Sepsis in the burn patient: a different problem than sepsis in the general population

Usefulness of mid-regional proadrenomedullin levels in the resuscitation phase of severely burned patients and its utility in early sepsis detection

INTRODUCTION

Mid-regional proadrenomedullin (MR-proADM) reflects the adrenomedullin level, which has vasodilatory activity, decreases endothelial permeability, and downregulates proinflammatory cytokines. Sepsis diagnosis in these patients is difficult, and MR-proADM is a widely studied sepsis biomarker. This study evaluates MR-proADM levels during the resuscitation phase, considering the potential influence of haemodynamic changes and its usefulness for the early sepsis detection in burn patients.

METHODS

A prospective observational study performed in the Critical Burn Unit. Demographic data, burn characteristics, comorbidities, prognostic/severity scales, and haemodynamic parameters were collected. The resuscitation protocol guided by diuresis, transpulmonary thermodilution, and lactate levels was followed. Blood samples were collected at various time points for biomarker measurement. Biomarker levels, including MR-proADM, C-reactive protein, and procalcitonin were measured during the resuscitation phase and septic episodes.

RESULTS

Twenty-seven patients were included, with a mean age of 51 years, a mean total body surface area burn of 41.8%, a mean Abbreviated Burn Severity Index of 9.7, and a mean Baux score of 92. MR-proADM levels were elevated on admission (0.9 ± 0.5 nmol/l) and continued to increase slightly during the resuscitation phase (2.4 ± 2.2 nmol/l). Haemodynamic changes during resuscitation did not significantly affect MR-proADM levels. Twelve of the 27 patients developed sepsis, whose MR-proADM levels were significantly elevated on the day of clinical diagnosis (3.91 ± 2.99 nmol/l) and even the day before (2.57 ± 3.37). Higher MR-proADM levels were associated with greater severity as measured by the Sequential Organ Failure Assessment score. The mean MR-proadrenomedullin values during resuscitation in the patients who died was 3.51 ± 2.30 nmol/l, whereas in the survivors it was 1.28 ± 1.10 nmol/l (p = 0.0001).

CONCLUSION

MR-proadrenomedullin values are elevated after thermal injury but are not affected by haemodynamic changes. During septic episodes in burn patients, MR-proADM rises early (the day before sepsis diagnosis). Higher levels of MR-proADM are associated with greater organ dysfunction and mortality.

Sepsis in surgical patients: Burn sepsis

Patients with large burn injuries remain a challenge. The loss of skin barrier integrity and induced immunosuppression after injury increases their vulnerability to infection. Sepsis remains the primary cause of death for burn-injured patients who survive their acute injury and resuscitation. The objective of this work is to describe the current understanding and management of sepsis in the burn-injured patient and newer strategies to approach its management. Current understanding of the systemic inflammatory response to burn injury and sepsis, preventative strategies, and novel research will be discussed. Understanding the origin of burn sepsis from wounds themselves is key to understanding current paradigms. Infection control and management begins from the time of injury and continues throughout the patient's hospital course. The use of personal protective equipment, burn unit design considerations, and optimization of prevention protocols and catheter care all play a role in burn sepsis prevention and management. The emergence of drug-resistant pathogens poses a particular challenge for burn patients due to the chronicity with which their wounds are sometimes open. The difficulty of systemic antibiotics to reach wounds has underscored the need to anticipate resistant organisms moving forward. Antibiotic strategies and newer approaches, such as phage therapy, will be discussed. Multi-omics approaches to understanding burn sepsis have developed in hopes of identifying patients more susceptible or at risk of developing burn sepsis. As with many aspects of burn care, a multidisciplinary, proactive approach to the management of burn sepsis is key to minimizing the morbidity and mortality associated with this complication.

Prevention and Management of Wound Infections in Burn Patients

The leading cause of morbidity in burn patients is infection with pneumonia, urinary tract infection, cellulitis, and wound infection being the most common cause. High mortality is due to the immunocompromised status of patients and abundance of multidrug-resistant organisms in burn units. Despite the criteria set forth by American Association of Burn, the diagnosis and treatment of burn infections are not always straightforward. Topical antimicrobials, isolation, hygiene, and personal protective equipment are common preventive measures. Additionally medical and nutritional optimization of the patients is crucial to reverse the immunocompromised status triggered by burn injury.

Differentiated expressed miRNAs in splenic monocyte induced by burn injury in mice

To find potential biomarkers based on miRNA and their potential targets in splenic monocytes in burn-injured mice. Male Balb/c mice were subjected to sham or scalding injury of 15% total body surface area. Spenic CD11b+ monocytes were purified with magnetic beads. The monocytes were cultured in the presence of lipopolysaccharide. The proliferation of monocytes was detected by MTT assay, and the cytokines in the supernatant were examined by enzyme linked immunosorbent assay. The purified monocytes were also under total RNA extraction. The differential monocytic miRNAs expression between the sham and burn-injured mice was analysed by miRNA microarray. The activity of monocytes was comparable between the two groups (p > 0.05). However, monocytes from burn-injured mice secreted higher levels of tumour necrosis factor (TNF)-α and transforming growth factor-β, but lower level of monocyte chemoattratctant protein-1. A total of 54 miRNAs were differentially expressed in monocytes from burn relative to sham-injured mice (fold >3). Further quantitative reverse transcription polymerase chain reaction confirmed that the expression of miR-146a was significantly down-regulated, while miR-3091-6p was up-regulated after burn injury. Using the combination of Miranda and TargetScan softwares, we found that mir-146a may regulate 180 potential target genes including TNF receptor related factor 6 (TRAF6), interleukin-1 receptor related kinase 1 (IRAK1) and CD28. Mir-3091-6p may regulate 39 potential targets, including SOCS7 (cytokine signal transduction inhibitor 7) and ARRB2 (arrestin, β 2). The miRNAs expressed by monocytes after burn injury may be involved in the regulation of innate immune response in burn injury.

An Overview of Recent Developments in the Management of Burn Injuries

According to the World Health Organization (WHO), around 11 million people suffer from burns every year, and 180,000 die from them. A burn is a condition in which heat, chemical substances, an electrical current or other factors cause tissue damage. Burns mainly affect the skin, but can also affect deeper tissues such as bones or muscles. When burned, the skin loses its main functions, such as protection from the external environment, pathogens, evaporation and heat loss. Depending on the stage of the burn, the patient's condition and the cause of the burn, we need to choose the most appropriate treatment. Personalization and multidisciplinary collaboration are key to the successful management of burn patients. In this comprehensive review, we have collected and discussed the available treatment options, focusing on recent advances in topical treatments, wound cleansing, dressings, skin grafting, nutrition, pain and scar tissue management.

Surviving Sepsis After Burn Campaign

INTRODUCTION

The Surviving Sepsis Campaign was developed to improve outcomes for all patients with sepsis. Despite sepsis being the primary cause of death after thermal injury, burns have always been excluded from the Surviving Sepsis efforts. To improve sepsis outcomes in burn patients, an international group of burn experts developed the Surviving Sepsis After Burn Campaign (SSABC) as a testable guideline to improve burn sepsis outcomes.

METHODS

The International Society for Burn Injuries (ISBI) reached out to regional or national burn organizations to recommend members to participate in the program. Two members of the ISBI developed specific "patient/population, intervention, comparison and outcome" (PICO) questions that paralleled the 2021 Surviving Sepsis Campaign [1]. SSABC participants were asked to search the current literature and rate its quality for each topic. At the Congress of the ISBI, in Guadalajara, Mexico, August 28, 2022, a majority of the participants met to create "statements" based on the literature. The "summary statements" were then sent to all members for comment with the hope of developing an 80% consensus. After four reviews, a consensus statement for each topic was created or "no consensus" was reported.

RESULTS

The committee developed sixty statements within fourteen topics that provide guidance for the early treatment of sepsis in burn patients. These statements should be used to improve the care of sepsis in burn patients. The statements should not be considered as "static" comments but should rather be used as guidelines for future testing of the best treatments for sepsis in burn patients. They should be updated on a regular basis.

CONCLUSION

Members of the burn community from the around the world have developed the Surviving Sepsis After Burn Campaign guidelines with the goal of improving the outcome of sepsis in burn patients.

Temperature Derangement on Admission is Associated With Mortality in Burn Patients-A Nationwide Analysis and Opportunity for Improvement

Although single-institution studies have described the relationship between hypothermia, burn severity, and complications, there are no national estimates on how temperature on admission impacts hospital mortality. This study aims to evaluate the relationship between admission temperature and complications on a national scale to expose opportunities for improved outcomes. The US National Trauma Data Bank (NTDB) was analyzed between 2007 and 2018. Mortality was modeled using multivariable logistic regression including burn severity variables (% total burn surface area (TBSA), inhalation injury, emergency department (ED) temperature), demographics, and facility variables. Temperature was parsed into three categories: hypothermia (<36.0°C), euthermia (36.0-37.9°C), and hyperthermia (≥38.0°C). A total of 116,796 burn encounters were included of which 77.9% were euthermic, 20.6% were hypothermic and 1.45% were hyperthermic on admission. For every 1.0C drop in body temperature from 36.0°C, mortality increased by 5%. Both hypothermia and hyperthermia were independently associated with increased odds of mortality when controlling for age, gender, inhalation injury, number of comorbidities, and %TBSA burned (p < .001). All temperatures below 36.0°C were significantly associated with increased odds of mortality. Patients with ED temperatures between 32.5 and 33.5°C had the highest odds of mortality (22.0, 95% CI 15.6-31.0, p < .001). ED hypothermia and hyperthermia are independently associated with mortality even when controlling for known covariates associated with inpatient death. These findings underscore the importance of early warming interventions both at the prehospital stage and upon ED arrival. ED temperature could become a quality metric in benchmarking burn centers to improve mortality.

Critical Care of the Burn Patient

Care of the critically ill burned patient must integrate a multidisciplinary care team composed of burn care specialists. As resuscitative mortality decreases more patients are surviving to experience multisystem organ failure relating to complications of their injuries. Clinicians must be aware of physiologic changes following burn injury and the implicated impacts on management strategy. Promoting wound closure and rehabilitation should be the backdrop for which management decisions are made.

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.

Infections in Burn Patients

Infections are the leading cause of mortality in burn patients who survive their initial resuscitation. Burn injury leads to immunosuppression and a dysregulated inflammatory response which can have a prolonged impact. Early surgical excision along with support of the multidisciplinary burn team has improved mortality in burn patients. The authors review diagnostic and therapeutic challenges as well as strategies for management of burn related infections.

LncRNA GAS5 suppresses inflammatory responses by inhibiting HMGB1 release via miR-155-5p/SIRT1 axis in sepsis

Sepsis comprises a lethal immunologic response due to infection. Increasingly, evidence has demonstrated the important role of long non-coding RNA growth arrest-specific transcript 5 (GAS5) in the regulation of sepsis. Nevertheless, the mechanisms by which GAS5 participates in the progression of sepsis remain unclear. Our study demonstrated the role and underlying mechanism of GAS5 in regulating lipopolysaccharide (LPS)-induced inflammation. In this study, GAS5 expression was found to be markedly decreased in serum samples of sepsis patients and a sepsis mouse model, and was negatively related with HMGB1 expression. GAS5 overexpression inhibited cell inflammatory responses by decreasing HMGB1 release. Furthermore, GAS5 inhibited LPS-mediated hyperacetylation and the release of HMGB1 by increasing the expression of sirtuin1 (SIRT1). Additionally, upregulated GAS5 attenuated inflammatory responses in vitro and vivo, and the knockdown of a miR-155-5p mimic and SIRT1 rescued the effects of GAS5 upregulation. Mechanistically, GAS5 sponged miR-155-5p to upregulate SIRT1, thereby inhibiting HMGB1 acetylation and release. In conclusion, our findings indicate that GAS5 suppresses inflammatory responses by modulating the miR-155-5p/SIRT1/HMGB1 axis in sepsis, providing a novel therapeutic target for inflammation in sepsis.

Use of procalcitonin as a biomarker for sepsis in pediatric burns

Infection and sepsis continue to be the leading cause of morbidity and death in burn injuries. Diagnosing sepsis in burns is challenging as signs and symptoms of sepsis are not specific and overlap with those related to the burn injury. While the use of procalcitonin (PCT) as a biomarker is recommended for diagnosing sepsis in burns, evidence for children with burns is scarce. In this study, we aimed to investigate the role of PCT in distinguishing sepsis in pediatric burns. A prospective observational study was conducted in a single pediatric burn unit. Children hospitalized with burns ≤ 30% of total body surface area were included while patients with chemical burn, inhalation injury, or concomitant chronic diseases were excluded. Patients were classified into three groups for sepsis, systemic inflammatory response syndrome (SIRS), or controls using the American Burn Association (ABA) criteria. The predictive role of C-reactive protein (CRP) and PCT was investigated for distinguishing sepsis. Seventy-two patients were included in the study. The median total body surface area (TBSA) size was 12% (2.0-28.5%), and the median abbreviated burn severity index (ABSI) score was 3 (2-7). The median length of burn unit stay was 9.5 days (1-59 days). Sepsis was diagnosed in 11 patients (15.2%), and SIRS was present in 23 patients (40.0%), whereas 38 patients (52.8%) had neither SIRS nor sepsis (control group). Receiver operating characteristic analysis revealed that CRP and PCT levels distinguished sepsis patients from non-sepsis patients while PCT had a higher positive predictive value (50.0% vs. 45.0%). Optimal cutoff values of CRP and PCT for distinguishing sepsis were 66.75 mg/L and 0.95 ng/mL.

CONCLUSIONS

PCT levels could distinguish sepsis in children with burn injuries, performing better than CRP levels. Confirmatory studies are needed to evaluate the development of sepsis and the role of PCT in diagnosing sepsis in pediatric burn patients.

WHAT IS KNOWN

• Even though there are excellent criteria for the diagnosis of infection and sepsis in children and several clinical parameters and biomarkers are being studied, it's difficult to diagnose burn wound sepsis in children.

WHAT IS NEW

• Data from this study showed that procalcitonin levels performed better than CRP levels as a biomarker for distinguishing sepsis from systemic inflammatory response syndrome (SIRS) in children with burn injuries.

Prospective study and validation of early warning marker discovery based on integrating multi-omics analysis in severe burn patients with sepsis

Background

Early detection, timely diagnosis and rapid response are essential for case management and precautions of burn-associated sepsis. However, studies on indicators for early warning and intervention have rarely been conducted. This study was performed to better understand the pathophysiological changes and targets for prevention of severe burn injuries.

Methods

We conducted a multi-center, prospective multi-omics study, including genomics, microRNAomics, proteomics and single-cell transcriptomics, in 60 patients with severe burn injuries. A mouse model of severe burn injuries was also constructed to verify the early warning ability and therapeutic effects of potential markers.

Results

Through genomic analysis, we identified seven important susceptibility genes (DNAH11, LAMA2, ABCA2, ZFAND4, CEP290, MUC20 and ENTPD1) in patients with severe burn injuries complicated with sepsis. Through plasma miRNAomics studies, we identified four miRNAs (hsa-miR-16-5p, hsa-miR-185-5p, hsa-miR-451a and hsa-miR-423-5p) that may serve as early warning markers of burn-associated sepsis. A proteomic study indicated the changes in abundance of major proteins at different time points after severe burn injury and revealed the candidate early warning markers S100A8 and SERPINA10. In addition, the proteomic analysis indicated that neutrophils play an important role in the pathogenesis of severe burn injuries, as also supported by findings from single-cell transcriptome sequencing of neutrophils. Through further studies on severely burned mice, we determined that S100A8 is also a potential early therapeutic target for severe burn injuries, beyond being an early warning indicator.

Conclusions

Our multi-omics study identified seven susceptibility genes, four miRNAs and two proteins as early warning markers for severe burn-associated sepsis. In severe burn-associated sepsis, the protein S100A8 has both warning and therapeutic effects.

Glutamine promotes O-GlcNAcylation of G6PD and inhibits AGR2 S-glutathionylation to maintain the intestinal mucus barrier in burned septic mice

Mucus forms the first line of defence of the intestinal mucosa barrier, and mucin is its core component. Glutamine is a vital energy substance for goblet cells; it can promote mucus synthesis and alleviate damage to the intestinal mucus barrier after burn injury, but its mechanism is not fully understood. This study focused on the molecular mechanisms underlying the effects of glutamine on the synthesis and modification of mucin 2 (MUC2) by using animal and cellular models of burn sepsis. We found that anterior gradient-2 (AGR2) plays a key role in the posttranslational modification of MUC2. Oxidative stress induced by burn sepsis enhanced the S-glutathionylation of AGR2, interfered with the processing and modification of MUC2 precursors by AGR2 and blocked the synthesis of mature MUC2. Further studies revealed that NADPH, catalysed by glucose-6-phosphate dehydrogenase (G6PD), is a key molecule in inhibiting oxidative stress and regulating AGR2 activity. Glutamine promotes O-linked N-acetylglucosamine (O-GlcNAc) modification of G6PD via the hexosamine pathway, which facilitates G6PD homodimer formation and increases NADPH synthesis, thereby inhibiting AGR2 S-glutathionylation and promoting MUC2 maturation, ultimately reducing damage to the intestinal mucus barrier after burn sepsis. Overall, we have demonstrated that the central mechanisms of glutamine in promoting MUC2 maturation and maintaining the intestinal mucus barrier are the enhancement of G6PD glycosylation and inhibition of AGR2 S-glutathionylation.

Effects of enteral nutrition with different energy supplies on metabolic changes and organ damage in burned rats

BACKGROUND

Enteral nutrition (EN) is an important treatment for burn patients. However, severe gastrointestinal damage caused by major burns often leads to EN intolerance. Trophic EN solves this problem basically, but how to transition from trophic EN to standard EN smoothly is still a challenge in burn clinical nutrition. The aim of this study is to investigate the effects of EN with different energy supplies on metabolic changes, organ damage and prognosis in burned rats.

METHODS

Different feeding regimens were designed based on the continuous monitoring of resting energy expenditure in rats. Thirty-two Sprague-Dawley rats were randomly divided into a normal control group, burn +50% REE group, burn +75% REE group and burn +100% REE group. At the end of a nutritional treatment cycle (14th day), nuclear magnetic resonance spectroscopy, blood biochemistry analysis and quantification of subscab bacteria were performed to explore the differences in metabolic changes, degrees of organ damage and prognoses between the groups.

RESULTS

Sixteen metabolites involving seven metabolic pathways were identified from the different energy supply groups. After burn injury, resting energy consumption and body weight loss increased obviously. Meanwhile, weight loss was inversely related to energy supply. The greatest changes in the degree of organ damage, the level of plasma proteins, lipids and endotoxins, as well as the quantification of subscab bacteria were observed in the 50% REE group, followed by the 75 and 100% groups.

CONCLUSIONS

Achieving an early balance between energy supply and expenditure is conducive to mitigating metabolic disorders and improving prognosis after burn injury.

Interferon gamma as an immune modulating adjunct therapy for invasive mucormycosis after severe burn – A case report

Background

Mucormycosis is a deadly fungal infection that mainly affects severely immunocompromised patients. We report herein the case of a previously immunocompetent adult woman who developed invasive cutaneous mucormycosis after severe burn injuries. Interferon-gamma (IFN-γ) treatment was added after failure of conventional treatment and confirmation of a sustained profound immunodepression. The diagnosis was based on a reduced expression of HLA-DR on monocytes (mHLA-DR), NK lymphopenia and a high proportion of immature neutrophils. The immune-related alterations were longitudinally monitored using panels of immune-related biomarkers.

Results

Initiation of IFN-γ was associated with a rapid clinical improvement and a subsequent healing of mucormycosis infection, with no residual fungi at the surgical wound repair. The serial immunological assessment showed sharp improvements of immune parameters: a rapid recovery of mHLA-DR and of transcriptomic markers for T-cell proliferation. The patient survived and was later discharged from the ICU.

Conclusion

The treatment with recombinant IFN-γ participated to the resolution of a progressively invasive mucormycosis infection, with rapid improvement in immune parameters. In the era of precision medicine in the ICU, availability of comprehensive immune monitoring tools could help guiding management of refractory infections and provide rationale for immune stimulation strategies in these high risk patients.

Human skin processing affects clinical outcome in allograft recipients

Skin allografts represent a milestone in burn patient treatment. However, skin procurement is still burdened by high rates of contamination, and validation procedures have not yet been standardized. In addition, it is not clear if tissue viability affects allograft skin outcomes. In 2120 skin samples from 610 donors, a retrospective analysis was performed to identify donor and procurement variables associated with bacterial contamination and tissue viability. Post-processing contamination was associated significantly with the donor type, cause of death, length of hospitalization, procurement site, surgeon, interval between procurement and banking, and decontamination method. Tissue viability appeared to be negatively associated with freezing. In two series of skin allograft recipients (155 and 195 patients), we evaluated the role of skin characteristics and procurement variables on clinical outcomes. We found that the length of hospitalization was associated significantly with donor age. Procalcitonin and PCR values in allograft recipients were correlated with the decontamination method. No significant associations were observed between tissue viability and clinical outcomes (length of hospitalization, cause of donor death, or inflammatory parameters) after allograft transplantation. In these large case series, we identified donor and procurement variables that may affect allograft skin recipients. The decontamination method appeared to be a critical step for skin allograft requiring better standardization.

Emergence of a Carbapenem-Resistant Klebsiella pneumoniae Isolate Co-harbouring Dual bla NDM- 6 -Carrying Plasmids in China

The widespread emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) with limited therapeutic options has become a global concern. In this study, a K. pneumoniae strain called KP2e was recovered from a human case of fatal septic shock in a Chinese hospital. Polymerase chain reaction and sequencing, antimicrobial susceptibility testing, conjugation experiments, S1 nuclease-pulsed field gel electrophoresis/southern blot, whole genome sequencing and comparative genomics were performed to investigate the phenotypic and molecular characteristics of this isolate. KP2e possessed the NDM-6-encoding gene and exhibited resistance to almost all β-lactams except for monobactam. This strain belonged to sequence type 4024, the complete genome of which was composed of one chromosome and three plasmids. Furthermore, bla_NDM–6 coexisted on two self-transmissible plasmids, which were assigned to types IncFIB and IncN. A structure of IS26-composite transposon capturing an identical Tn125 remnant (ΔISAba125-bla_NDM–6-ble_MBL-trpF-dsbC-cutA-groES-ΔgroEL) was identified in the two plasmids, and this conserved bla_NDM-surrounding genetic context was similar to that of few IncN plasmids found in other regions of China. Our research appears to be the first description of a clinical strain that emerged co-harbouring dual bla_NDM-carrying plasmids, and the first report of NDM-6-positive CRKP in China. These findings demonstrated that IncN is a key medium in the evolution and expanding dissemination of bla_NDM genes among various species, which indicates that close monitoring and rapid detection of bla_NDM-harbouring plasmids is necessary.

Modern Aspects of Burn Injury Immunopathogenesis and Prognostic Immunobiochemical Markers (Mini-Review)

Burn injuries are among the most common peacetime injuries, with mortality ranging from 2.3% to 3.6%. At the same time, 85–90% of patients with burns are people of working age and children. Burn injury leads to metabolic disorders and systemic inflammatory response, inefficient energy consumption, and other physiological changes that can lead to dysfunction of organs and systems. The most formidable complication of burn injuries is sepsis mediated by multiple organ failure, the most common cause of poor prognosis in patients and has specific differences in these injuries. The purpose of this article was to dwell in detail on the most promising immunobiochemical markers of sepsis in the format of a mini-review, based on the main aspects of the immunopathogenesis of this complication. The pathogenesis of a burn injury and any general pathological process is based on an inflammatory reaction and large-scale changes in the skin and mucous membranes. This review is devoted to the progress in understanding the main aspects of the immunopathogenesis of burn lesions and the features of post-burn immune dysfunction, manifested by disorders in the innate and adaptive immunity systems. Attention is focused on the role in the immunopathogenesis of the development of systemic and local disorders in burn injury. Characterization of primary immunobiochemical markers of burn injury (cytokines, growth factors, C-reactive protein, procalcitonin, presepsin, matrix metalloproteinases, reactive oxygen species, nitric oxide, hemostasis parameters) is presented. The problem of treating burn lesions is associated with constant monitoring of the condition of patients and regular monitoring of specific immunobiochemical markers predicting sepsis for the timely initiation of a specific therapy.

Amputations secondary to burn injuries in a resource-limited setting

INTRODUCTION

Amputations are a devastating consequence of severe burns. Amputations in a resource-limited setting are challenging as rehabilitation services available to these patients are inconsistent and often fragmented. Epileptic patients are a particularly vulnerable group when it comes to burn-injuries and often sustain deeper burns. The aim of this study is to analyse amputations secondary to burn injuries. We seek to identify vulnerable groups as a means for advocacy efforts to reduce the devastation of an amputation secondary to a burn injury. This paper highlights the burden of these injuries on the healthcare system and emphasizes the need for additional trained therapists for the rehabilitation of these patients.

METHODS

A retrospective database review was conducted. All burns admissions who underwent an amputation between 1 February 2016 and 31 January 2019 were considered.

RESULTS

A total of 1575 patients were admitted during the study period. Fifty-four percent of the admissions were paediatric patients. The amputation rate in the paediatric population was 1.5% (13/850) while in the adult population it was 4.8% (35/724) . Most paediatric amputations were as a result of electrical injuries. Flame burns were most likely to result in amputations in the adult group and convulsions were the leading circumstance leading to the injury. There was no significant difference in sepsis or length of stay between the groups. There were no mortalities in the paediatric group but there was an 11% mortality rate in the adult group.

CONCLUSION

The incidence of amputations in burns is low, however, it remains a devastating morbidity. Epileptics are a vulnerable group and these patients account for the most amputations among adult burns patients. Education interventions are needed regarding their diagnosis, administration of their medication and the importance of compliance. Advocacy efforts to ensure constant supply of anti-epileptic drugs at the clinics and other district level health facilities is also essential. Electrical injuries in children are not as common as hot water scalds, however, they are more likely to result in amputation. Communities need to be informed of the risk associated with illegal electrical connections and initiatives need to drive the safe provision of affordable electricity to these under-privileged, vulnerable communities.

The Role of the Immune System in Pediatric Burns: A Systematic Review

Burns are one of the most common causes of home injuries, characterized by serious damage to the skin and causing the death of affected tissues. In this review, we intended to collect information on the pathophysiological effects of burns in pediatric patients, with particular emphasis on local and systemic responses. A total of 92 articles were included in the review, and the time range of the searched articles was from 2000 to 2021. The occurrence of thermal injuries is a problem that requires special attention in pediatric patients who are still developing. Their exposure to various burns may cause disturbances in the immune response, not only in the area of tissue damage itself but also by disrupting the systemic immune response. The aspect of immunological mechanisms in burns requires further research, and in particular, it is important to focus on younger patients as the existence of subtle differences in wound healing between adults and children may significantly influence the treatment of pediatric patients.

The effect of NPWT in wound healing and bacterial count on deep dermal burn injury model: An experimental study

Background

Sepsis is one of the main causes in burn victim's mortality. The use of negative pressure wound therapy (NPWT) provides an ideal environment to accelerate wound healing. We compare the use of normal saline (NS), intermittent NPWT, continuous NPWT and silver sulfadiazine in wound healing process.

Method

This study involved 6 Yorkshire pigs; each pig was induced with 20 burns on the flank area. Burns were divided into 4 treatment groups: NS gauze, intermittent NPWT, continuous NPWT, and silver sulfadiazine dressing. Burns were evaluated on day 1,3,7,14, and 21 for its morphology and bacterial colonization and on day 14 and 21 for the remaining burn surface area.

Result

Wound that received NPWT therapy appeared better in both granulation and crust formation. Remaining burn surface area (mm²) on day 14 in NS group, intermittent NPWT, continuous NPWT, and silver sulfadiazine were 107.43 ± 83.43, 178.07 ± 74.83, 146.10 ± 69.1, 126.03 ± 83.22, respectively(p = 0.457); on day 21 in NS group, intermittent NPWT, continuous NPWT, and silver sulfadiazine were 13.16 ± 16.86, 59.49 ± 20.72, 54.79 ± 46.59, 48.95 ± 39.84, respectively(p=0.169). There were no significant differences in each treatment group bacterial colonization(p>0.05). There were no significant correlation between bacterial colonization and remaining burn surface area (p>0.05).

Conclusion

While morphologically, the wound in NPWT treatment groups appeared better in granulation and crust formation, the remaining wound surface area and the number of bacterial colonization were not significantly difference compared to standard therapy (silver sulfadiazine and NS gauze). There were no significant correlation between the amount of bacterial colonization and remaining wound surface area on every treatment group.

•

Sepsis is one of cause burn injury mortality.

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NPWT is promising burn injury treatment.

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There was no significant difference of wound healing in various treatments.

The prognostic value of N-terminal pro-brain natriuretic peptide (NT-proBNP) in major burn patients with sepsis

The aim is to examine the prognostic value of N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with major burns and sepsis. We collected the data of major burn patients who were admitted to our department. We compared the age, sex, burn area, burn depth, length of hospitalization, and mortality rate between the sepsis group and non-sepsis group and compared NT-proBNP, procalcitonin (PCT), platelet count, Sequential Organ Failure Assessment (SOFA) score, and quick SOFA (qSOFA) score between the survivors and nonsurvivors in the sepsis group. Receiver operating characteristic (ROC) curves were used in sepsis patients to evaluate the prognostic value of NT-proBNP, PCT, SOFA score, qSOFA score, et al.. Kaplan-Meier survival curves were used to compare the 90-day survival curves of patients. Logistic regression analysis was used to analyse the risk factors that affect the prognosis of sepsis patients. There were 90 major burn patients with sepsis and 114 major burn patients without sepsis. The mortality rate for the major burn sepsis group was significantly higher than that for the non-sepsis group. The NT-proBNP level in sepsis patients in the nonsurvivor group was 2900 pg/mL, which was significantly higher than that in patients in the survivor group. Survival analysis showed that the mean survival time for the NT-proBNP >2000 pg/mL group was 15.08 days. Multivariate regression analysis indicated that NT-proBNP was an independent risk factor for mortality in burn patients with sepsis. NT-proBNP can be used as a prognostic marker in patients with major burns and sepsis.

Türkiye Güneydoğu Anadolu bölgesinde pediatrik yanık vakalarının analizi:10 yıllık retrospektif çalışma

Background: Burns continue to be a serious global public health problem all over the world, especially in developing countries. Materials and Methods: The age, gender, cause of injury, and total body surface area (TBSA) of the burn, complications, and mortality rate of 1,038 patients who were hospitalized in our burn center between January 1, 2010, and January 1, 2020, were analyzed. Results: The burned surface area was greater in boys than in girls. The mean burned body surface area for all patients was 9.2 ± 6.35, and the mortality rate was 1.45%. Hot liquids, such as tea, hot milk, hot water, and oily food, were the causes of burns in 84.7% of the patients. Hot objects, hot melted nylon, hot tandoor and embers, and hot asphalt accounted for 7.7% of the burns. Moreover, flame burns, electrical burns and frostbite, and other burn causes accounted for 5.6%, 1.2 %, and 0.8% of burn injuries, respectively. Conclusions: In our region, pediatric burns occurred mostly in boys under the age of three and in children whose parents had low educational levels living in rural areas. We believe that the burn prevention program should be adjusted according to these results.

Comparative Transcriptome Analysis of Superficial and Deep Partial-Thickness Burn Wounds in Yorkshire vs Red Duroc Pigs

Hypertrophic scars are a common negative outcome of deep partial-thickness burn wounds resulting in increased dermal thickness, wound area contracture, and inflammation of the affected area. The red Duroc and Yorkshire porcine breeds are common large animal models for studying dermal wounds due to their structural similarities to human skin; however, the porcine transcriptomic profiles of dermal burn wounds and healing process are not well known. In response, a longitudinal transcriptomic comparative study was conducted comparing red Duroc and Yorkshire superficial and DPT burn wounds to their respective control uninjured tissue. Using next-generation RNA-sequencing, total RNAs were isolated from burn wound tissue harvested at 0, 3, 7, 15, 30, and 60 days post-burn and mRNA-seq and gene expression read counts were generated. Significant differentially expressed genes relative to uninjured tissue were defined and active biological processes were determined using gene set enrichment analyses. Additionally, collagen deposition, α-SMA protein concentration, epidermal and dermal thickness measurements, and wound area changes in response to burn injury were characterized. Overall, the red Duroc pigs, in response to both burn wound types, elicited a more robust and prolonged inflammatory immune response, fibroblast migration and proliferation as well as heightened levels of extracellular matrix modulation relative to respective burn types in the Yorkshire pigs. Collectively, the red Duroc deep partial-thickness burn wounds produce a greater degree of hypertrohic scar like response compared to Yorkshire DPT burn wounds. These findings will facilitate future porcine burn studies down-selecting treatment targets and determining effects of novel therapeutic strategies.

Inhibition of Bruton's Tyrosine Kinase Protects Against Burn Sepsis-Induced Intestinal Injury

This study aimed to investigate the role and molecular mechanisms of Bruton's tyrosine kinase (BTK), a member of the Tec family in burn sepsis-induced intestinal injury. Eighty C57BL/6 mice were randomly divided into four groups: the sham group, the burn group, the burn + sepsis group, and the burn + sepsis + LFM-A13 (a selective BTK inhibitor) group. The dynamic expression profiles of BTK and p-BTK in the intestine were measured by Western blot analysis. Intestinal histopathological changes and cellular apoptosis were determined. Inflammatory cytokines in serum and intestinal tissue were examined through enzyme-linked immunosorbent assay. Myeloperoxidase (MPO) activity was determined via a colorimetric assay. Intestinal p-BTK expression in the burn+sepsis group was significantly increased compared with that in the sham and burn groups. In the burn + sepsis group, the p-BTK expression level increased over time, peaked at 12, and then decreased at 24 h. LFM-A13 administration significantly inhibited p-BTK expression in the intestine. In contrast to the sham and burn groups, the burn + sepsis group exhibited obvious histopathological changes, which gradually aggravated over time. LFM-A13 also reduced the histopathological changes and cellular apoptosis in intestinal tissues, inhibited the inflammatory cytokines IL-4, IL-6, and TNF-α in serum and intestinal tissues, and significantly inhibited the increase in intestinal MPO activity induced by burn sepsis. BTK activation is one important aspect of the signaling event that may mediate the release of the anti-inflammatory cytokine IL-4 and the pro-inflammatory cytokines IL-6 and TNF-α; oxidative stress; and intestinal cell apoptosis. Thus, it contributes to burn sepsis-induced intestinal injury.

Specific patterns of vital sign fluctuations predict infection and enable sepsis diagnosis in pediatric burn patients

Early recognition of the clinical signs of bloodstream infection in pediatric burn patients is key to improving survival rates in the burn unit. The objective of this study was to propose a simple scoring criteria that used readily available temperature, heart rate (HR) and mean arterial pressure (MAP) data to accurately predict bloodstream infection in pediatric burn patients. A retrospective chart review included 100 patients admitted to the pediatric burn unit for >20% total body surface area (TBSA) burn injuries. Each patient had multiple blood culture tests, and each test was treated as a separate and independent “infection event” for analysis. The time at each blood culture draw was time 0 for that event, and temperature, HR and MAP data was collected for 24 hours after the blood culture was drawn. “Infection events” included in this study had at least six complete sets of temperature, HR and MAP data entries. Median temperature, HR and MAP, as well as mean fever spikes, HR spikes and MAP dips, were compared between infection group (positive blood cultures) and control group (negative blood cultures). These vital sign fluctuations were evaluated individually and as a combination of all three as timely predictors of bloodstream infection. In addition, we tested the prediction of Gram-negative bacteria versus Gram-positive or fungi present in blood cultures. Patients in the infection group had significantly higher median temperatures (p<0.001), mean fever spikes (p<0.001) and mean HR spikes (p<0.001), compared to the control group. Using the combination scoring criteria to predict bloodstream infection, the strongest predictive values in the 24-hour timeframe had high sensitivity (93%) and specificity (81%). The predictive test metric based on vital sign spikes predicted Gram-negative bacteria, but with limited sensitivity (57%) and specificity (44%). A simple scoring criteria using a combination of fever spikes, HR spikes and MAP dips predicted bloodstream infection in pediatric burn patients, and can be feasibly implemented in routine clinical care. There is also potential to use the predictive metric to detect a few select organisms based on vital signs, however further work is necessary to enhance accuracy to levels that would allow consideration for clinical use.

Optimizing large-scale autologous human keratinocyte sheets for major burns-Toward an animal-free production and a more accessible clinical application

Background and Aims

Autologous keratinocyte sheets constitute an important component of the burn wound treatment toolbox available to a surgeon and can be considered a life‐saving procedure for patients with severe burns over 50% of their total body surface area. Large‐scale keratinocyte sheet cultivation still fundamentally relies on the use of animal components such as inactivated murine 3T3 fibroblasts as feeders, animal‐derived enzymes such as trypsin, as well as media components such as fetal bovine serum (FBS). This study was therefore aimed to optimize autologous keratinocyte sheets by comparing various alternatives to critical components in their production.

Methods

Human skin samples were retrieved from remnant operative tissues. Cell isolation efficiency and viability were investigated by comparing the efficacy of porcine‐derived trypsin and animal‐free enzymes (Accutase and TrypLESelect). The subsequent expansion of the cells and the keratinocyte sheet formation was analyzed, comparing various cell culture substrates (inactivated murine 3T3 fibroblasts, inactivated human fibroblasts, Collagen I or plain tissue culture plastic), as well as media containing serum or chemically defined animal‐free media.

Results

The cell isolation step showed clear cell yield advantages when using porcine‐derived trypsin, compared to animal‐free alternatives. The keratinocyte sheets produced using animal‐free serum were similar to those produced using 3T3 feeder layer and FBS‐containing medium, particularly in mechanical integrity as all grafts were liftable. In addition, sheets grown on collagen in an animal‐free medium showed indications of advantages in homogeneity, speed, reduced variability, and differentiation status compared to the other growth conditions investigated. Most importantly, the procedure was compatible with the up‐scaling requirements of major burn wound treatments.

Conclusion

This study demonstrated that animal‐free components could be used successfully to reduce the risk profile of large‐scale autologous keratinocyte sheet production, and thereby increase clinical accessibility.

A Prospective Observational Study Comparing Clinical Sepsis Criteria to Protein Biomarkers Reveals a Role for Vascular Dysfunction in Burn Sepsis

OBJECTIVES

To compare the diagnostic value of clinical sepsis criteria to novel protein biomarkers in the burn patient.

DESIGN

Prospective observational study.

SETTING

American Burn Association verified Burn Center ICU.

PATIENTS

Burn patients (n = 24) and healthy volunteers (n = 10).

INTERVENTIONS

Enrolled burn patients (n = 24) were stratified based on whether or not they met a clinical definition of sepsis. Four separate clinical criteria for sepsis were analyzed for their diagnostic sensitivity and specificity, which were compared to a panel of protein biomarkers. The most significant protein biomarkers were further analyzed via the area under the receiver operating characteristic curves (AUROCs).

MEASUREMENTS AND MAIN RESULTS

Of the clinical criteria, SEPSIS-2 criteria led to the highest AUROC (0.781; p < 0.001), followed by the quick Sequential Organ Failure Assessment score (AUROC = 0.670; p = 0.022). Multiplexing revealed a number of inflammatory proteins (complement C5) and matrix metalloproteinases (MMP1, MMP7) that were significantly elevated in septic samples compared with both healthy controls and nonseptic burn samples. Furthermore, three proteins associated with endothelial dysfunction and glycocalyx shedding revealed diagnostic potential. Specifically, syndecan-1, p-selectin, and galectin-1 were all significantly elevated in sepsis, and all resulted in an AUROC greater than 0.7; analyzing the sum of these three markers led to an AUROC of 0.808.

CONCLUSIONS

These data reveal several potential biomarkers that may help with sepsis diagnosis in the burn patient. Furthermore, the role of endotheliopathy as a mechanistic etiology for sepsis after burns warrants further investigation.

Immature granulocyte percentage for prediction of sepsis in severe burn patients: a machine leaning-based approach

BACKGROUND

Of the existing sepsis markers, immature granulocytes (IG) most frequently reflect the presence of an infection. The importance of IG as an early predictor of sepsis and bacteremia is evaluated differently for each study. This study aimed to evaluate the effectiveness of the Sysmex XN series' IG% as an independent prognostic indicator of sepsis using machine learning.

METHODS

A total of 2465 IG% results from 117 severe burn patients in the intensive care unit of one institution were retrospectively analyzed. We evaluated the IG% for sepsis using the receiver operating characteristic, logistic regression, and partial dependence plot analyses. Clinical characteristics and other laboratory markers associated with sepsis, including WBC, procalcitonin, and C-reactive protein, were compared with the IG% values.

RESULTS

Twenty-six of the 117 patients were diagnosed with sepsis. The median IG% value was 2.6% (95% CI: 1.4-3.1). The area under the receiver operating characteristic curve was 0.77 (95% CI: 0.78-0.84) and the optimal cut-off value was 3%, with a sensitivity of 76.9% and specificity of 68.1%. The partial dependence plot of IG% on predicting sepsis showed that an IG% < 4% had low predictability, but increased thereafter. The interaction plot of IG% and C-reactive protein showed an increase in sepsis probability at an IG% of 6% and C-reactive protein of 160 mg/L.

CONCLUSIONS

IG% is moderately useful for predicting sepsis. However, since it can be determined from routine laboratory test results and requires no additional intervention or cost, it could be particularly useful as an auxiliary marker.

Efficacy of two-stage Meek micrografting in patients with severe burns

BACKGROUND

Burns are common injuries associated with high disability and mortality. In recent years, Meek micrografting technique has been gradually applied for the wound treatment of severe burns. However, the efficacy of two-stage Meek micrografting in patients with severe burns keeps unclear.

METHODS

The data of eligible patients with severe burns who were admitted to Southwest Hospital of the Third Military Medical University from January 2013 to December 2019 were retrospectively analysed. The patients were divided into two groups according to the Meek micrografting method: one-stage skin grafting (group A) and two-stage skin grafting (group B). The baseline data, survival rate of skin graft, length of hospital stay, treatment costs, laboratory data and cumulative survival were statistically analysed.

RESULTS

127 patients (91 in group A and 36 in group B) were included in the study. There were no significant difference in the baseline data, the length of hospital stay and treatment costs between the two groups. The survival rate of skin graft was higher in group B. Total protein and albumin level, platelet count in group B were superior to those in group A, while there were no difference in other laboratory data (prealbumin, serum creatinine, urea nitrogen, cystatin C, blood cultures, wound exudate cultures) and cumulative survival between the two groups.

CONCLUSION

Our results demonstrated that staged Meek micrografting could improve the survival rate of skin graft, by reducing the risks of hypoproteinaemia, hypoalbuminemia and low platelet counts after adequate resuscitation.

On the Nonspecific Resistance in Burn Injury: Pathophysiological Aspects (Review)

An analysis of nonspecific resistance in burn patients is conducted. The role of subpopulations of neutrophils and monocytes/ macrophages in severe burn injury is discussed. The significance of blood cells for the burn-induced immune dysfunction, susceptibility to sepsis and multiple organ failure is underscored. The involvement of secondary complications in the development of morbidity and mortality in patients with burn injury is shown. New approaches to identifying individuals with a risk of adverse outcome are considered.

Bacteriological profile, antibiotic susceptibility and factors associated with neonatal Septicaemia at Kilembe mines hospital, Kasese District Western Uganda

Introduction

Neonatal septicaemia is one of the most common leading causes of neonatal morbidity and mortality in developing countries. It is estimated to affect more than 30 million people worldwide annually, potentially leading to 6 million deaths.

Objective(s)

To determine the prevalence, bacteriological profile, antibiotic susceptibility and factors associated with neonatal septicaemia among neonates suspected to sepsis at Kilembe mines hospital.

Methods

We conducted a descriptive cross-sectional study, where purposive sampling technique was used and blood was drawn from 122 neonates suspected to sepsis attending Kilembe Mines Hospital during the period (July to November 2020). Specimens were inoculated in Brain heart infusion broth, transported to Fortportal Regional Referral Hospital, plated daily up to 7 days on blood, chocolate, MacConkey agar and incubated in aerobic and 5% carbondioxide. Pure colonies were identified by Gram stain, biochemical tests and antibiotic sensitivities obtained by Kirby Bauer disc diffusion method. Associations were tested using Chi square with Fisher’s exact or Yates correction tests where necessary and statistical significance was set at P < 0.05. Stata (version 14) used for statistical analysis.

Results

Blood cultures were positive in 59.0% cases with 55.5% male and 44.4% female. EOS was present in 56.9% and LOS 43.1% of the cases. Gram negative (56.9%) organisms were most implicated with neonatal septicaemia than Gram positives ones (43.1%). Gram positive organisms exhibited better susceptibility to amikacin, linezolid and vancomycin but more resistant to ampicillin and gentamicin. Of the aminoglycosides, amikacin exhibited a verge over netilmicin and gentamicin against Gram negative isolates. Risk factors of neonatal septicaemia were mother’s age of ≥25 years, employed mothers, tertiary-level of education, SVD, ANC attendance of ≥4 times, UTI during pregnancy, PROMS, foul Smelling liquor, urban residence, neonatal birth weight of ≥2500 g, Apgar score 1st and 5th min ≥6 and resuscitation.

Conclusion

Multi-drug resistant organisms were isolated. Therefore caution is required in selection of antibiotic therapy and avoid empirical treatment.

Dexmedetomidine protects against burn-induced intestinal barrier injury via the MLCK/p-MLC signalling pathway

BACKGROUND

Evidence suggests that sedative dexmedetomidine can prevent intestinal dysfunction. However, the specific mechanisms of its protective effects against burn-induced intestinal barrier injury remain unclear. We aimed to explore the possible positive effects of dexmedetomidine on burn-induced intestinal barrier injury and the effects the myosin light chain kinase (MLCK)/phosphorylated myosin light chain (p-MLC) signalling pathway in an experimental model of burn injury.

METHODS

In this study, the plasma concentration of fluorescein isothiocyanate-labelled dextran (FITC-dextran) was measured. Histological changes were evaluated using haematoxylin and eosin (HE) staining. Tight junction proteins were evaluated by western blot and immunofluorescence analyses to assess the structural integrity of intestinal tight junctions. The level of inflammation was detected by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The results shows that the increase in intestinal permeability caused by burn injury is accompanied by histological damage to the intestine, decreases in the expression of the tight junction proteins Zonula Occludens-1 (ZO-1) and Occludin, increases in inflammatory cytokine levels and elevation of both MLCK protein expression and MLC phosphorylation. After dexmedetomidine treatment, the burn-induced changes were ameliorated.

CONCLUSIONS

In conclusion, dexmedetomidine exerted an anti-inflammatory effect and protected tight junction complexes against burn‑induced intestinal barrier damage by inhibiting the MLCK/p-MLC signalling pathways.

CNS-Spleen Axis - a Close Interplay in Mediating Inflammatory Responses in Burn Patients and a Key to Novel Burn Therapeutics

Severe burn-induced inflammation and subsequent hypermetabolic response can lead to profound infection and sepsis, resulting in multiple organ failure and high mortality risk in patients. This represents an extremely challenging issue for clinicians as sepsis is the leading cause of mortality in burn patients. Since hyperinflammation and immune dysfunction are a result of an immune imbalance, restoring these conditions seem to have promising benefits for burn patients. A key network that modulates the immune balance is the central nervous system (CNS)-spleen axis, which coordinates multiple signaling pathways, including sympathetic and parasympathetic pathways. Modulating inflammation is a key strategy that researchers use to understand neuroimmunomodulation in other hyperinflammatory disease models and modulating the CNS-spleen axis has led to improved clinical outcomes in patients. As the immune balance is paramount for recovery in burn-induced sepsis and patients with hyperinflammatory conditions, it appears that severe burn injuries substantially alter this CNS-spleen axis. Therefore, it is essential to address and discuss the potential therapeutic techniques that target the CNS-spleen axis that aim to restore homeostasis in burn patients. To understand this in detail, we have conducted a systematic review to explore the role of the CNS-spleen axis and its impact on immunomodulation concerning the burn-induced hypermetabolic response and associated sepsis complications. Furthermore, this thorough review explores the role of the spleen, CNS-spleen axis in the ebb and flow phases following a severe burn, how this axis induces metabolic factors and immune dysfunction, and therapeutic techniques and chemical interventions that restore the immune balance via neuroimmunomodulation.

A Nonlethal Murine Flame Burn Model Leads to a Transient Reduction in Host Defenses and Enhanced Susceptibility to Lethal Pseudomonas aeruginosa Infection

Of the 486,000 burn injuries that required medical treatment in the United States in 2016, 40,000 people were hospitalized, with >3,000 fatalities. After burn injury, humans are at increased risk of sepsis and mortality from infections caused by Pseudomonas aeruginosa, an opportunistic pathogen. We hypothesize that systemic events were initiated from the burn that increased the host's susceptibility to P. aeruginosa. A nonlethal 10% total body surface area (TBSA), full-thickness flame burn was performed in CD-1 mice without and with subsequent P. aeruginosa (strain M2) infection. The 50% lethal dose for subcutaneous infection with P. aeruginosa M2 at the burn site immediately after the burn decreased by 6 log, with mortality occurring between 18 and 26 h, compared with P. aeruginosa-infected mice without burn injury. Bacteria in distal organs were detected by 18 h, concurrent with the onset of clinical symptoms. Serum proinflammatory cytokines (interleukin-6 [IL-6], IL-1β, gamma interferon, and tumor necrosis factor alpha) and the anti-inflammatory cytokine IL-10 were first detected at 12 h postburn with infection and continued to increase until death. Directly after burn alone, serum levels of HMGB1, a danger-associated molecular pattern and TLR4 agonist, transiently increased to 50 ng/ml before returning to 20 ng/ml. Burn with P. aeruginosa infection increased serum HMGB1 concentrations >10-fold (250 ng/ml) at the time of death. This HMGB1-rich serum stimulated TLR4-mediated NF-κB activation in a TLR4 reporter cell line. Treatment of infected burned mice with P5779, a peptide inhibitor of HMGB1, increased the mean survival from 23 to 42 h (P < 0.0001). We conclude that the high level of serum HMGB1, which preceded the increase in proinflammatory cytokines, is associated with postburn mortality.

Metal chelation attenuates oxidative stress, inflammation, and vertical burn progression in a porcine brass comb burn model

Oxidative stress and inflammation may mediate cellular damage and tissue destruction as the burn wound continues to progress after the abatement of the initial insult. Since iron and calcium ions play key roles in oxidative stress, this study tested whether topical application of a metal chelator proprietary lotion (Livionex Formulation (LF) lotion), that contains disodium EDTA as a metal chelator and methyl sulfonyl methane (MSM) as a permeability enhancer, would prevent progression or reduce burn wound severity in a porcine model. We have reported earlier that in a rat burn model, LF lotion reduces thermal injury progression. Here, we used the porcine brass comb burn model that closely mimics the human condition for contact burns and applied LF lotion every 8 h starting 15 min after the injury. We found that LF lotion reduces the depth of cell death as assessed by TUNEL staining and blood vessel blockage in the treated burn sites and interspaces. The protein expression of pro-inflammatory markers IL-6, TNF-a, and TNFα Converting Enzyme (TACE), and lipid aldehyde production (protein-HNE) was reduced with LF treatment. LF lotion reversed the burn-induced decrease in the aldehyde dehydrogenase (ALDH-1) expression in the burn sites and interspaces. These data show that a topically applied EDTA-containing lotion protects both vertical and horizontal burn progression when applied after thermal injury. Curbing burn wound conversion and halting the progression of second partial burn to third-degree full-thickness burn remains challenging when it comes to burn treatment strategies during the acute phase. Burn wound conversion can be reduced with targeted treatments to attenuate the oxidative and inflammatory response in the immediate aftermath of the injury. Our studies suggest that LF lotion could be such a targeted treatment.

The Role of DAMPS in Burns and Hemorrhagic Shock Immune Response: Pathophysiology and Clinical Issues. Review

Severe or major burns induce a pathophysiological, immune, and inflammatory response that can persist for a long time and affect morbidity and mortality. Severe burns are followed by a "hypermetabolic response", an inflammatory process that can be extensive and become uncontrolled, leading to a generalized catabolic state and delayed healing. Catabolism causes the upregulation of inflammatory cells and innate immune markers in various organs, which may lead to multiorgan failure and death. Burns activate immune cells and cytokine production regulated by damage-associated molecular patterns (DAMPs). Trauma has similar injury-related immune responses, whereby DAMPs are massively released in musculoskeletal injuries and elicit widespread systemic inflammation. Hemorrhagic shock is the main cause of death in trauma. It is hypovolemic, and the consequence of volume loss and the speed of blood loss manifest immediately after injury. In burns, the shock becomes evident within the first 24 h and is hypovolemic-distributive due to the severely compromised regulation of tissue perfusion and oxygen delivery caused by capillary leakage, whereby fluids shift from the intravascular to the interstitial space. In this review, we compare the pathophysiological responses to burns and trauma including their associated clinical patterns.

Role of Procalcitonin and C-reactive Protein as Marker of Sepsis in Major Burn Patients: A Systematic Review and Meta-analysis

AIM: Although absolute values for C-reactive protein (CRP) and procalcitonin (PCT) are well known to predict sepsis, it remains unclear how their diagnostic value in major burn patients as metabolic changes in burn patient mimic signs and symptoms for sepsis. This paper attempts to clarify these points for both of the markers. METHODS: A comprehensive literature search of PubMed, Scopus, DOAJ, Web of Science, and the Cochrane Library databases for studies published up to June 1, 2020, that evaluated PCT and/or CRP as a marker for diagnosing sepsis in burn patients was conducted. Review Manager 5.3 was used to analyze the data. RESULTS: A total of 11 literatures were obtained. The combined sensitivity and specificity for PCT as assessed by meta-analysis were 88% and 89%, respectively. The combined sensitivity and specificity of CRP were described as 85.5% and 57.5%, respectively. Meta-analysis cannot be performed for CRP parameters because there are only two literatures that include CRP diagnostic test values. DISCUSSION: PCT and CRP have additional diagnostic value for sepsis in patients with major burns. The pooled sensitivity and specificity of PCT are excellent. Although the difference in sensitivity between PCT and CRP is not very large, there are distinct differences in specificity. A low CRP specificity value will show many “false positives” when CRP is used as a biomarker. CONCLUSION: PCT provides a better diagnostic value than CRP in cases of sepsis in major burn patients. More study on combination of biomarker, clinical presentation, and microbial culture for diagnosing sepsis are needed. Further large-scale research with cohort or case control design should be done.

Impact of COVID-19 on Patient Trends and Outcome: Results from a Tertiary Care Burn and Plastic Unit in Northern India

Background  Burn and trauma injuries need emergency care and resuscitation, which required uninterrupted delivery of inpatient care services during the coronavirus disease 2019 (COVID-19) pandemic. Burn patients are physiologically immunocompromised, increasing the risk of COVID-19 infection in them. This study analyzes the impact of COVID-19 pandemic on patient trends in a burn and plastic unit and assesses the effect of COVID-19 infection in burns.

Methods  This single-center, retrospective observational case–control study was conducted in the Department of Burns, Plastic and Maxillofacial Surgery of a tertiary care hospital in New Delhi, India. Patient data was collected from April 1, 2019 to August 10, 2019 and from April 1, 2020 to August 10, 2020. All data of burns and trauma patients collected was analyzed and compared.

Results  There were total 350 admissions during COVID time period and 562 admissions during non-COVID time period. The admission rate, type of burn injury, and death rate did not vary significantly during the two time periods. Thermal burn was the most common type of burn injury. There were total 18 cases diagnosed to be COVID-19 positive during the pandemic. There were two deaths among COVID-19 positive burn cases.

Conclusion  This study finds no difference in patient patterns during COVID and non-COVID time period. Amongst burn patients, no increased risk of COVID-19 infection is seen with larger body surface area of burns. No increase in mortality is seen in burn patients infected with COVID-19.

Predictive Value of the Prognostic Nutrition Index for the Prognosis of Patients With Severe Burns Treated With the Meek Graft

The Meek technique is currently a key method for treating wounds in severely burned patients. The survival rate of skin grafts is an important factor affecting the success rate of treatment. The purpose of this study was to investigate the effect of the preoperative prognostic nutritional index (PNI) on the survival rate of skin grafts in patients treated with the Meek technique in the early stage of severe burns. We retrospectively analyzed the data of severely burned patients who were treated at the burn center between January 2013 and December 2019 and met the inclusion criteria. The albumin (ALB) level and lymphocyte count obtained 1 day before the operation was used to calculate the preoperative PNI (PNI = serum ALB level [g/L] + 5 × total number of peripheral blood lymphocytes [×109/L]). According to the survival rates of skin grafts 14 days after the operation, patients with severe burns were divided into a group with good skin graft survival (survival rate ≥75%, abbreviated as group G) and a group with poor skin graft survival (survival rate <75%, abbreviated as group P). Receiver-operating characteristic (ROC) curves and univariate and multivariate analyses were used to evaluate the predictive value of the preoperative PNI for the prognosis of patients treated with the Meek technique. One hundred and twenty-one patients were enrolled in this study. Groups G (n = 66 cases) and P (n = 55 cases) did not have significant differences in age, sex, and body mass index (P > .05). The total burned surface area, burn index, platelet-to-lymphocyte ratio, preoperative platelet count, operative time, total protein, albumin level, globulin level, and PNI were the risk factors affecting the survival of Meek grafts. The burn index was an independent risk factor for poor skin graft survival (odds ratio [OR]: 1.049, 95% confidence interval [CI]: 1.020-1.079; P < .05). The preoperative PNI was a protective factor against poor skin graft survival (OR: 0.646, 95% CI: 0.547-0.761; P < .05). The ROC curve determined that the optimal cut-off value for the preoperative PNI was 34.98. There were 59 cases with PNI > 34.98 (the high PNI group) and 62 cases with PNI < 34.98 (the low PNI group). The survival rate of skin grafts in patients with a high PNI was generally significantly higher than that of patients with a low preoperative PNI (P < .05). Five (8.47%) patients in the high PNI group died, compared with 16 (25.8%) patients in the low PNI group. The difference in the mortality rate between the two groups was significant (P < .05). Preoperative PNI can be used as a predictor of the survival rate of skin grafts in patients treated with the Meek technique in the early stage of severe burns.

Contemporary Aspects of Burn Care

The past one hundred years have seen tremendous improvements in burn care, allowing for decreased morbidity and mortality of this pathology. The more prominent advancements occurred in the period spanning 1930-1980; notably burn resuscitation, early tangential excision, and use of topical antibiotic dressings; and are well documented in burn literature. This article explores the advancements of the past 40 years and the areas of burn management that are presently topics of active discussion and research.

Skin and sepsis: contribution of dermatology to a rapid diagnosis

In patients who develop sepsis, whether due to primary, secondary or metastatic lesions, the skin is frequently affected. However, there are unresolved aspects regarding the general clinical manifestations in the skin or the prognosis and/or therapeutic implications. The main challenge in the approach to sepsis is its early diagnosis and management. In this review, we address the sepsis-skin relationship and the potential impact of early dermatological intervention on the septic patient through ten basic questions. We found little evidence of the participation of the dermatologist in sepsis alert programs. There are early skin changes that may alert clinicians on a possible sepsis, such as skin mottling or variations in acral skin temperature. In addition, the skin is an accessible and highly cost-effective tissue for etiological studies of some forms of sepsis (e.g., meningococcal purpura) and its involvement defines the prognosis of certain patients (e.g., infective endocarditis).

A Retrospective Study of Factors Influencing the Survival of Modified Meek Micrografting in Severe Burn Patients

Modified Meek micrografting is a common method for treating severe burn patients. This study was to analyze the factors affecting the survival of modified Meek micrografting, thereby improving the survival rate of skin grafts. Eighty-three patients who underwent modified Meek micrografting were analyzed. According to the survival rate of skin graft after operation, the patients were divided into good skin survival group (GSSG, survival rate ≥ 70%, 47 cases) and poor skin survival group (PSSG, survival rate < 70%, 36 cases). The baseline data, surgical information, perioperative laboratory indicators, and prognosis of the patients were statistically analyzed. The univariate analysis and repeated measurement showed the burn severity, Meek skin graft area, duration of anesthesia, the postoperative sepsis shock, the mortality, the neutrophils percentage on the third day after surgery (NEU3), and the growth rate of neutrophils percentage from the first to third day after surgery (NEU3-1%) in the GSSG were significantly lower than those in the PSSG, whereas the perioperative average albumin levels and the perioperative average pre-albumin levels were higher. Receiver operating characteristic curve showed that the NEU3 had a good predictive value for the survival of skin slices. Maintaining perioperative albumin levels at a high level, controlling perioperative infection, and shortening the operation time as much as possible may improve the survival rate of modified Meek micrografting.

The pathogenesis and diagnosis of sepsis post burn injury

Burn is an under-appreciated trauma that is associated with unacceptably high morbidity and mortality. Although the survival rate after devastating burn injuries has continued to increase in previous decades due to medical advances in burn wound care, nutritional and fluid resuscitation and improved infection control practices, there are still large numbers of patients at a high risk of death. One of the most common complications of burn is sepsis, which is defined as “severe organ dysfunction attributed to host's disordered response to infection” and is the primary cause of death in burn patients. Indeed, burn injuries are accompanied by a series of events that lead to sepsis and multiple organ dysfunction syndrome, such as a hypovolaemic state, immune and inflammatory responses and metabolic changes. Therefore, clear diagnostic criteria and predictive biomarkers are especially important in the prevention and treatment of sepsis and septic shock. In this review, we focus on the pathogenesis of burn wound infection and the post-burn events leading to sepsis. Moreover, the clinical and promising biomarkers of burn sepsis will also be summarized.

Application of critical care scores in severely burned patients

Early detection of sepsis is of crucial importance in patients with severe burn injuries. However, according to the S1-guideline , based on SIRS criteria, the early diagnosis of sepsis in severely burned patients is difficult. The value of the new definition of sepsis based on sequential organ failure assessment (SOFA) according to S3-guidelines for patients with severe burn injuries is not described in detail in literature.We analyzed retrospectively all data during the period 2014-2018 from the electronic patient information system. Using Receiver operating characteristic (ROC) curve the area under the curve (AUC) was calculated for diagnostic value of procalcitonin (PCT), SIRS and SOFA score according to the burned total body surface area (TBSA). 651 patients with burn injuries were admitted to our burn unit, 315 of them had burn injuries affecting more than 10% body surface area with partial to full thickness burn (grade 2-4) . In this group, 59 patients showed one or more septic events in the course of the intensive care treatment, defined by positive blood stream infection. Both S1- and S3- guidelines were inappropriate to diagnose sepsis in patients with severe burn injuries. Due to pathophysiological changes of the body function in severely burned patients, that show features of both SIRS and pathological SOFA scores (> 2 points) at the outset of burn injury, the diagnosis of sepsis associated with burns is intricate in this patient group. Assessing data for potential hallmarks of sepsis in burn patients we found PCT to show significant correlation with sepsis.

Mortality incidence among critically ill burn patients infected with multidrug-resistant organisms: A retrospective cohort study

INTRODUCTION

Many risk factors have been reported to increase mortality among burn patients. Previously, a higher mortality incidence was reported in acute burn patients infected with multidrug-resistant organisms (MDROs) when compared to patients infected with non-MDROs. However, considering this as an independent risk factor for mortality in acute burn patients is not yet confirmed.

METHODS

We conducted an observational retrospective study in Qatar. We included adult patients admitted to the surgical intensive care unit (ICU) between January 2015 and December 2017 with burn injuries involving either at least 15% of the total body surface area (TBSA) or less than 15% with facial involvement. All patients developed infection with a positive culture of either MDRO or non-MDRO. The primary outcome was in-hospital mortality. Other outcomes included days of mechanical ventilation, ICU, length of stay in hospital, and requirement of vasoactive agents.

RESULTS

Fifty-eight patients were included in the final analysis: 33 patients in the MDRO group and 25 patients in the non-MDRO group. Six patients (18.2%) died in the MDRO group versus four patients (16%) in the non-MDRO group (P = 1). No significant difference was observed between the two groups with regard to the ICU length of stay. However, there was a trend towards increased median length of stay in hospital in the MDRO group: 62 days versus 45 days in the non-MDRO group (P = 0.057). No significant differences were observed in the other outcomes.

CONCLUSION

In severely burned patients, infection with MDRO was not associated with increased mortality. There was a trend towards increased hospitalisation in MDRO-infected patients. Further studies with a larger sample size are needed to confirm these results.

LAY SUMMARY

Many factors affect mortality in burn patients admitted to the intensive care unit, such as age, total body surface area involved in the injury, and others. In this retrospective study, we evaluated whether wound infection with a bacterial organism resistant to multiple classes of antibiotics (multidrug-resistant) is considered an independent risk factor for mortality in critically ill burn patients. We included 58 patients requiring intensive care admission with burn injuries involving 15% or more of the total body surface area or less than 15% but with facial involvement. A total of 33 patients were infected with multidrug-resistant organisms (MDROs) and 25 patients with non-MDROs. Six patients (18.2%) from the MDRO group died versus four (16%) in the non-MDRO group. The MDRO group required a longer stay in hospital and an average of one more day on a mechanical ventilator. We concluded that wound infection with MDROs might not increase mortality when compared to wound infection with non-MDROs, although other studies with a larger number of patients involved need to be conducted to validate these results.