Septic predictor index: A novel platform to identify thermally injured patients susceptible to sepsis

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.

Predicting sepsis using a combination of clinical information and molecular immune markers sampled in the ambulance

Sepsis is a time dependent condition. Screening tools based on clinical parameters have been shown to increase the identification of sepsis. The aim of current study was to evaluate the additional predictive value of immunological molecular markers to our previously developed prehospital screening tools. This is a prospective cohort study of 551 adult patients with suspected infection in the ambulance setting of Stockholm, Sweden between 2017 and 2018. Initially, 74 molecules and 15 genes related to inflammation were evaluated in a screening cohort of 46 patients with outcome sepsis and 50 patients with outcome infection no sepsis. Next, 12 selected molecules, as potentially synergistic predictors, were evaluated in combination with our previously developed screening tools based on clinical parameters in a prediction cohort (n = 455). Seven different algorithms with nested cross-validation were used in the machine learning of the prediction models. Model performances were compared using posterior distributions of average area under the receiver operating characteristic (ROC) curve (AUC) and difference in AUCs. Model variable importance was assessed by permutation of variable values, scoring loss of classification as metric and with model-specific weights when applicable. When comparing the screening tools with and without added molecular variables, and their interactions, the molecules per se did not increase the predictive values. Prediction models based on the molecular variables alone showed a performance in terms of AUCs between 0.65 and 0.70. Among the molecular variables, IL-1Ra, IL-17A, CCL19, CX3CL1 and TNF were significantly higher in septic patients compared to the infection non-sepsis group. Combing immunological molecular markers with clinical parameters did not increase the predictive values of the screening tools, most likely due to the high multicollinearity of temperature and some of the markers. A group of sepsis patients was consistently miss-classified in our prediction models, due to milder symptoms as well as lower expression levels of the investigated immune mediators. This indicates a need of stratifying septic patients with a priori knowledge of certain clinical and molecular parameters in order to improve prediction for early sepsis diagnosis.Trial registration: NCT03249597. Registered 15 August 2017.

EVALUATING SEPSIS CRITERIA IN DETECTING ALTERATIONS IN CLINICAL, METABOLIC, AND INFLAMMATORY PARAMETERS IN BURN PATIENTS

ABSTRACT

Sepsis has become the leading cause of death in burn patients. Furthermore, sepsis and septic complications result in significant morbidities and longer hospitalization, which has profound impacts on the healthcare system. Despite this, sepsis in burn patients is surprisingly poorly understood and characterized. This retrospective, single-institution cohort study aimed to increase our understanding of the septic response after burns. We hypothesized that different sepsis definitions will results in distinctive septic trajectories and biochemical patterns after injury. Sepsis was defined by our burn center-specific prospective definition, the American Burn Association criteria, Sepsis-3 criteria, and the Mann-Salinas criteria. Applying these definitions, we compared clinical, metabolic, and inflammatory markers in septic and nonseptic burn patients. We found that the Sepsis-3 criteria are the most reliable screening tool used before clinical diagnoses for detecting sepsis trajectories and biochemical patterns. Moreover, we characterized distinct temporal alterations in biomarkers during the pre- and post-septic periods in burn patients, which may be incorporated into future sepsis definitions to improve the accuracy of a sepsis diagnosis in burn patients.

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.

Potential Targets to Mitigate Trauma- or Sepsis-Induced Immune Suppression

In sepsis and trauma, pathogens and injured tissue provoke a systemic inflammatory reaction which can lead to overwhelming inflammation. Concurrent with the innate hyperinflammatory response is adaptive immune suppression that can become chronic. A current key issue today is that patients who undergo intensive medical care after sepsis or trauma have a high mortality rate after being discharged. This high mortality is thought to be associated with persistent immunosuppression. Knowledge about the pathophysiology leading to this state remains fragmented. Immunosuppressive cytokines play an essential role in mediating and upholding immunosuppression in these patients. Specifically, the cytokines Interleukin-10 (IL-10), Transforming Growth Factor-β (TGF-β) and Thymic stromal lymphopoietin (TSLP) are reported to have potent immunosuppressive capacities. Here, we review their ability to suppress inflammation, their dynamics in sepsis and trauma and what drives the pathologic release of these cytokines. They do exert paradoxical effects under certain conditions, which makes it necessary to evaluate their functions in the context of dynamic changes post-sepsis and trauma. Several drugs modulating their functions are currently in clinical trials in the treatment of other pathologies. We provide an overview of the current literature on the effects of IL-10, TGF-β and TSLP in sepsis and trauma and suggest therapeutic approaches for their modulation.

Review of Sepsis in Burn Patients in 2020

Background: Severe burn injury results in substantial damage to the skin, inhibiting its ability to perform as the primary barrier to infection. Additionally, severe burn injury can lead to critical illness and extensive time in the intensive care unit (ICU). These two factors work to increase the risk of sepsis in the burn patient compared with other hospitalized patients. The increased risk of sepsis is compounded by the difficulty of diagnosing sepsis in severely burned patients because the pathophysiology of large burns mimics sepsis, leading to possible delay in diagnosis and initiation of treatment. Methods: A literature review was performed to discuss and review the diagnostic difficulties and criteria used to identify patients with sepsis. Additionally, the most current management of sepsis was reviewed and described in caring for burn patients with sepsis. Results: The incidence of sepsis in patients with more than 20% total body surface area (TBSA) burns is between 3% and 30% and is the most common cause of death in the burn patient, with pneumonia being the most common etiology. Several different diagnostic criteria for diagnosing sepsis in burn patients exist, however, none of these criteria have proven to be superior to clinical diagnosis by an experienced burn surgeon. As with sepsis in other patient populations, prompt diagnosis, initiation of antibiotic agents, and source control remain the standard management of sepsis in the burn patient. Conclusions: Because of the loss of the primary infection barrier function of the skin after a substantial burn injury, this patient population is at increased risk for sepsis. Because of the pathophysiology of burn injuries, diagnosing sepsis in the burn population remains challenging. Understanding the most common etiologies of sepsis in burn patients may help with more expedient diagnosis and initiation of treatment.

Sepsis Definitions in Burns

Background: Sepsis is the leading cause of death in burns. Despite its importance, sepsis lacks a proper definition. An established definition will lead to early and accurate diagnosis, prompt treatment, and a reduced mortality rate. The aim of this work is to discuss current definitions and to look ahead at novel definitions with clinical implications. Method: A review of the current understanding of sepsis definitions in burns. Results: Adaptation of sepsis definitions in the general population and specific burn definitions have gotten better but still need improvements and, potentially, incorporation of molecular, laboratory, patient-specific, and clinical factors. This work includes the history, evolution, and predictive value of current definitions of sepsis in burns. A review of current and future markers of sepsis and potentially useful definitions are presented. Conclusions: Sepsis definitions have evolved over the last decades and will continue to do so. We believe the best definition in burn patients is the Sepsis-3 that was developed originally for critically ill patients. However, there are several studies investigating more specific definitions with better sensitivity and specificity.

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.

Status and Challenges of Predicting and Diagnosing Sepsis in Burn Patients

Burns are a common form of trauma that account for more than 300,000 deaths each year worldwide. Survival rates have improved over the past decades because of improvements in nutritional and fluid support, burn wound care, and infection control practices. Death, however, remains unacceptably high. The primary cause of death has changed over the last decades from anoxic causes to now predominantly infections and sepsis. Sepsis and septic complications are not only major contributors to poor outcomes, but they further result in longer hospital stay and higher healthcare costs. Despite the importance of infections and sepsis, the diagnosis and prediction remain a major challenge. To date, no clear diagnostic criteria or predictive formula exist that can predict reliably the occurrence of sepsis and infections. This review will highlight and discuss current definitions and criteria for diagnosis as well as predictive biomarkers of sepsis in patients with burns. It will also present the diagnostic tools employed, such as procalcitonin, C-reactive protein, and cytokines. We will discuss the benefits and shortcomings of different treatment modalities in the context of sepsis prevention. Last, we identify new therapeutic strategies for sepsis prediction and present future considerations to prevent sepsis in patients with burns. Minimizing and preventing septic complications through early detection would significantly benefit patients and necessitate continued research to unravel new biomarkers and mechanisms. Subsequent studies need to take a fresh perspective and consider the implementation of patient-centered therapeutic strategies.