Acute Respiratory Distress Syndrome in Burn Patients: A Comparison of the Berlin and American-European Definitions

The First 24 Hours: Burn Shock Resuscitation and Early Complications

Resuscitation is required for the management of patients with severe thermal injury. Some of the initial pathophysiologic events following burn injury include an exaggerated inflammatory state, injury to the endothelium, and increased capillary permeability, which all culminate in shock. Understanding these processes is critical to the effective management of patients with burn injuries. Formulas predicting fluid requirements during burn resuscitation have evolved over the past century in response to clinical experience and research efforts. Modern resuscitation features individualized fluid titration and monitoring along with colloid-based adjuncts. Despite these developments, complications from over-resuscitation still occur.

The Complexity of the Post-Burn Immune Response: An Overview of the Associated Local and Systemic Complications

Burn injury induces a complex inflammatory response, both locally and systemically, and is not yet completely unravelled and understood. In order to enable the development of accurate treatment options, it is of paramount importance to fully understand post-burn immunology. Research in the last decades describes insights into the prolonged and excessive inflammatory response that could exist after both severe and milder burn trauma and that this response differs from that of none-burn acute trauma. Persistent activity of complement, acute phase proteins and pro- and anti-inflammatory mediators, changes in lymphocyte activity, activation of the stress response and infiltration of immune cells have all been related to post-burn local and systemic pathology. This "narrative" review explores the current state of knowledge, focusing on both the local and systemic immunology post-burn, and further questions how it is linked to the clinical outcome. Moreover, it illustrates the complexity of post-burn immunology and the existing gaps in knowledge on underlying mechanisms of burn pathology.

A Systematic Review and Meta-Analysis of Extracorporeal Membrane Oxygenation in Patients with Burns

BACKGROUND

Severely burned patients are at high risk for cardiopulmonary failure. Promising studies have stimulated interest in using extracorporeal membrane oxygenation as a potential therapy for burn patients with refractory cardiac and/or respiratory failure. However, the findings from previous studies vary.

METHODS

In this study, the authors conducted a systematic review and meta-analysis using standardized mortality ratios to elucidate the benefits associated with the use of extracorporeal membrane oxygenation in patients with burn and/or inhalation injuries. A literature search was performed, and clinical outcomes in the selected studies were compared.

RESULTS

The meta-analysis found that the observed mortality was significantly higher than the predicted mortality in patients receiving extracorporeal membrane oxygenation (standardized mortality ratio, 2.07; 95 percent CI, 1.04 to 4.14). However, the subgroup of burn patients with inhalation injuries had lower mortality rates compared to their predicted mortality rates (standardized mortality ratio, 0.95; 95 percent CI, 0.52 to 1.73). Other subgroup analyses reported no benefits from extracorporeal membrane oxygenation; however, these results were not statistically significant. Interestingly, the pooled standardized mortality ratio values decreased as the selected patients' revised Baux scores increased (R = -0.92), indicating that the potential benefits from the treatment increased as the severity of patients with burns increased.

CONCLUSIONS

The authors' meta-analysis revealed that burn patients receiving extracorporeal membrane oxygenation treatment were at a higher risk of death. However, select patients, including those with inhalation injuries and those with revised Baux scores over 90, would benefit from the treatment. The authors suggest that burn patients with inhalation injuries or with revised Baux scores exceeding 90 should be considered for the treatment and early transfer to an extracorporeal membrane oxygenation center.

Incidence and Mortality of Acute Respiratory Distress Syndrome in Patients With Burns: A Systematic Review and Meta-Analysis

Objective: We conducted a systematic review and meta-analysis to comprehensively estimate the incidence and mortality of acute respiratory distress syndrome (ARDS) in overall and subgroups of patients with burns. Data sources: Pubmed, Embase, the Cochrane Library, CINAHL databases, and China National Knowledge Infrastructure database were searched until September 1, 2021. Study selection: Articles that report study data on incidence or mortality of ARDS in patients with burns were selected. Data extraction: Two researchers independently screened the literature, extracted data, and assessed the quality. We performed a meta-analysis of the incidence and mortality of ARDS in patients with burns using a random effects model, which made subgroup analysis according to the study type, inclusion (mechanical ventilation, minimal burn surface), definitions of ARDS, geographic location, mean age, burn severity, and inhalation injury. Primary outcomes were the incidence and mortality of burns patients with ARDS, and secondary outcomes were incidence for different subgroups. Data synthesis: Pooled weighted estimate of the incidence and mortality of ARDS in patients with burns was 0.24 [95% confidence interval (CI)0.2-0.28] and 0.31 [95% CI 0.18-0.44]. Incidences of ARDS were obviously higher in patients on mechanical ventilation (incidence = 0.37), diagnosed by Berlin definition (incidence = 0.35), and with over 50% inhalation injury proportion (incidence = 0.41) than in overall patients with burns. Patients with burns who came from western countries and with inhalation injury have a significantly higher incidence of ARDS compared with those who came from Asian/African countries (0.28 vs. 0.25) and without inhalation injury (0.41 vs. 0.24). Conclusion: This systematic review and meta-analysis revealed that the incidence of ARDS in patients with burns is 24% and that mortality is as high as 31%. The incidence rates are related to mechanical ventilation, location, and inhalation injury. The patients with burns from western countries and with inhalation injury have a significantly higher incidence than patients from Asian/African countries and without inhalation injury. Systematic Review Registration: identifier: CRD42021144888.

Acute respiratory distress syndrome caused by carbon monoxide poisoning and inhalation injury recovered after extracorporeal membrane oxygenation along with direct hemoperfusion with polymyxin B-immobilized fiber column: a case report

BACKGROUND

Inhalation injury from smoke or chemical products and carbon monoxide poisoning are major causes of death in burn patients from fire accidents. Respiratory tract injuries from inhalation injury and carbon monoxide poisoning can lead to acute respiratory distress syndrome and cytokine storm syndrome. In the case of acute respiratory failure needing mechanical ventilation accompanied by cytokine storm, mortality is high and immediate adequate treatment at the emergency department is very important.

CASE PRESENTATION

This report describes a case of acute respiratory distress syndrome and cytokine storm followed by carbon monoxide poisoning in a 34-year-old Korean male patient who was in a house fire, and was successfully treated by extracorporeal membrane oxygenation and direct hemoperfusion with polymyxin B-immobilized fiber column at emergency department.

CONCLUSIONS

To prevent mortality in acute respiratory distress syndrome with cytokine storm from inhalation injury and to promote a better prognosis, we suggest that early implication of extracorporeal membranous oxygenation along with direct hemoperfusion with polymyxin B-immobilized fiber column even at the emergency department should be considered.

Changes of Extravascular Lung Water as an Independent Prognostic Factor for Early Developed ARDS in Severely Burned Patients

An important feature of acute respiratory distress syndrome (ARDS) is fluid lost into the interstitium of lung combined with its compromised reabsorption, resulting in the elevation of extravascular lung water (EVLW). Although ARDS is known as an early, common, and life-threatening complication in major burns, the issue of whether or how the EVLW index (EVLWI) correlates with its prognosis has not been identified yet. In this retrospectively study, 121 severely burned adults with ARDS occurred in 2 weeks postburn were analyzed and divided into two groups: survivors (73 patients) and nonsurvivors (48 patients) according to the 28-day outcome after injury. Compared with nonsurvivors, survivors exhibited bigger EVLWI reduction in day 2 after ARDS onset (ΔEVLWI2), with no differences in ARDS timing and other EVLWI variables. ΔEVLWI2, rather than EVLWI on 2 days after ARDS onset, was identified as an independent prognostic factor even after adjusting other significant factors by Cox proportional hazard analysis. ROC curve analysis showed that ΔEVLWI2 [AUC = 0.723, 95% CI = (0.631-0.816), P < .001] was a relative predictor for survival on 28-day postburn, with a threshold of 1.9 ml/kg (63.0% sensitivity, 77.1% specificity). Kaplan-Meier survival curve analysis confirmed a significantly higher survival rate on 28-day postburn in patients with ΔEVLWI2 > 1.9 ml/kg (log-rank test: χ 2 =14.780, P < .001). Taken together, our study demonstrated that ΔEVLWI2 is an independent prognostic factor for early ARDS in severe burns. ΔEVLWI2 higher than 1.9 ml/kg might predict a higher survival rate in those patients.

Simulated aeromedical evacuation exacerbates burn induced lung injury: targeting mitochondrial DNA for reversal

BACKGROUND

Aeromedical evacuation of patients with burn trauma is an important transport method in times of peace and war, during which patients are exposed to prolonged periods of hypobaric hypoxia; however, the effects of such exposure on burn injuries, particularly on burn-induced lung injuries, are largely unexplored. This study aimed to determine the effects of hypobaric hypoxia on burn-induced lung injuries and to investigate the underlying mechanism using a rat burn model.

METHODS

A total of 40 male Wistar rats were randomly divided into four groups (10 in each group): sham burn (SB) group, burn in normoxia condition (BN) group, burn in hypoxia condition (BH) group, and burn in hypoxia condition with treatment intervention (BHD) group. Rats with 30% total body surface area burns were exposed to hypobaric hypoxia (2000 m altitude simulation) or normoxia conditions for 4 h. Deoxyribonuclease I (DNase I) was administered systemically as a treatment intervention. Systemic inflammatory mediator and mitochondrial deoxyribonucleic acid (mtDNA) levels were determined. A histopathological evaluation was performed and the acute lung injury (ALI) score was determined. Malonaldehyde (MDA) content, myeloperoxidase (MPO) activity, and the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome level were determined in lung tissues. Data among groups were compared using analysis of variance followed by Tukey's test post hoc analysis.

RESULTS

Burns resulted in a remarkably higher level of systemic inflammatory cytokines and mtDNA release, which was further heightened by hypobaric hypoxia exposure (P < 0.01). Moreover, hypobaric hypoxia exposure gave rise to increased NLRP3 inflammasome expression, MDA content, and MPO activity in the lung (P < 0.05 or P < 0.01). Burn-induced lung injuries were exacerbated, as shown by the histopathological evaluation and ALI score (P < 0.01). Administration of DNase I markedly reduced mtDNA release and systemic inflammatory cytokine production. Furthermore, the NLRP3 inflammasome level in lung tissues was decreased and burn-induced lung injury was ameliorated (P < 0.01).

CONCLUSIONS

Our results suggested that simulated aeromedical evacuation further increased burn-induced mtDNA release and exacerbated burn-induced inflammation and lung injury. DNase I reduced the release of mtDNA, limited mtDNA-induced systemic inflammation, and ameliorated burn-induced ALI. The intervening mtDNA level is thus a potential target to protect from burn-induced lung injury during aeromedical conditions and provides safer air evacuations for severely burned patients.

Significance of vascular endothelium growth factor testing in exhaled breath condensate of patients with acute respiratory distress syndrome

OBJECTIVE:

We aimed to observe and investigate the clinical significance of vascular endothelium growth factor (VEGF) levels in exhaled breath condensate (EBC) from patients with acute respiratory distress syndrome (ARDS).

METHODS:

An improved EcoScreen condenser was used to collect EBC from 31 ARDS patients on mechanical ventilation and from 22 healthy subjects. Serum and EBC VEGF levels were analyzed with ELISA. VEGF levels in the EBC of patients with different grades of lung injuries were analyzed. The correlation between VEGF levels and clinical indicators was analyzed.

RESULTS:

Serum and EBC VEGF levels were linearly and positively correlated with a correlation coefficient of 0.694 (P< 0.01). The VEGF level in the EBC of ARDS patients was significantly lower than that in the control group (P< 0.01). The VEGF level in the EBC of the mild ARDS group was higher than that in the moderate-severe ARDS group (P< 0.01). The VEGF level in the EBC of the survival group was higher than that in the mortality group. The VEGF level in the EBC of ARDS patients was positively correlated with PaO2/FiO2 and PaO2 and was negatively correlated with lung injury score (LIS) and A-aDO2/PaO2.

CONCLUSION:

The changes in VEGF levels in the EBC of ARDS patients can Respiratory Medicine, reflect the severity of lung injury. Therefore, VEGF level in EBC can be used as an auxiliary index for judging the severity and prognosis of ARDS patients.

Advances in airway management and mechanical ventilation in inhalation injury

PURPOSE OF REVIEW

Airway management, mechanical ventilation, and treatment of systemic poisoning in burn patients with inhalation injury remains challenging. This review summarizes new concepts as well as open questions.

RECENT FINDINGS

Several life-threatening complications, such as airway patency impairment and respiratory insufficiency, can arise in burn patients and require adequate and timely airway management. However, unnecessary endotracheal intubation should be avoided. Direct visual inspection via nasolaryngoscopy can guide appropriate airway management decisions. In cases of lower airway injury, bronchoscopy is recommended to remove casts and estimate the extent of the injury in intubated patients. Several mechanical ventilation strategies have been studied. An interesting modality might be high-frequency percussive ventilation. However, to date, there is no sound evidence that patients with inhalation injury should be ventilated with modes other than those applied to non-burn patients. In all burn patients exposed to enclosed fire, carbon monoxide as well as cyanide poisoning should be suspected. Carbon monoxide poisoning should be treated with an inspiratory oxygen fraction of 100%, whereas cyanide poisoning should be treated with hydroxocobalamin.

SUMMARY

Burn patients need specialized care that requires specific knowledge about airway management, mechanical ventilation, and carbon monoxide and cyanide poisoning.

Association between age and acute respiratory distress syndrome development and mortality following trauma

BACKGROUND

Improved understanding of the relationship between patient age and acute respiratory distress syndrome (ARDS) development and mortality following traumatic injury may help facilitate generation of new hypotheses about ARDS pathophysiology and the role of novel treatments to improve outcomes across the age spectrum.

METHODS

We conducted a retrospective cohort study of trauma patients included in the National Trauma Data Bank who were admitted to an intensive care unit from 2007 to 2016. We determined ARDS incidence and mortality across eight age groups for the entire 10-year study period and by year. We used generalized linear Poisson regression models adjusted for underlying mortality risk (injury mechanism, Injury Severity Score, admission Glasgow Coma Scale score, admission heart rate, and admission hypotension).

RESULTS

Acute respiratory distress syndrome occurred in 3.1% of 1,297,190 trauma encounters. Acute respiratory distress syndrome incidence was lowest among pediatric patients and highest among adults aged 35 to 64 years. Acute respiratory distress syndrome mortality was highest among patients 80 years or older (43.9%), followed by 65 to 79 years (30.6%) and 4 years or younger (25.3%). The relative risk of mortality associated with ARDS was highest among the pediatric age groups, with an adjusted relative risk (aRR) of 2.06 (95% confidence interval [CI], 1.72-2.70) among patients 4 years or younger compared with an aRR of 1.51 (95% CI, 1.42-1.62) for the entire cohort. Acute respiratory distress syndrome mortality increased over the 10-year study period (aRR, 1.03 per year; 95% CI, 1.02-1.05 per year), whereas all-cause mortality decreased (aRR, 0.98 per year; 95% CI, 0.98-0.99 per year).

CONCLUSIONS

While ARDS development following traumatic injury was most common in middle-aged adults, patients 4 years or younger and 65 years or older with ARDS experienced the highest burden of mortality. Children 4 years or younger were disproportionately affected by ARDS relative to their low underlying mortality following trauma that was not complicated by ARDS. Acute respiratory distress syndrome-associated mortality following trauma has worsened over the past decade, emphasizing the need for new prevention and treatment strategies.

LEVEL OF EVIDENCE

Prognostic/epidemiological study, level III.

Burn injury

Burn injuries are under-appreciated injuries that are associated with substantial morbidity and mortality. Burn injuries, particularly severe burns, are accompanied by an immune and inflammatory response, metabolic changes and distributive shock that can be challenging to manage and can lead to multiple organ failure. Of great importance is that the injury affects not only the physical health, but also the mental health and quality of life of the patient. Accordingly, patients with burn injury cannot be considered recovered when the wounds have healed; instead, burn injury leads to long-term profound alterations that must be addressed to optimize quality of life. Burn care providers are, therefore, faced with a plethora of challenges including acute and critical care management, long-term care and rehabilitation. The aim of this Primer is not only to give an overview and update about burn care, but also to raise awareness of the ongoing challenges and stigmata associated with burn injuries.

Is Chinese Medicine Injection Applicable for Treating Acute Lung Injury and Acute Respiratory Distress Syndrome? A Systematic Review and Meta-analysis of Randomized Controlled Trials

OBJECTIVE

To assess the efficacy and safety of Chinese medicine injection (CMI) for treating acute lung injury/acute respiratory distress syndrome (ALI/ARDS).

METHODS

Randomized controlled trials (RCTs) were identified by searching 3 English databases and 4 Chinese databases from their inceptions until February 2019. The Cochrane Handbook was used to evaluate risk of bias in the included studies. Data analysis was conducted using RevMan 5.3.3 software.

RESULTS

A total of 19 eligible RCTs involving 1,334 participants was included in this systematic review and meta-analysis. The main meta-analysis showed that CMI combined with conventional therapy (CT) was more effective than CT alone in reducing the acute physiology and chronic health evaluation (APACHE) H score [mean difference (MD): -1.74 points, 95% confidence interval (CI): -2.77 to -0.71, I²=0] and increasing the total effective rate [relative risk (RR): 1.35, 95% CI: 1.17 to 1.56, I²=37%]. Compared with CT, CMI combined with CT showed improvements in the arterial partial pressure of oxygen (PaO₂, MD: 9.25 mm Hg, 95% CI: 0.87 to 17.63, I²=98%) and oxygenation index [arterial partial pressure of oxygen (PaO₂)/fraction of inspired oxygen (FiO₂), MD: 50.75 mm Hg, 95% CI: 35.18 to 66.31, I²=94%]. CMI plus CT was superior to CT in reducing the systemic inflammatory response syndrome (SIRS) score (MD: -0.84 points, 95% CI: -1.26 to -0.42, I²=65%), length of hospital stay (MD: -4.22 days, 95% CI: -6.49 to -1.95, I²=92%), and duration of mechanical ventilation (MD: -2.94 days, 95% CI: -4.68 to -1.21, I²=89%). Only 1 study reported adverse events.

CONCLUSIONS

CMI as an adjuvant therapy showed great potential benefits for the treatment of ALI/ARDS. However, we could not make a definite conclusion due to low quality of included studies and uncertain security. Future studies should focus on improving research design, especially in blindness and placebo. The reporting of adverse events was also needed.

Extracorporeal membrane oxygenation for acute respiratory distress syndrome in burn patients: a case series and literature update

Background

Acute respiratory distress syndrome (ARDS) has a reported incidence of 34–43% in ventilated burn patients and is associated with a mortality of 59% in the severe form. The use and experience with extracorporeal membrane oxygenation (ECMO) in burn patients developing ARDS are still limited. We present our results and discuss the significance of ECMO in treating burn patients.

Methods

A retrospective analysis of burn patients treated with ECMO for ARDS between January 2017 and January 2019 was performed. Demographic, clinical, and outcome data were collected and analyzed.

Results

Eight burn patients were treated at our institution with ECMO in the designated time period. Of these, all but one patient had inhalation injury, burn percentage of TBSA was 37 ± 23%, ABSI score was 8.4 ± 2, and R-Baux-score was 98 ± 21. Seven patients developed severe ARDS and one patient moderate ARDS according to the Berlin classification with a PaO₂/FiO₂ ratio upon initiation of ECMO therapy of 62 ± 22 mmHg. ECMO duration was 388 ± 283 h. Three patients died from severe sepsis while five patients survived to hospital discharge.

Conclusions

ECMO is a viable therapy option in burn patients developing severe ARDS and can contribute to survival rates similar to ECMO therapy in non-burn-associated severe ARDS. Consequently, patients with severe respiratory insufficiency with unsuccessful conventional treatment and suspected worsening should be transferred to burn units with the possibility of ECMO treatment to improve outcome.

Automatic proximal airway volume segmentation using optical coherence tomography for assessment of inhalation injury

BACKGROUND

Acute respiratory distress syndrome (ARDS) is a severe form of acute lung injury with a mortality rate of up to 40%. Early management of ARDS has been difficult due to the lack of sensitive imaging tools and robust analysis software. We previously designed an optical coherence tomography (OCT) system to evaluate mucosa thickness (MT) after smoke inhalation, but the analysis relied on manual segmentation. The aim of this study is to assess in vivo proximal airway volume (PAV) after inhalation injury using automated OCT segmentation and correlate the PAV to lung function for rapid indication of ARDS.

METHODS

Anesthetized female Yorkshire pigs (n = 14) received smoke inhalation injury (SII) and 40% total body surface area thermal burns. Measurements of PaO2-to-FiO2 ratio (PFR), peak inspiratory pressure (PIP), dynamic compliance, airway resistance, and OCT bronchoscopy were performed at baseline, postinjury, 24 hours, 48 hours, 72 hours after injury. A tissue segmentation algorithm based on graph theory was used to reconstruct a three-dimensional (3D) model of lower respiratory tract and estimate PAV. Proximal airway volume was correlated with PFR, PIP, compliance, resistance, and MT measurement using a linear regression model.

RESULTS

Proximal airway volume decreased after the SII: the group mean of proximal airway volume at baseline, postinjury, 24 hours, 48 hours, 72 hours were 20.86 cm (±1.39 cm), 17.61 cm (±0.99 cm), 14.83 cm (±1.20 cm), 14.88 cm (±1.21 cm), and 13.11 cm (±1.59 cm), respectively. The decrease in the PAV was more prominent in the animals that developed ARDS after 24 hours after the injury. PAV was significantly correlated with PIP (r = 0.48, p < 0.001), compliance (r = 0.55, p < 0.001), resistance (r = 0.35, p < 0.01), MT (r = 0.60, p < 0.001), and PFR (r = 0.34, p < 0.01).

CONCLUSION

Optical coherence tomography is a useful tool to quantify changes in MT and PAV after SII and burns, which can be used as predictors of developing ARDS at an early stage.

LEVEL OF EVIDENCE

Prognostic, level III.

Changes in ventilator settings and ventilation-induced lung injury in burn patients-A systematic review

OBJECTIVE

Ventilation strategies aiming at prevention of ventilator-induced lung injury (VILI), including low tidal volumes (V_T) and use of positive end-expiratory pressures (PEEP) are increasingly used in critically ill patients. It is uncertain whether ventilation practices changed in a similar way in burn patients. Our objective was to describe applied ventilator settings and their relation to development of VILI in burn patients.

DATA SOURCES

Systematic search of the literature in PubMed and EMBASE using MeSH, EMTREE terms and keywords referring to burn or inhalation injury and mechanical ventilation.

STUDY SELECTION

Studies reporting ventilator settings in adult or pediatric burn or inhalation injury patients receiving mechanical ventilation during the ICU stay.

DATA EXTRACTION

Two authors independently screened abstracts of identified studies for eligibility and performed data extraction.

DATA SYNTHESIS

The search identified 35 eligible studies. V_T declined from 14 ml/kg in studies performed before to around 8 ml/kg predicted body weight in studies performed after 2006. Low-PEEP levels (<10 cmH₂O) were reported in 70% of studies, with no changes over time. Peak inspiratory pressure (PIP) values above 35 cmH₂O were frequently reported. Nevertheless, 75% of the studies conducted in the last decade used limited maximum airway pressures (≤35 cmH₂O) compared to 45% of studies conducted prior to 2006. Occurrence of barotrauma, reported in 45% of the studies, ranged from 0 to 29%, and was more frequent in patients ventilated with higher compared to lower airway pressures.

CONCLUSION

This systematic review shows noticeable trends of ventilatory management in burn patients that mirrors those in critically ill non-burn patients. Variability in available ventilator data precluded us from drawing firm conclusions on the association between ventilator settings and the occurrence of VILI in burn patients.

The Use of Extracorporeal Membrane Oxygenation for Acute Respiratory Distress Syndrome in Severe Burns Without Inhalation Injury

Burn injury results in a severe systemic inflammatory response which is associated with the development of acute respiratory distress syndrome (ARDS), even without associated inhalation injury. Venous-venous extracorporeal membrane oxygenation (VV-ECMO) has been implemented in various cases of ARDS to provide support and allow for protective lung ventilation strategies. We report the case of a 27-year-old man presenting with a 60% total body surface area partial thickness burn who developed refractory ARDS with Murray Score of 3.75. ECMO was initiated on hospital day 9 for a total of 10 days with concurrent lung-protective ventilation. He subsequently recovered and was discharged on hospital day 48. ECMO should be considered as an adjunctive strategy in burn patients without inhalation injury to minimize ventilator-induced lung injury when high levels of support are needed to achieve adequate ventilation in patients with ARDS.

The abbreviated burn severity index as a predictor of acute respiratory distress syndrome in young individuals with severe flammable starch-based powder burn

Here, we investigated whether the abbreviated burn severity index (ABSI) scoring system predicts acute respiratory distress syndrome (ARDS) in a retrospective analysis of a severe flammable starch-based powder burn population. Demographics, total body surface area (TBSA) burn, the presence of mouth and nose burn, ABSI, inhalation injury, and clinical outcomes for each patient were analysed for association with inpatient ARDS based on the Berlin definition. We treated 53 patients (64% male, 36% female) and observed no fatalities. The median age, TBSA burn, and the ABSI were 22.2±3.6, 42.2±21, and 7.8±2.8, respectively. Inhalation injury was present in 56.6% of the cases, and mouth and nose burn was present in 30.2%. ARDS was prevalent at 30%. The mean abbreviated burn severity index (ABSI) was 10.6±1.5 in the ARDS group and 6.6±2.3 in the non-ARDS (P<0.001) group. The mean TBSA burn percentage for ARDS and the non-ARDS groups were 61.4±13.9% and 34±18%, respectively (P<0.001). The area under the curve of the receiver operating characteristic curves for an ABSI≥9 was 0.905. Our results show that the ABSI is effective for predicting ARDS in young individuals with severe starch-based powder burn.

Correlation Between PaO2/FIO2 and Peripheral Capillary Oxygenation/FIO2 in Burned Children With Smoke Inhalation Injury

OBJECTIVES

Determine whether the peripheral capillary oxygenation/FIO2 ratio correlates with the PaO2/FIO2 ratio in burned children with smoke inhalation injury, with the goal of understanding if the peripheral capillary oxygenation/FIO2 ratio can serve as a surrogate for the PaO2/FIO2 ratio for the diagnosis of acute respiratory distress syndrome.

DESIGN

Retrospective chart review.

SETTING

Shriners Hospitals for Children-Galveston.

PATIENTS

All burned children with smoke inhalation injury who were admitted from 1996 to 2014 and had simultaneously obtained peripheral capillary oxygenation, FIO2 and PaO2 measurements.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Two hundred seventy-three patients (63% male, 8 ± 5 yr, 53% ± 24% total body surface area burns) were analyzed. Peripheral capillary oxygenation/FIO2 ratios were divided into four subgroups based on peripheral capillary oxygenation values (≤ 100%, ≤ 98%, ≤ 95%, and ≤ 92%). Significance was accepted at r greater than 0.81. The r (number of matches) was 0.66 (23,072) for less than or equal to 100%, 0.87 (18,932) for less than or equal to 98%, 0.89 (7,056) for less than or equal to 95%, and 0.93 (4,229) for less than or equal to 92%. In the subgroup of patients who developed acute respiratory distress syndrome, r was 0.65 (8,357) for less than or equal to 100%, 0.89 (7,578) for less than or equal to 98%, 0.89 (4,115) for less than or equal to 95%, and 0.91 (2,288) less than or equal to 92%.

CONCLUSIONS

PaO2/FIO2 and peripheral capillary oxygenation/FIO2 strongly correlate in burned children with smoke inhalation injury, with a peripheral capillary oxygenation of less than 92% providing the strongest correlation. Thus, peripheral capillary oxygenation/FIO2 ratio may be able to serve as surrogate for PaO2/FIO2, especially when titrating FIO2 to achieve a peripheral capillary oxygenation of 90-95% (i.e., in the acute respiratory distress syndrome range).

Hypertension after injury among burned combat veterans: A retrospective cohort study

BACKGROUND

The long-term health effects of burn are poorly understood. We sought to evaluate the relationship between burn and the subsequent development of hypertension.

METHODS

Retrospective cohort study of patients admitted to our burn center from 2003 to 2010. Data collected included demographic variables, burn size, injury severity score, presence of inhalation injury, serum creatinine, need for renal replacement therapy, as well as days spent in the hospital, in the intensive care unit and on mechanical ventilation. Data for the subsequent diagnosis of hypertension was obtained from medical records. Cox proportional hazard regression models were performed to determine what factors were associated with hypertension.

RESULTS

Of the 711 patients identified, 670 were included for analysis after exclusions. After adjustment, only age (HR 1.06 per one year increase, 95% confidence interval 1.03-1.08; p<0.001), percentage of total body surface area burned (HR 1.11 per 5% increase, 95% confidence interval 1.04-1.19; p=0.002) and acute kidney injury (HR 1.68, 95% confidence interval 1.05-2.69; p=0.03) were associated with hypertension.

CONCLUSION

Burn size is independently associated with the subsequent risk of hypertension in combat casualties. Clinical support for primary prevention techniques to reduce the incidence of hypertension specific to burn patients may be warranted.