Smoke inhalation: diagnosis and treatment

Protective Effect of Nebulized Heparin in the Animal Models of Smoke Inhalation Injury: A Meta-analysis and Systematic Review of Experimental Studies

The pathophysiological mechanism of abnormal coagulation can result from smoke inhalation injury (SII). Heparin nebulization is a common treatment for lung disorders. This study aimed to use meta-analysis in animal models to examine the effectiveness of atomized heparin on SII. For our online searches, we used the Cochrane Central Register of Controlled Trials, PubMed, Web of Science, Chinese National Knowledge Infrastructure, Chinese BioMedical Literature Database, and Wanfang Database up to January 2022. Data for SII were retrieved and compared to control animals. The studies' findings were determined by combining standardized mean difference (SMD) analysis with 95% confidence intervals (CIs). The findings showed that as compared to the control group, the heparin-treated group had a lower death rate (relative risk 0.42; 95% CI 0.22, 0.80; p < .05). The meta-analysis demonstrated favorable changes in lung physiology, including PaO2/FiO2 (SMD 1.04; 95% CI 0.65, 1.44; p < .001), lung wet-to-dry weight ratio (SMD -1.83; 95% CI -2.47, -1.18; p < .001), and pulmonary shunt Qs/Qt (SMD -0.69; 95% CI -1.29, -0.08; p < .05) after heparin nebulization for lung injury. The present data indicated that pulmonary artery mean pressure in the heparin therapy group was significantly lowered after 24 and 48 hours of therapy, suggesting that the cardiovascular system could recover following heparin treatment. As a result, heparin nebulization appeared to be more effective against SII and improved cardiopulmonary function compared to the control group. Graphical Abstract.

Positive signs on physical examination are not always indications for endotracheal tube intubation in patients with facial burn

Background

After clinical evaluation in the emergency department (ED), facial burn patients are usually intubated to protect their airways. However, the possibility of unnecessary intubation or delayed intubation after admission exists. Objective criteria for the evaluation of inhalation injury and the need for airway protection in facial burn patients are needed.

Methods

Facial burn patients between January 2013 and May 2016 were reviewed. Patients who were and were not intubated in the ED were compared. All the intubated patients received routine bronchoscopy and laboratory tests to evaluate whether they had inhalation injuries. The patients with and without confirmed inhalation injuries were compared. Multivariate logistic regression analysis was used to identify the independent risk factors for inhalation injuries in the facial burn patients. The reasons for intubation in the patients without inhalation injuries were also investigated.

Results

During the study period, 121 patients were intubated in the ED among a total of 335 facial burn patients. Only 73 (60.3%) patients were later confirmed to have inhalation injuries on bronchoscopy. The comparison between the patients with and without inhalation injuries showed that shortness of breath (odds ratio = 3.376, p = 0.027) and high total body surface area (TBSA) (odds ratio = 1.038, p = 0.001) were independent risk factors for inhalation injury. Other physical signs (e.g., hoarseness, burned nostril hair, etc.), laboratory examinations and chest X-ray findings were not predictive of inhalation injury in facial burn patients. All the patients with a TBSA over 60% were intubated in the ED even if they did not have inhalation injuries.

Conclusions

In the management of facial burn patients, positive signs on conventional physical examinations may not always be predictive of inhalation injury and the need for endotracheal tube intubation in the ED. More attention should be given to facial burn patients with shortness of breath and a high TBSA. Airway protection is needed in facial burn patients without inhalation injuries because of their associated injuries and treatments.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12873-022-00594-9.

Nebulized Heparin for Adult Patients With Smoke Inhalation Injury: A Review of the Literature

Objective: To review the clinical effects of nebulized heparin and N-acetylcysteine (NAC) in patients with smoke inhalation injury (IHI) and provide recommendations for use. Data Sources: A search of PubMed, MEDLINE, and Scopus databases was completed from database inception through April 15, 2020, using terms: heparin, acetylcysteine, smoke inhalation injury, and burn injury. Study Selection and Data Extraction: All studies pertaining to efficacy and safety of nebulized heparin and/or NAC for IHI in adult patients were evaluated. Reference lists were reviewed for additional publications. Nonhuman studies, non-English, and case report publications were excluded. Data Synthesis: Eight studies were included. Four demonstrated positive outcomes, 3 demonstrated no benefit or possible harm, and 1 assessed safety. Supporting trials treated patients within 48 hours of injury with 10 000 units of nebulized heparin with NAC for 7 days or until extubation. Two trials with negative findings treated patients within 72 hours, or unspecified, with 5000 units of nebulized heparin with NAC for 7 days, while the third used 25 000 units within 36 hours but was grossly underpowered for analysis. Clinical findings include reduced duration of mechanical ventilation and improved lung function with possible increase risk of pneumonia and no evidence of increased bleeding risk. Conclusions: Nebulized heparin may improve oxygenation and reduce duration of mechanical ventilation in IHI. If nebulized heparin is used, 10 000 units every 4 hours alternating with NAC and albuterol at 4-hour intervals is recommended. Sterile technique should be emphasized. Monitoring for bronchospasm or new-onset pneumonia should be considered.

Inhalation injury caused by cornstarch dust explosion in intubated patients-A single center experience

BACKGROUND

Around 10%-20% of burned patients have inhalation injuries, and the severity of these injuries is correlated with mortality. Fiberoptic bronchoscopy is an important tool for the early diagnosis of inhalation injury. This study investigated correlations between the severity of inhalation injury and outcomes of patients involved in a cornstarch dust explosion in northern Taiwan in 2015.

METHODS

Patients with burns who were intubated after the explosion were enrolled. Their medical records were reviewed, and data including patient characteristics, percentage of total body surface area (%TBSA) burned, severity of the inhalation injury, mechanical ventilation settings, and outcomes were collected and analyzed.

RESULTS

Twenty patients underwent fiberoptic bronchoscopy during the first 24h to evaluate an inhalation injury. Their mean age was 22.4±5.5 years and the mean %TBSA burned was 55.7±19.4%. Fourteen patients had a grade 1 inhalation injury and six had a grade 2 injury. There was a higher %TBSA burned in the grade 1 group than in the grade 2 group, although the difference did not reach statistical significance (60.0±20.3% versus 45.5±13.5%, p=0.129). Compared to the grade 2 group, the grade 1 group had a significantly higher white blood cell count (29.4±9.3 versus 18.6±4.6, p=0.015) and frequency of facial burns (85.7% versus 33.3%, p=0.037). The overall intensive care unit mortality rate was 10% (n=2), with no significant intergroup difference (grade 1, 14.3% versus grade 2, 0%, p=0.192).

CONCLUSION

Although the explosion resulted in a high rate of inhalation injuries in critically ill patients, there was no significant correlation between mortality and the severity of the inhalation injuries.

Current consensus and controversies in major burns management

Most doctors in Britain receive some training in the care of the burned patient, if not as an undergraduate then as part of training in accident and emergency medicine or in the Advanced Trauma Life Support (ATLS®) course. Because major burn injury presents infrequently to the average district hospital, most of this training is rusty by the time it is needed. Further, most have little opportunity to catch up with developments in this very specialized area of trauma medicine.

This paper aims to address some of these shortcomings by describing recent advances in burn care and highlighting areas of current debate. The fluids used for resuscitation, improved options for treatment, the status of ongoing discussions about treatment facilities and the state of the art in managing smoke inhalation are reviewed. Some pointers to the future and to avenues for research are suggested.

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.

Physical therapy performance in the rehabilitation of survivors of the Kiss nightclub tragedy: an experience report

Abstract Introduction : As a result of a fire in the Kiss nightclub that occurred in the city of Santa Maria - RS, 242 people were killed, of whom 235 died on the day of the episode, asphyxiated by the inhalation of toxic smoke. Approximately 1,000 more were injured. Objective : To report the experience of a group of physical therapists, professors at the Federal University of Santa Maria (UFSM), in the rehabilitation of survivors of the fire, victims of burns and inhalation injury. Materials and methods : Quantitative and qualitative study, in which an evaluation protocol of physical functional ability was designed to identify rehabilitation needs. Results : Two hundred seventy patients (147 men, mean age 26.72 ± 9.5 years) were examined, of which approximately 70% had some type of clinical modification or functional impairment that indicated the need for rehabilitation. The most prevalent respiratory signs and symptoms were: dry or productive cough (59.2%); abnormal respiratory pace (11.4%); fatigue (35.92%); dyspnea (17.7%); and chest pain (16.6%). Neurological symptoms such as persistent headache (88.51%), memory loss (11.4%), and paresthesia (8.1%) were also reported. Musculoskeletal injuries (14.7%) and extensive burns (8.8%) were also observed. One hundred and eighty-nine patients were referred to outpatient physical therapy and, of these, 22 still remain at the Outpatient Physical Therapy Unit of the University Hospital of (HUSM). Conclusions : Despite the vast professional experience of this group of physical therapists, the situations experienced were unique and unprecedented, both professionally and personally, and reinforced the importance of joining forces within an emergency care unit, as well as the importance of comprehensive and multi-professional outpatient monitoring.

Pediatric cyanide poisoning by fire smoke inhalation: a European expert consensus. Toxicology Surveillance System of the Intoxications Working Group of the Spanish Society of Paediatric Emergencies

Most fire-related deaths are attributable to smoke inhalation rather than burns. The inhalation of fire smoke, which contains not only carbon monoxide but also a complex mixture of gases, seems to be the major cause of morbidity and mortality in fire victims, mainly in enclosed spaces. Cyanide gas exposure is quite common during smoke inhalation, and cyanide is present in the blood of fire victims in most cases and may play an important role in death by smoke inhalation. Cyanide poisoning may, however, be difficult to diagnose and treat. In these children, hydrogen cyanide seems to be a major source of concern, and the rapid administration of the antidote, hydroxocobalamin, may be critical for these children.European experts recently met to formulate an algorithm for prehospital and hospital management of adult patients with acute cyanide poisoning. Subsequently, a group of European pediatric experts met to evaluate and adopt that algorithm for use in the pediatric population.

The acute pulmonary inflammatory response to the graded severity of smoke inhalation injury

OBJECTIVES

To determine whether the graded severity of smoke inhalation is reflected by the acute pulmonary inflammatory response to injury.

DESIGN

In a prospective observational study, we assessed the bronchoalveolar lavage fluid for both leukocyte differential and concentration of 28 cytokines, chemokines, and growth factors. Results were then compared to the graded severity of inhalation injury as determined by Abbreviated Injury Score criteria (0, none; 1, mild; 2, moderate; 3, severe; 4, massive).

SETTING

All patients were enrolled at a single tertiary burn center.

PATIENTS

The bronchoalveolar lavage fluid was obtained from 60 patients within 14 hrs of burn injury who underwent bronchoscopy for suspected smoke inhalation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Those who presented with worse grades of inhalation injury had higher plasma levels of carboxyhemoglobin and enhanced airway neutrophilia. Patients with the most severe inhalation injuries also had a greater requirement for tracheostomy, longer time on the ventilator, and a prolonged stay in the intensive care unit. Of the 28 inflammatory mediators assessed in the bronchoalveolar lavage fluid, 21 were at their highest in those with the worst inhalation injury scores (grades 3 and 4), the greatest of which was interleukin-8 (92,940 pg/mL, grade 4). When compared in terms of low inhalation injury (grades 1-2) vs. high inhalation injury (grades 3-4), we found significant differences between groups for interleukin-4, interleukin-6, interleukin-9, interleukin-15, interferon-γ, granulocyte-macrophage colony-stimulating factor, and monocyte chemotactic protein-1 (p < .05 for all).

CONCLUSIONS

These data reveal that the degree of inhalation injury has basic and profound effects on burn patient morbidity, evokes complex changes of multiple alveolar inflammatory proteins, and is a determinant of the pulmonary inflammatory response to smoke inhalation. Accordingly, future investigations should consider inhalation injury to be a graded phenomenon.

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.

A model for predicting mortality among critically ill burn victims

OBJECTIVE

To develop a model for predicting mortality among burn victims.

METHODS

All casualties admitted to our intensive care burn unit (ICBU) with a diagnosis of thermal or inhalation injury were studied. Age, total and full-thickness body surface area (BSA) burned, presence of inhalation injury, gender, mechanism of injury, delay to ICBU admission and mechanical ventilation during the first 72 h were recorded. The 851 participants were randomly divided into derivation (671) and validation (180) sets. From univariate and multivariate logistic regression analyses a mortality predictive equation was derived.

RESULTS

Mortality was 17.6%. In univariate analysis, all variables were significantly associated with mortality except mechanism of injury and delay to ICBU admission. In multivariate analysis, age, total and full-thickness BSA burned, female gender and early mechanical ventilation were independently associated with mortality.

CONCLUSIONS

We propose a mortality predictive equation for burned victims. In this model, MV and not inhalation injury is a mortality risk factor.

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.

Inhalation injury, pulmonary perturbations, and fluid resuscitation

Inhalation injury (INHI) associated with thermal injury has been shown to increase the rate of mortality. Several investigators have shown that patients with inhalation and burn injuries will require increased fluid volumes during acute resuscitation when compared with patients with burn injury alone. Other groups have examined the use of lung compliance and airway resistance as predictors of outcome in patients with INHI. We hypothesized that increased fluid requirements would more closely correlate with perturbations in pulmonary performance than with mere presence or absence of INHI or the degree of injury by bronchoscopic criteria. We performed a retrospective chart review during a period of 3 years. We identified 80 patients with suspected INHI that required intubation, mechanical ventilation, and fiber optic bronchoscopy in the first 24 hours of their admission. Variables collected included age, sex, weight and %TBSA burned, as well as blood alcohol level, the presence of head and neck burns and escharotomies, and admission carbon monoxide levels. Patients were classified into five groups according to a grading system of INHI (0, 1, 2, 3, and 4), derived from findings at initial bronchoscopy and based on AIS criteria. The following pulmonary parameters were noted at regular intervals: mode of ventilation, tidal volume, peak inspiratory pressures, mean airway pressures, and compliance. The P:F ratio also was recorded at regular intervals. Total fluid volume infused was noted at 0-, 24-, and 48-hour intervals, and was calculated as ml/kg/%TBSA. Outcomes were measured by in-hospital survival, ventilator days, intensive care unit days, and total length of stay. Patients were well matched for %TBSA among the different bronchoscopic grades of INHI, and those with grades 2, 3, and 4 injuries had a significantly worse survival than those with grades 0 or 1 (P = .03). However, grades 2, 3, and 4 did not have increased acute fluid requirements when compared with grades 1 and 2 injuries. Initial pulmonary compliance likewise did not correlate with acute fluid requirements. However, those patients with a P:F ratio less than 350 at presentation had a statistically significant increase in ml/kg/%TBSA compared with those with P:F >350 (P = .03). They did not have more ventilator days or a statistically worse survival. Fiber optic bronchoscopy is useful in the diagnosis of INHI, and overall survival is worse in those patients with worse grades of injury by bronchoscopic criteria. However, the P:F ratio may be a more accurate predictor of increased fluid requirements during the acute resuscitation.

Continuous nebulized albuterol attenuates acute lung injury in an ovine model of combined burn and smoke inhalation

OBJECTIVE

Albuterol, due to its bronchodilatory and anti-inflammatory effects, is given via continuous nebulization in children with severe asthma. Combined burn and smoke inhalation injury frequently results in acute lung injury due to a combination of airway obstruction and inflammation. We hypothesized that albuterol administered via continuous nebulization would mitigate acute lung injury after smoke inhalation injury and burn.

DESIGN

Randomized prospective animal model.

SUBJECTS

Twenty adult female sheep (mean weight, 33.1+/-0.9 kg).

INTERVENTIONS

Adult ewes were subjected to a 40% body surface area third-degree flame burn and smoke inhalation injury after tracheostomy. Sheep were allocated to a) sham group, b) saline continuous nebulization group, c) 20 mg of albuterol continuous nebulization group, or d) 40 mg of albuterol continuous nebulization group (n=5 animals per group). All groups received intravenous lactated Ringer's solution at 4 mL.kg-1.%burn(-1).24 hrs-1 for resuscitation and were equally mechanically ventilated throughout the 48-hr study period. Pulmonary and cardiac function, lung lymph flow, bronchial obstruction score, and wet/dry lung weights were recorded.

RESULTS

Compared with saline and control groups, the albuterol groups had lower pause and peak inspiratory pressures, decreased pulmonary transvascular fluid flux, a significantly higher Pao2/Fio2 ratio, and decreased shunt fraction at 48 hrs postinjury. The wet-to-dry lung weight ratio and bronchial obstruction scores were lower for sheep receiving albuterol.

CONCLUSIONS

Continuous nebulization of albuterol improves pulmonary function via improved airway clearance and decreased fluid flux in a combined burn/smoke inhalation injury model.

Early laryngeal inhalation injury and its correlation with late sequelae

OBJECTIVE

Inhalation injury can permanently alter normal laryngeal function. The aim of this study was to examine the early changes in voice, swallowing, and breathing in laryngeal inhalation injuries.

STUDY DESIGN

This was a prospective analysis of nine patients with inhalation injuries at a tertiary care institution.

METHODS

Laryngeal function of patients admitted for inhalation injury requiring intubation was documented using videostroboscopy and swallowing evaluation by the speech pathology service. Bronchoscopy was used to classify the degree of inhalation injury. Association among total body surface area, facial burns, severity of laryngotracheal injuries, and loss of function was attempted.

RESULTS

All three patients with severe tracheal inhalation injury presented persistent hoarseness at 1-year follow up with abnormal videostroboscopy findings. No association was found between inhalation injury and total body surface area burned. None of the patients in this series presented permanent swallowing dysfunction.

CONCLUSION

The otolaryngologist plays an important role in the initial and long-term management of inhalation injuries. Inhalation injuries should be managed in a multidisciplinary fashion. There may be a correlation between the degree of tracheal injury and laryngeal injury and hoarseness.

Factors that Predict the Need for Intubation in Patients with Smoke Inhalation Injury

Early identification of smoke inhalation patients who will require intubation is crucial. We conducted a retrospective chart review to identify predictors of respiratory distress in patients who present with smoke inhalation injury. Our study involved 41 patients who had been treated in the emergency room at a regional burn center. Eight of these patients required intubation. Intubation was positively correlated with physical examination findings of soot in the oral cavity (p < 0.001), facial burns (p = 0.025), and body burns (p = 0.025). The need for intubation was also predicted by fiberoptic laryngoscopic findings of edema of either the true vocal folds (p < 0.001) or the false vocal folds (p < 0.01). No statistically significant correlation was found between intubation and any of the classic symptoms of smoke inhalation: stridor, hoarseness, drooling, and dysphagia (all p = 1.0). Also, multivariate analysis revealed that facial burns correlated significantly with edema of the true vocal folds (p = 0.01) and body burns correlated significantly with edema of both the true (p = 0.047) and false (p = 0.003) vocal folds. We conclude that patients with soot in the oral cavity, facial burns, and/or body burns should be monitored closely because these findings indicate a higher likelihood of laryngeal edema and the need for intubation.

Is high PEEP low volume ventilation in burn patients beneficial? A retrospective study of 61 patients

In burn care lung damage by inhalation injury is a major cause of mortality in burn patients. In the field of intensive care medicine ventilation strategies to reduce lung injury caused by ventilation are under investigation. The promising results of the application of pressure controlled high PEEP low volume (HPLV) ventilation prompted us to use this ventilation strategy in our burn ICU. To establish whether this ventilation regime is beneficial the charts of 61 consecutive patients needing artificial respiration were reviewed. A scoring system for PEEP level and tidal volume was developed and treatment groups with high PEEP and low volume and low PEEP high volume regimes were compared. No statistically significant differences could be found when comparing treatment versus mortality, the number of pulmonary complications or incidence of pneumothoraces. However, the trend showed a benefit in mortality for patients with an ABSI scoring up to 9, but at the same time pulmonary complications increase. The Horovitz oxygenation index showed no advantage for the HPLV Group. In a separate analysis we found a significant correlation between absolute PEEP and mortality. The correlation between PEEP level and mortality is a dynamic factor predicting outcome, This not been described yet and can be an addition to the static ABSI score. Differences between ventilation strategies were not as evident as expected in this retrospective study, so prospective randomized studies are needed.

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.

Effects of burns on inhalation injury in sheep: a 5-day study

BACKGROUND

We have previously reported that infliction of thermal injury immediately after smoke exposure did not accentuate pulmonary dysfunction during the subsequent 48 h. The purpose of this study was to determine whether thermal injury would aggravate pulmonary dysfunction during a longer postinjury period of 5 days.

METHODS

Six sheep (G1) received 12 units of smoke inhalation injury (SII) alone; seven sheep (G2) received a 40% full-thickness scald burn immediately after SII. All sheep were resuscitated with lactated Ringer's solution for the first 48 h. After 48 h, animals were fed food and water ad libitum. Cardiopulmonary variables and blood gases were measured serially. At the end of the 5-day experimental period, VA/Q distribution was analyzed using the multiple inert gas elimination technique (MIGET). Lung wet to dry (W/D) weight ratios and malondialdehyde (MDA) concentrations were determined.

RESULTS

Cardiac index in G2 significantly increased and remained higher compared with G1. There was no difference in A-aDO(2) between the two groups. There was also no difference between the two groups by MIGET study, or in terms of lung MDA and W/D weight ratios. None of the animals manifested symptoms of infection.

CONCLUSION

Despite the difference in the hemodynamic changes induced by the addition of a 40% burn to smoke inhalation injury, pulmonary dysfunction was not accentuated during the 5-day study period in the absence of infection.

Pathophysiological analysis of combined burn and smoke inhalation injuries in sheep

We investigated the pathophysiological alterations seen with combined burn and smoke inhalation injuries by focusing on pulmonary vascular permeability and cardiopulmonary function compared with those seen with either burn or smoke inhalation injury alone. To estimate the effect of factors other than injury, the experiments were also performed with no injury in the same experimental setting. Lung edema was most severe in the combined injury group. Our study revealed that burn injury does not affect protein leakage from the pulmonary microvasculature, even when burn is associated with smoke inhalation injury. The severity of lung edema seen with the combined injury is mainly due to augmentation of pulmonary microvascular permeability to fluid, not to protein. Cardiac dysfunction after the combined injury consisted of at least two phases. An initial depression was mostly related to hypovolemia due to burn injury. It was improved by a large amount of fluid resuscitation. The later phase, which was indicated to be a myocardial contractile dysfunction independent of the Starling equation, seemed to be correlated with smoke inhalation injury.

Facial burns in children: a series analysis with implications for resuscitation and forensic odontology

This study comprises a continuous (1981-1995) unselected series of all children who died from thermal injuries in the State of Queensland, Australia. One hundred and six children, so identified, died from incineration (35 per cent), respiratory burns with smoke or carbon monoxide inhalation (33 per cent), body surface area burns comprising greater than 60 per cent (9 per cent) and electrocution (20 per cent). The burn fatality rate was 0.98 per hundred thousand children (0-14 years) per year, with no secular trend and, specifically, no reduction in the annual rate of such fatalities. Eighty-two children (49 males) had concomitant facial injuries, both thermal and nonthermal; of whom 55 per cent were under the age of five years. Sixty (73 per cent) child burn victims died in house fires. Forensic odontology is important in confirming the age of such victims in single incinerations but is of limited value when larger numbers of children are incinerated, because of the relative lack of dental restorations in the infant and pre-school age group. Of the 82 children with facial and airway injuries, 12 per cent had only mild or superficial facial damage and only seven (8 per cent) were alive or resuscitable at the time of rescue from the conflagration or burning injury. child deaths from burns contributed an annual loss rate of 506 years of potential life lost (YPLL) in a population of 3 million of whom 21.5 per cent were children under the age of 15 years. Airway management and resuscitation, in the context of managing surviving burn victims of any age with facial injuries, pose special difficulties. Inhalational burns (smoke and the gases of conflagration) result in a mortality greater than 60 per cent. Although 81 per cent of children showed evidence of airway obstruction, analysis of current data indicates that a maximum of 8 per cent could have survived with airway maintenance and protection. Inhalational burns (to both upper and lower airways) grossly reduce survivability. Primary prevention would seem vital and thus remains a major challenge to reduce the incidence of such deaths. Some strategies include advocacy to promote the compulsory installation of smoke alarms, family drills to practise escape and the teaching of 'first aid for all'

Intrabronchial surfactant application in cases of inhalation injury: first results from patients with severe burns and ARDS

Damage to the respiratory tract caused by inhalation of toxic products of combustion with subsequent development of an acute respiratory distress syndrome (ARDS) is one of the main causes of death in burn patients. Treatment with an exogenous surfactant is a therapeutic option for which there has previously been no empirical data. We report on four severely burned patients with deep partial thickness and full thickness burns of between 40 and 70 per cent body surface area (BSA), and with inhalation injury complicated by ARDS. These patients were treated once or more than once with bovine surfactant replacement (Alveofact). In addition to biophysical and biochemical analysis, the influence of this substance on oxygenation and lung function were evaluated. After the limits of mechanical ventilation had been reached, bronchoscopic intrabronchial administration of surfactant was followed by temporarily improved gas exchange with an increase in arterial O2 partial pressure (PaO2), accompanied by a reduction in inspiratory O2 concentration (FiO2), and also improved lung compliance. All the patients survived in spite of an initially unfavourable prognosis. Replacement of exogenous surfactant in the treatment of inhalation traumatized severe burn patients with ARDS appears to show considerable promise as an approach to improving the survival chances of these high-risk patients.

Effects of burns on inhalation injury

BACKGROUND

There are few studies of smoke injury combined with thermal burn.

METHODS

Seven sheep (G1) received smoke injury alone; eight (G2) received a 40% full-thickness scald burn immediately after smoke injury. All animals were resuscitated with lactated Ringer's solution and killed 48 hours after injury. Cardiopulmonary variables and blood gases were measured serially. Ventilation perfusion distribution was analyzed using the multiple inert gas elimination technique. Lung wet to dry weight ratio and malondialdehyde levels were determined.

RESULTS

G2 resulted in early significant hemodynamic changes. Serum total protein concentration was significantly lower and malondialdehyde significantly higher in G2. However, PaO2, lung wet to dry weight ratio, and ventilation perfusion mismatching in G2 did not differ from those in G1.

CONCLUSIONS

Although the addition of burn injury exaggerated the lung lipid peroxidation and hypoproteinemia in the presence of more pronounced hemodynamic changes, the pulmonary dysfunction was not accentuated.

Anesthesia and pain management in pediatric burn patients

Patients with severe burn injury are a challenge for the pediatric anesthesiologist. Today with adequate care many children survive their trauma and have a good chance for complete functional and psychological rehabilitation. The anesthesiologist has to provide excellent care even for patients in suboptimal or unstable condition to enable wound debridement and grafting, because only rapid skin closure will stabilize the patient. Adequate pain treatment during all phases of burn treatment is mandatory.

Early complications and value of initial clinical and paraclinical observations in victims of smoke inhalation without burns

OBJECTIVE

To evaluate the incidence of early pulmonary complications and the value of initial clinical signs and paraclinical investigations in victims of smoke inhalation not suffering from burns following structural fires.

DESIGN

Retrospective chart review.

SETTING

Thirteen-bed ICU.

PATIENTS

Sixty-four victims of smoke inhalation following household fires were admitted to the ICU between January 1987 and December 1992. Exclusion criteria from the study were patients with cutaneous burns or multiple trauma or blast injury, and patients found in cardiac arrest.

METHODS

Clinical, biological, and radiologic parameters were collected over a 5-day period.

RESULTS

The mortality rate in relation to progressive respiratory failure was 3.1%. Mean ICU stay was 5.8 days (range, 1 to 33 days), and was longer in the patients presenting with soot deposits in the oropharynx (p = 0.02), dysphonia (D) (p = 0.05), or ronchi (R) (p = 0.0004) at the first examination, and in those having a positive sputum bacteriologic analysis (p = 0.003) or requiring parenteral bronchodilator agents for more than 24 h (p = 0.04). Thirty-five patients underwent mechanical ventilation (MV) for a mean of 101.2 h (range, 8 to 648 h). Mean MV duration was higher in the patients presenting initially with R (p = 0.003), high carbon monoxide (but not cyanide) levels (p = 0.02), or a positive bacteriologic sample (p = 0.0001). Positive bacteriologic sampling correlated with the presence of D (p = 0.02) or R (p = 0.04) and with immediate intubation (p = 0.0003). No correlation was found with chest radiograph.

CONCLUSIONS

In this selected series of fire victims without cutaneous burns, respiratory injury was frequent. The initial clinical signs may be helpful to predict pulmonary complications.

Pre-hospital strategy for therapeutic intervention of fire victims

Fire victims are exposed to the triple threat of thermal injury (skin and lungs), smoke toxicity (toxic or irritant gases and soots) and even trauma whose occurrences are somewhat independent one from the other but whose addition does sharply increase the probability of death of the victims. As the different victims of the same fire may not suffer from the same injuries, this triple threat must be looked for in each fire victim.