A new marker of sepsis post burn injury?*

Early Autocalibrated Arterial Waveform Analysis for the Management of Burn Shock-A Cohort Study

Adequate fluid therapy is crucial for resuscitation after major burns. To adapt this to individual patient demands, standard is adjustment of volume to laboratory parameters and values of enhanced hemodynamic monitoring. To implement calibrated parameters, patients must have reached the intensive care unit (ICU). The aim of this study was, to evaluate the use of an auto-calibrated enhanced hemodynamic monitoring device to improve fluid management before admission to ICU. We used PulsioflexProAqt® (Getinge) during initial treatment and burn shock resuscitation. Analysis was performed regarding time of measurement, volume management, organ dysfunction, and mortality. We conducted a monocentre, prospective cohort study of 20 severely burned patients, >20% total body surface area (TBSA), receiving monitoring immediately after admission. We compared to 57 patients, matched in terms of TBSA, age, sex, and existence of inhalation injury out of a retrospective control group, who received standard care. Hemodynamic measurement with autocalibrated monitoring started significantly earlier: 3.75(2.67-6.0) hours (h) after trauma in the study group versus 13.6(8.1-17.5) h in the control group (P < .001). Study group received less fluid after 6 h: 1.7(1.2-2.2) versus 2.3(1.6-2.8) ml/TBSA%/kg, P = .043 and 12 h: 3.0(2.5-4.0) versus 4.2(3.1-5.0) ml/TBSA%/kg, P = .047. Dosage of norepinephrine was higher after 18 h in the study group: 0.20(0.12-0.3) versus 0.08(0.02-0.18) µg/kg/min, P = .014. The study group showed no adult respiratory distress syndrome versus 21% in the control group, P = .031. There was no difference in other organ failures, organ replacement therapy, and mortality. The use of auto-calibrated enhanced hemodynamic monitoring is a fast and feasible way to guide early fluid therapy after burn trauma. It reduces the time to reach information about patient's volume capacity. Management of fluid application changed to a more restrictive fluid use in the early period of burn shock and led to a reduction of pulmonary complications.

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.

Diagnosing sepsis in the ICU: Comparison of a gene expression signature to pre-existing biomarkers

PURPOSE

We aimed to identify a gene signature that discriminates between sepsis and aseptic inflammation in patients administered antibiotics in the intensive care unit and compare it to commonly utilised sepsis biomarkers.

METHODS

91 patients commenced on antibiotics were retrospectively diagnosed as having: (i) blood culture positive sepsis; (ii) blood culture negative sepsis; or (iii) aseptic inflammation. Bloods were collected after <24 h of antibiotic commencement for both gene expression sequencing analysis and measurement of previously identified biomarkers.

RESULTS

53 differentially expressed genes were identified that accurately discriminated between blood culture positive sepsis and aseptic inflammation in a cohort of patients given antibiotics [aROC 0.97 (95% CI, 0.95-0.99)]. This gene signature was validated in a publicly available database. The gene signature outperformed previously identified sepsis biomarkers including C-reactive protein [aROC 0.72 (95% CI, 0.57-0.87)], NT-Pro B-type Natriuretic Peptide [aROC 0.84 (95% CI, 0.73-0.96)], and Septicyte™ LAB [aROC 0.8 (95% CI, 0.68-0.93)], but was comparable to Procalcitonin [aROC 0.96 (95% CI, 0.9-1)].

CONCLUSIONS

A gene expression signature was identified that accurately discriminates between sepsis and aseptic inflammation in patients given antibiotics in the intensive care unit.

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.

Procalcitonin kinetics early after severe burn injury and its value in diagnosis of sepsis

PURPOSE

To investigate the clinical significance of procalcitonin (PCT) kinetics early after burn and the perioperative period, and to assess its diagnostic performance for sepsis in major burn patients.

METHODS

This retrospective study on major burn patents (≥40% total body surface area) admitted from 2014 to 2019 was conducted in Southwest Hospital, Chongqing, China. A total of 321 patients were included. The kinetics of PCT was analyzed during the 1st week after burn, the perioperative period, and at the onset of clinical suspected sepsis.

RESULTS

Serum PCT concentration rose immediately after burn injury. Factors associated with increased PCT level in the 1st week after burn include greater burn area (>70% TBSA) and lower age (≤14 years). Correlations between PCT kinetics after burn and the risk of early development of sepsis and mortality were observed. At the onset of sepsis, serum PCT increased significantly compared to its basal level in the 48 h before diagnosis. The area under the receiver operating characteristics curve of PCT concentration and its kinetic changes was 0.788 and 0.826, respectively. PCT kinetics showed better accuracy than PCT concentration in discrimination of Gram-positive sepsis. The optimal diagnostic thresholds for PCT concentration and its kinetics were 1.41 ng/mL, and a 1.34-fold elevation compared to the baseline level.

CONCLUSIONS

PCT kinetics in the early stage after burn was a prognostic factor for sepsis and mortality among major burn patients. Serum PCT levels could be a diagnostic biomarker for sepsis in major burn patients.

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.

N-Terminal Brain Natriuretic Peptide First Week After Burn Injury

B-type natriuretic peptide has shown promising results as a biomarker for acute kidney injury in general intensive care patients. It may also indirectly reflect fluid balance of the circulation. Among burn patients, it has been observed to indicate excessive fluid resuscitation and organ dysfunction, although its clinical use to indicate acute kidney injury or guide fluid resuscitation has not been validated. The aim of this study was to evaluate whether the N-terminal pro-brain natriuretic peptide values are related to the amount of fluids given after severe burn injury and whether it can act as a novel biomarker for acute kidney injury in these patients. Nineteen consecutive burn patients were included. Plasma N-terminal pro-brain natriuretic peptide was measured daily during 1 week from admission. Other variables such as laboratory values and intravenous infusions were also recorded. The association between acute kidney injury and N-terminal pro-brain natriuretic peptide values was analyzed with a multivariable panel regression model, adjusted for burned total body surface area, age, body mass index, and laboratory values. N-terminal pro-brain natriuretic peptide values varied between single patients, and even more between the patients who developed acute kidney injury. Older age, lower body mass index, and cumulative infusions were independently associated with higher N-terminal pro-brain natriuretic peptide values, whereas acute kidney injury was not. N-terminal pro-brain natriuretic peptide values correlated with cumulative infusions given during the first week. The authors could not validate the role of N-terminal pro-brain natriuretic peptide as a biomarker for acute kidney injury in burns.

A Critical Update of the Assessment and Acute Management of Patients with Severe Burns

Significance: Burns are debilitating, life threatening, and difficult to assess and manage. Recent advances in assessment and management have occurred since a comprehensive review of the care of patients with severe burns was last published, which may influence research and clinical practice. Recent Advances: Recent advances have occurred in the understanding of burn pathophysiology, which has led to the identification of potential biomarkers of burn severity, such as protein C. There is new evidence about the potential superiority of natural colloids over crystalloids during fluid resuscitation, and new evidence about components of initial and perioperative management, including an improved understanding of pain following burns. Critical Issues: The limitations of the clinical examination highlight the need for imaging and biomarkers to assist in estimations of burn severity. Fluid resuscitation reduces mortality, although there is conjecture over the ideal method. The subsequent perioperative period is associated with significant morbidity and the evidence for preventing and treating pain, infection, and fluid overload while maximizing wound healing potential is described. Future Directions: Promising developments are ongoing in imaging technology, histopathology, biomarkers, and wound healing adjuncts such as hyperbaric oxygen therapy, topical negative pressure therapy, stem cell treatments, and skin substitutes. The greatest benefit from further research on management of patients with burns would most likely be derived from the elucidation of optimal fluid resuscitation protocols, pain management protocols, and surgical techniques from randomized controlled trials.

Impact of oral resuscitation on circulating and splenic leukocytes after burns

BACKGROUND

Hemodynamic aberrations after severe burns are treated with aggressive intravenous (IV) fluid resuscitation however, oral resuscitation has been proposed in resource poor scenarios. Previously we have shown that animals receiving oral fluid following burns were able to recover kidney function. However, immune function such as circulating and splenic immune cell populations after oral or intravenous fluid administration was not examined. Herein, we perform a follow up analysis of splenic tissue and plasma from the previous animal study to examine the splenic response following these resuscitation strategies after burn injury.

METHODS

Eighteen anesthetized Yorkshire swine receiving 40%TBSA contact burns were randomized to receive either: (1) no fluids (Fluid Restricted; negative control), (2) 70 mL/kg/d Oral Rehydration Salt solution (Oral), or (3) 2 mL/kg/%TBSA/d of lactated Ringer's solution IV. Blood was drawn for blood cell analysis, and CT scans were performed before and 48 h post-burn, at which point spleens were harvested for histological, Western blot, and RT-PCR analyses.

RESULTS

Splenic artery diameter decreased by -0.97 ± 0.14 mm in fluid-restricted animals, while IV led to an increase of 0.68 ± 0.30 mm. No significant differences were detected in white and red pulp. IV fluids reduced the population of splenic monocytes (CD163; P = 0.001) and neutrophils (MPO protein; P = 0.13), as well as cytokines IL-8 (P = 0.003), IFN-γ (P = 0.11) and TNFα (P = 0.05). Additionally, withholding IV fluids consistently decreased the expression of FoxP3, CCR6, and IL17β in spleen, suggesting a shift in T-cell phenotype with IV resuscitation.

CONCLUSIONS

The route of fluid administration has a minor influence on the changes in circulating and splenic leukocytes post-burn in the acute phase. Further research is needed to help guide resuscitation approaches using immunologic markers of splenic function following burns.

Roles of Procalcitonin and N-Terminal Pro-B-Type Natriuretic Peptide in Predicting Catheter-Related Bloodstream Infection in Severe Burn Injury Patients

Objective

To investigate the characteristics of early catheter-related bloodstream infection (CRBSI) in severe burn injury patients induced by a massive aluminum dust explosion.

Methods

Sixty-eight severe burn injury patients experienced a massive dust explosion in Kunshan were included in this study. Patients received central venous catheter placement, arterial catheterization to monitor blood pressure and PiCCO cardiac monitoring, tracheostomy, mechanical ventilation, analgesics and sedation treatment, and fluid resuscitation. Clinical data including age, gender, burn surface area, fluid intake and output, urine temperature, and APACHE II score information were collected from each patient. Ultrasound screening was performed to exclude heart failure, which may lead to the change of NT-proBNP. When CRBSI was suspected, 10 ml central venous blood and peripheral arterial blood were sent for testing. For patients with suspected CRBSI, the level of PCT and NT-proBNP were monitored every day until the infection was controlled.

Results

Among the 68 patients, 29 showed CRBSI. The most common pathogenic bacteria of CRBSI were A. baumannii (39.8%), P. aeruginosa (26.4%), and K. pneumoniae (13.7%). Procalcitonin (PCT) (2.98 ng/ml) and NT-proBNP (355 pg/ml) were significantly associated with CRBSI results. The sensitivity of PCT, NT-proBNP, WBC, and CRP was 94.2%, 89.7%, 88.3%, and 90.5%, respectively (P < 0.05). The area under curve (AUC) of PCT combined with NT-proBNP for prediction of CRBSI was 0.981, and the sensitivity and specificity was 0.812 and 0.857, respectively.

Conclusion

PCT and NT-proBNP combination improves the diagnosis of CRBSI. PCT and NT-proBNP may be alternative candidates for potential prediction of CRBSI in patients with severe injury.

MR-proADM: A New Biomarker for Early Diagnosis of Sepsis in Burned Patients

Mid regional pro-adrenomedullin (MR-proADM) has been used as a marker of sepsis, but its dynamics and role in a burn injury setting has not been tested. In a prospective observational study, we included 42 consecutive patients with >15% TBSA. Daily blood specimens collected over the initial 20 days of treatment were submitted for laboratory analysis of MR-proADM and procalcitonin (PCT) via immunoluminometric sandwich assay (Kryptor, BRAHMS, Berlin, Germany). In patients with an absence of sepsis, an initial increase in MR-proADM and PCT levels was noted post-burn injury, peaking on the second day postadmission and thereafter demonstrated a continued decline in MR-proADM and PCT levels. In those patients who went on to develop sepsis (n = 27, 64.3%), the levels of MR-proADM and PCT were significantly higher (P < .001) on days categorized as septic, than on days categorized as nonseptic. The increase in PCT levels was noted on the first day to be categorized as septic. In contrast, the MR-proADM levels demonstrated an increase one day earlier. The optimal relationship between the specificity and sensitivity of MR-proADM and PCT for the detection of sepsis was an increase of 31% and at least 0.015 nmol/L (area under curve 0.76) or of >39% and at least 0.15 µg/L (area under the curve 0.83), respectively. Burn injury is associated with increased levels of MR-proADM. Subsequent increases may be considered as diagnostic of sepsis onset. In this context, PCT displayed higher specificity and sensitivity, while MR-proADM may be more suitable for the early recognition of sepsis (ClinicalTrials.gov number, NCT01055587).

Role of Procalcitonin in the Management of Infected Patients in the Intensive Care Unit

The combination of molecular pathogen diagnostics and the biomarker procalcitonin (PCT) are changing the use of antimicrobials in patients admitted to critical care units with severe community-acquired pneumonia, possible septic shock, or other clinical syndromes. An elevated serum PCT level is good supportive evidence of a bacterial pneumonia, whereas a low serum PCT level virtually eliminates an etiologic role for bacteria even if the culture for a potential bacterial pathogen is positive. Serum PCT levels can be increased in any shocklike state; a low PCT level eliminates invasive bacterial infection as an etiology in more than 90% of patients.

Ubiquitin Urine Levels in Burn Patients

The objective of this study was to determine whether urine ubiquitin levels are elevated after burns and to assess whether urine ubiquitin could be useful as a noninvasive biomarker for burn patients. Forty burn patients (%TBSA: 20 ± 22; modified Baux scores: 73 ± 26) were included (control: 11 volunteers). Urine was collected in 2-hour intervals for 72 hours, followed by 12-hour intervals until discharge from the intensive care unit. Ubiquitin concentrations were analyzed by enzyme linked immunosorbent assay and Western blot. Total protein was determined with a Bradford assay. Patient characteristics and clinical parameters were documented. Urine ubiquitin concentrations, renal ubiquitin excretion, and excretion rates were correlated with patient characteristics and outcomes. Initial urine ubiquitin concentrations were 362 ± 575 ng/ml in patients and 14 ± 18 ng/ml in volunteers (P < .01). Renal ubiquitin excretion on day 1 was 292.6 ± 510.8 μg/24 hr and 21 ± 27 μg/24 hr in volunteers (P < .01). Initial ubiquitin concentrations correlated with modified Baux scores (r = .46; P = .02). Ubiquitin levels peaked at day 6 postburn, whereas total protein concentrations and serum creatinine levels remained within the normal range. Total renal ubiquitin excretion and excretion rates were higher in patients with %TBSA ≥20 than with %TBSA <20, in patients who developed sepsis/multiple organ failure than in patients without these complications and in nonsurvivors vs survivors. These data suggest that ubiquitin urine levels are significantly increased after burns. Renal ubiquitin excretion and/or excretion rates are associated with %TBSA, sepsis/multiple organ failure, and mortality. Although these findings may explain previous correlations between systemic ubiquitin levels and outcomes after burns, the large variability of ubiquitin urine levels suggests that urine ubiquitin will not be useful as a noninvasive disease biomarker.

Association of Heart Rate with N-Terminal Pro-B-Type Natriuretic Peptide in Septic Patients: A Prospective Observational Cohort Study

BACKGROUND

Excessive sympathetic stress has multiple adverse effects during critical illness including sepsis. Recent studies showed that heart rate control had a significant effect on reducing mortality in septic shock patients. Furthermore, elevated N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels in septic patients were reportedly associated with adverse outcome. However, no study has evaluated the relationship between hemodynamic profiles of septic patients and the circulating cardiac biomarker. Our objective was to determine whether hemodynamic profiles, specifically tachycardia and new-onset atrial fibrillation (AF), were associated with NT-proBNP elevation in septic patients.

METHODS

We consecutively enrolled patients admitted to our intensive care unit (ICU). NT-proBNP levels, heart rate, and rhythm at ICU admission were measured, and all clinical and laboratory data were prospectively collected. Tachycardia was defined as a heart rate of above 100 bpm.

RESULTS

Ninety-five patients out of 267 patients (35.6%) were diagnosed as sepsis. Of these septic patients, 47 presented with tachycardia and 6 developed new-onset AF. Multivariate Cox regression analysis revealed that tachycardia was an independent predictor of 28-day overall survival in septic patients (hazard ratio, 4.22; 95% confidence interval, 1.10-27.72; P < 0.05), but not in nonseptic patients. Multivariate linear regression analysis demonstrated that the presence of tachycardia was an independent determinant of NT-proBNP elevation (P < 0.05) in septic patients, but not in nonseptic patients.

CONCLUSIONS

Tachycardia was significantly and independently associated with NT-proBNP elevation and lower survival rate in septic patients, although no association was observed in nonseptic patients. Increased NT-proBNP in sepsis with tachycardia might predict poor outcomes in ICU.

Predicting and managing sepsis in burn patients: current perspectives

Modern burn care has led to unprecedented survival rates in burn patients whose injuries were fatal a few decades ago. Along with improved survival, new challenges have emerged in the management of burn patients. Infections top the list of the most common complication after burns, and sepsis is the leading cause of death in both adult and pediatric burn patients. The diagnosis and management of sepsis in burns is complex as a tremendous hypermetabolic response secondary to burn injury can be superimposed on systemic infection, leading to organ dysfunction. The management of a septic burn patient represents a challenging scenario that is commonly encountered by providers caring for burn patients despite preventive efforts. Here, we discuss the current perspectives in the diagnosis and treatment of sepsis and septic shock in burn patients.

Management of Critical Burn Injuries: Recent Developments

Background

Burn injury and its subsequent multisystem effects are commonly encountered by acute care practitioners. Resuscitation is the major component of initial burn care and must be managed to restore and preserve vital organ function. Later complications of burn injury are dominated by infection. Burn centers are often called to manage problems related to thermal injury, including lightning and electrical injuries.

Methods

A selected review is provided of key management concepts as well as of recent reports published by the American Burn Association.

Results

The burn-injured patient is easily and frequently over resuscitated, with ensuing complications that include delayed wound healing and respiratory compromise. A feedback protocol designed to limit the occurrence of excessive resuscitation has been proposed, but no new “gold standard” for resuscitation has replaced the venerated Parkland formula. While new medical therapies have been proposed for patients sustaining inhalation injury, a paradigm-shifting standard of medical therapy has not emerged. Renal failure as a specific contributor to adverse outcome in burns has been reinforced by recent data. Of special problems addressed in burn centers, electrical injuries pose multisystem physiologic challenges and do not fit typical scoring systems.

Conclusion

Recent reports emphasize the dangers of over resuscitation in the setting of burn injury. No new medical therapy for inhalation injury has been generally adopted, but new standards for description of burn-related infections have been presented. The value of the burn center in care of the problems of electrical exposure, both manmade and natural, is demonstrated in recent reports.

The Use of Procalcitonin (PCT) for Diagnosis of Sepsis in Burn Patients: A Meta-Analysis

The continuous development of resuscitation techniques and intensive care reduced the mortality rate induced by the initial shock in burn patients and, currently, infections (especially sepsis) are the main causes of mortality of these patients. The misuse of antimicrobial agents is strongly related to antimicrobial and adverse patient outcomes, development of microbial resistance and increased healthcare-related costs. To overcome these risks, antimicrobial stewardship is mandatory and biomarkers are useful to avoid unnecessary medical prescription, to monitor antimicrobial therapy and to support the decision of its stop. Among a large array of laboratory tests, procalcitonin (PCT) emerged as the leading biomarker to accurately and time-effectively indicate the presence of systemic infection. In the presence of systemic infection, PCT blood levels undergo a sudden and dramatic increase, following the course of the infection, and quickly subside after the control of the septic process. This work is a meta-analysis on PCT performance as a biomarker for sepsis. This meta–analysis showed that overall pooled area under the curve (AUC) is 0.83 (95% CI = 0.76 to 0.90); the estimated cut-off is 1.47 ng/mL. The overall sepsis effect in PCT levels is significant and strong (Cohen's d is 2.1 and 95% CI = 1.1 to 3.2). This meta–analysis showed PCT may be considered as a biomarker with a strong diagnostic ability to discriminate between the septic from the non-septic burn patients. Thus, this work encourages the determination of PCT levels in clinical practice for the management of these patients, in order to timely identify the susceptibility to sepsis and to initiate the antimicrobial therapy, improving the patients’ outcomes.

High-Level Expression of Toll-Like Receptors on Dendritic Cells in Adult Patients with Burns on ≥90% of Total Body Surface Area (TBSA)

Background

As a serious clinical problem, severe burn injury disturbs the immune system, resulting in progressive suppression of immune response. TLRs are associated with immune system activation, but the effect of TLRs levels on circulating cDCs of severe burn injury patients has not been fully assessed.

Material/Methods

Ten patients with total body surface area (TBSA) burned >90% admitted to our institution were enrolled in this study. We analyzed TLR2, TLR4, and TLR9 expression on the circulating cDCs by using multicolor flow cytometric analysis in patients at 14 days to 28 days after burn injury according to mortality, and We also assessed Demographics, clinical outcomes, organ function, and inflammatory and acute-phase responses.

Results

No difference in TBSA, sex, age, or number of operations before the first 14 days after injury were observed between surviving and non-surviving burn patients. The levels of TLR2, TLR4, and TLR9 in circulating cDCs were significantly and consistently elevated in all patients compared to age-matched healthy volunteers, and survivors exhibited higher TLR2 and TLR4 values than non-survivors. Of the survivors, TLR2 and TLR4 levels were higher at 28 days than at 14 days after injury, while the difference in TLR9 levels was not significant. TLR2 levels of non-survivors at 28 days after injury decreased, and the TLR4 and TLR9 levels showed no significant difference.

Conclusions

TLRs levels in circulating cDCs are highly activated in severe burn injury patients up to 28 days after injury. The low expression of TLR2 in cDCs may be useful as a potential marker predicting the poor prognosis of severe burn patients.

Review of Burn Research for Year 2014

Management of burn injuries requires treatments and interventions from many disciplines. Worldwide, burn patients suffer from physical and psychological challenges that impact their lives socially and economically. In this review, we will highlight a handful of the numerous articles published in multiple areas of burn care. The areas of burn care addressed in the article are: epidemiology; burn resuscitation, critical care, and infection; nutrition and metabolism; pain and rehabilitation; prevention and firefighter safety; psychology; and reconstruction and wounds.

Biomarkers in Pediatric Cardiac Critical Care

OBJECTIVES

In this review, we discuss the physiology, pathophysiology, and clinical role of troponin, lactate, and B-type natriuretic peptide in the assessment and management of children with critical cardiac disease.

DATA SOURCE

MEDLINE, PubMed.

CONCLUSION

Lactate, troponin, and B-type natriuretic peptide continue to be valuable biomarkers in the assessment and management of critically ill children with cardiac disease. However, the use of these markers as a single measurement is handicapped by the wide variety of clinical scenarios in which they may be increased. The overall trend may be more useful than any single level with a persistent or rising value of more importance than an elevated initial value.

The use and risks of antibiotics in critically ill patients

INTRODUCTION

The altered pathophysiology in critically ill patients presents a unique challenge in both the diagnosis of infection and the appropriate prescription of antibiotics. In this context, the importance of effective and timely treatment needs to be weighed against the individual and community harms associated with antibiotic collateral damage and antibiotic resistance.

AREAS COVERED

We evaluate the principles of antibiotic use in critically ill patients, including dose optimisation, use of combination antibiotic therapy, therapeutic drug monitoring, appropriate antibiotic therapy duration, de-escalation, and utilisation of sepsis biomarkers. We also describe the potential risks associated with antibiotic therapy including antibiotic resistance, delayed treatment, treatment failure, and collateral damage.

EXPERT OPINION

Prescribing teams must be aware of the impact of critical illness on their patients and tailor antibiotic therapy appropriately to prevent the significant harms associated with suboptimal antibiotic administration.

Brain not processing: is finding a role for BNP in sepsis like fitting a square peg into a round hole?

Since its introduction to the intensive care setting a decade ago, B-type natriuretic peptide has been the focus of studies in different areas (in particular, sepsis). With this biomarker, as with many newly identified biomarkers, its diagnostic performance was pursued initially and then its ability to predict outcomes. Despite all the efforts, results have not been consistent and the applications of B-type natriuretic peptide in the intensive care setting remain by and large academic. Will such studies one day become clinical practice? Or are we too obsessed with finding a place for every biomarker?

Allergic airway inflammation initiates long-term vascular remodeling of the pulmonary circulation

BACKGROUND

Asthma and allergic airway inflammation are associated with persistent structural alterations in the bronchi, i.e. airway remodeling. Previous studies have shown that during allergic airway inflammation, similar structural alterations may also be evoked in the pulmonary circulation. However, it remained unknown whether remodeling of the pulmonary circulation is as persistent as airway remodeling. The aim of this study is to investigate the reversibility and resolution of vascular remodeling, induced by allergic airway inflammation.

METHODS

A validated mouse model of allergic airway inflammation, utilizing ovalbumin as allergen, was employed. Animals were sacrificed 1 day, 1 week or 1 month after the last allergen exposure, and different parameters of remodeling (smooth muscle mass, proliferation of smooth muscle cells and endothelial cells as well as number of myofibroblasts and procollagen-I-producing cells) were investigated and quantified histologically.

RESULTS

Allergen exposure resulted in allergic airway inflammation characterized by a transient leukocyte infiltration and in structural alterations in both airway and vascular compartments. The increase in vascular smooth muscle mass and endothelial proliferation persisted at 1 month after the last allergen exposure. The other parameters and cellular inflammatory response returned to baseline within 1 month after the last allergen challenge.

CONCLUSIONS

Based on the findings in this study, we conclude that acute allergic airway inflammation, although being initiated from the airways, is able to evoke similar long-term structural alterations in pulmonary vessels as described for bronchi.