic antibiotics and systemic glucocorticoids for treating burn inhalation injury patients necessitates a comprehensive assessment of the patient's condition and an accurate judgment of the course of their disease.

An international RAND/UCLA expert panel to determine the optimal diagnosis and management of burn inhalation injury

BACKGROUND

Burn inhalation injury (BII) is a major cause of burn-related mortality and morbidity. Despite published practice guidelines, no consensus exists for the best strategies regarding diagnosis and management of BII. A modified DELPHI study using the RAND/UCLA (University of California, Los Angeles) Appropriateness Method (RAM) systematically analysed the opinions of an expert panel. Expert opinion was combined with available evidence to determine what constitutes appropriate and inappropriate judgement in the diagnosis and management of BII.

METHODS

A 15-person multidisciplinary panel comprised anaesthetists, intensivists and plastic surgeons involved in the clinical management of major burn patients adopted a modified Delphi approach using the RAM method. They rated the appropriateness of statements describing diagnostic and management options for BII on a Likert scale. A modified final survey comprising 140 statements was completed, subdivided into history and physical examination (20), investigations (39), airway management (5), systemic toxicity (23), invasive mechanical ventilation (29) and pharmacotherapy (24). Median appropriateness ratings and the disagreement index (DI) were calculated to classify statements as appropriate, uncertain, or inappropriate.

RESULTS

Of 140 statements, 74 were rated as appropriate, 40 as uncertain and 26 as inappropriate. Initial intubation with ≥ 8.0 mm endotracheal tubes, lung protective ventilatory strategies, initial bronchoscopic lavage, serial bronchoscopic lavage for severe BII, nebulised heparin and salbutamol administration for moderate-severe BII and N-acetylcysteine for moderate BII were rated appropriate. Non-protective ventilatory strategies, high-frequency oscillatory ventilation, high-frequency percussive ventilation, prophylactic systemic antibiotics and corticosteroids were rated inappropriate. Experts disagreed (DI ≥ 1) on six statements, classified uncertain: the use of flexible fiberoptic bronchoscopy to guide fluid requirements (DI = 1.52), intubation with endotracheal tubes of internal diameter < 8.0 mm (DI = 1.19), use of airway pressure release ventilation modality (DI = 1.19) and nebulised 5000IU heparin, N-acetylcysteine and salbutamol for mild BII (DI = 1.52, 1.70, 1.36, respectively).

CONCLUSIONS

Burns experts mostly agreed on appropriate and inappropriate diagnostic and management criteria of BII as in published guidance. Uncertainty exists as to the optimal diagnosis and management of differing grades of severity of BII. Future research should investigate the accuracy of bronchoscopic grading of BII, the value of bronchial lavage in differing severity groups and the effectiveness of nebulised therapies in different severities of BII.

Non-Survival Distributions in Paediatric Burn Patients; A Comparative Study of Two National Databases

A contemporary, age-specific model for the distribution of burn mortality in children has not been developed for over a decade. Using data from TriNetX, a global federated health research network, and the American Burn Association's Nation Burn Repository (NBR), we investigated non-survival distributions for paediatric burns in the United States. Paediatric burn patients ages 0-20 between 2010-2020 were identified in TriNetX from 41 Health Care Organizations using ICD-10 codes (T.20-T.30) and identified as lived/died. These were compared to the non-survival data from 90 certified burn centers in NBR database between 2016-2018. The patient population was stratified by age into subgroups of 0-4, 5-9, 10-14, 15-20 years. Overall, mortality rates for paediatric burn patients were found to be .62% in NBR and .52% in TrinetX. Boys had a higher incidence of mortality than girls in both databases (0.34% vs. 0.28% NBR, p = 0.13; 0.31% vs. 0.21% TriNetX, p = <0.001). Comparison of ethnic cohorts between 2010-2015 and 2016-2020 subgroups showed that non-survival rates of African American children increased relative to White children (TriNetX, p = <0.001), however, evidence was insufficient to conclude that African American children die more frequently than other ethnicities (NBR, p=0.054). When analyzing subgroups in TriNetX, burned children ages 5-9 had significantly increased frequency of non-survival, (p = <0.001). However, NBR data suggested that children 0-4 experience the highest frequency of mortality (p = <0.001). The non-survival distributions between these two large databases accurately reflects non-survival rates in burned children.

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.