Acute kidney injury in critically ill burn patients. Risk factors, progression and impact on mortality

Acute kidney injury in pediatric burn patients

BACKGROUND

Acute kidney injury (AKI) is a common and important complication of burn injury. Although there are numerous adult studies, data regarding AKI in pediatric burn patients are scarce. Here, we aimed to evaluate the frequency, clinical features, and prognosis of AKI among pediatric burn injury patients.

METHODS

This is a retrospective cohort study. Patients aged between 1 month and 18 years who had been followed up between the years 2011 and 2017 were included, and patients with previous kidney disease were excluded. Demographic data, laboratory and clinical variables, management strategies, and outcome data were obtained from the hospital records. Factors associated with AKI were determined by logistic regression analysis.

RESULTS

A total of 697 patients had been followed up, and 87 (12.5%) had AKI. Older age, refugee status, prolonged duration between the incident and time of hospitalization, presence of sepsis, severity and type of burn, volume of fluid administration, intubation status, and accompanying organ failure were all associated with the development of AKI. According to multivariate logistic regression analysis, the most statistically significant factors associated with the development of AKI were older age and increased serum hemoglobin values. In terms of outcomes, length of stay and mortality increased in patients with AKI when compared with patients without AKI.

CONCLUSION

Similar to adults, AKI is an important and common complication of burn injury in pediatric burn patients and is associated with increased length of stay, morbidity, and mortality. Early recognition and prompt and appropriate management are crucial to avoid morbidity and mortality.

Huangqi Jiuni decoction prevents acute kidney injury induced by severe burns by inhibiting activation of the TNF/NF-κB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Huangqi Jiuni decoction (HQJND) is a prescription for the treatment of severe burns provided based on traditional Chinese and Western medicine, which is created by the First Affiliated Hospital of Anhui Medical University. It consists of 12 herbs and has been used clinically for decades. It has greatly shortened the course of the disease, but the mechanism by which HQJND treats the disease still remains unclear.

AIM OF THE STUDY

Hence, the objective of this investigation was to utilize modern pharmacological tools to demonstrate the efficacy and mechanism of HQJND in the treatment of acute kidney injury (AKI) caused by severe burns.

MATERIALS AND METHODS

In this study, the chemical constituents in HQJND were first examined using liquid chromatography tandem mass spectrometry (LC-MS/MS). Then, by using network pharmacology, we screened the targets of drug and disease action, and predicted the signaling pathways acting in the course of drug treatment of disease. Finally, we attempted to verify the efficacy of the drug and explored its therapeutic mechanism after the establishment of an animal model, herbal gavage treatment, collection of rat kidneys and serum for renal function, quantitative real-time Polymerase Chain Reaction (RT-qPCR), Western Blotting (WB), Hematoxylin and eosin (HE) staining and Immunohistochemistry (IHC).

RESULTS

The 14 important active ingredients in HQJND was analyzed by liquid chromatography tandem mass spectrometry, while network pharmacology screening was performed to identify 353 disease-associated marker genes and 286 drug targets, finally identifying the TNF/NF-κB (tumor necrosis factor/nuclear factor kappa-B) signaling site: the key pathway of burn-induced acute kidney injury when HQJND intervened. The serum renal function and histopathology of rats demonstrated that the use of HQJND significantly improved the renal function in severe burns. RT-qPCR and WB confirmed that the TNF/NF-κB signaling pathway was activated in the Model group of rats, and HQJND could curb the signaling pathway because it moderated the expressions of key proteins in the process.

CONCLUSION

Based on modern pharmacology, we explored an effective herbal preparation to ameliorate the impairment of renal function after severe burns, which is most likely to function through the TNF/NF-κB signaling pathway.

Nephrotoxic drug burden and predictors of exposure among patients with renal impairment in Ethiopia: A multi-center study

Background

Nephrotoxic drugs may hasten the decline in kidney function and worsen the progression of renal impairment as a result; these drugs should be avoided or used with caution in patients with pre-existing renal insufficiency. The purpose of this study was to assess the burden of nephrotoxic medication use and its predictors among patients with underlying renal impairment.

Methods

A multicenter, institution-based, cross-sectional study was conducted from May 30, 2021 to July 30, 2021, at medical wards. Renal impaired patients admitted during the data collection period who took at least one medication were enrolled in the study. A simple random sampling technique was used to select the study participants. Data was collected through an interview and a medical card review. Both bivariable and multivariable binary logistic regression analyses were fitted to identify factors associated with nephrotoxic drug use.

Results

Among the 422 participants, more than half of them (53.6 %) were male. The mean patient's age was 47.5 (±16.7) years. A total of 1310 drugs were prescribed for 422 patients with renal impairment, of which 80.15 % were nephrotoxic. Nephrotoxic drugs were prescribed for 66.4 % of patients. The burden of nephrotoxic medication prescription was significantly associated with variables like the presence of comorbidity (AOR = 6.31, 95 % CI: 2.01-19.79), the number of medications prescribed (AOR = 1.43, 95 % CI: 1.05-1.93), and the age of participants (AOR = 1.12, 95 % CI: 1.07-1.17).

Conclusion

The present study demonstrated that two-third of the patients with renal impairment were exposed to nephrotoxic medications. Furosemide, Enalapril, and vancomycin were the most frequently prescribed nephrotoxic medications. The study suggests that prescribers need to give special attention to older patients who have underlying renal insufficiency, a comorbid condition, and polypharmacy regarding exposure to contraindicated nephrotoxic medication.

Early acute kidney injury is associated with in-hospital adverse outcomes in critically ill burn patients: an observational study

BACKGROUND

There are no studies in large series of burn patients on the relationship between acute kidney injury (AKI) and adverse outcomes using the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines.

METHODS

We retrospectively analysed data from a cohort of burn patients admitted to the intensive care unit (ICU) with the diagnosis of burn injury. The diagnosis of AKI over the first 7 days after injury was made according to the KDIGO guidelines. The primary outcome was ICU mortality. We used estimative models using univariable and multivariable logistic regression analyses.

RESULTS

A total of 960 patients were studied and AKI was diagnosed in 50.5%. In multivariable analysis, AKI was associated, as compared with patients without AKI, with ICU mortality {adjusted odds ratio [aOR] 2.135 [95% confidence interval (CI) 1.384-3.293]} and secondary outcomes [kidney replacement therapy, aOR 4.030 (95% CI 1.838-8.835); infection, aOR 1.437 (95% CI 1.107-1.866); hospital mortality, aOR 1.652 (95% CI 1.139-2.697)]. AKI stage 1 was associated with a higher ICU [aOR 1.869 (95% CI 1.183-2.954)] and hospital mortality [aOR 1.552 (95% CI 1.050-2.296)] and infection [aOR 1.383 (95% CI 1.049-1.823)]. AKI meeting the urine output (UO) criterion alone was not associated with increased mortality. Ignoring the UO criterion would have missed 50 (10.3%) cases with AKI.

CONCLUSION

The KDIGO guidelines are useful to diagnose AKI in burn patients. Even the mild form of AKI is independently associated with increased mortality. Considering the UO criterion is important to more accurately assess the incidence of AKI, but AKI meeting the UO criterion alone is not associated with increased mortality.

Exploring the Past to Inform the Future to Optimize the Pharmacokinetics of Vancomycin in Children With Severe Burn Injuries

Sepsis remains one of the leading causes of death among pediatric patients with burn injuries. Despite limited vancomycin pharmacokinetic (PK) information within this population, it is widely used to treat severe burn injuries. Those with severe burns are at risk of nephrotoxicity, with an incidence of acute kidney injury (AKI) over 50%. Delivering an effective vancomycin dose and avoiding unnecessary toxicity is essential for improved patient outcomes. This was a retrospective analysis of 115 children aged 0.2 months to 18 years with severe burns, >10% total body surface area. Vancomycin was given via intravenous infusion; blood samples were drawn between 6- and 12-hour postinfusion. A population pharmacokinetic model was developed using nonlinear mixed-effect modeling (Monolix, version 2016R1). A one-compartment model described a steady-state volume of distribution (V), dependent on weight. Vancomycin clearance (CL) was influenced by age and estimated creatinine clearance (CrCL). The study population's (median age = 4 years, median weight = 20 kg, median total body surface area (%TBSA) = 40%) median V and CL were calculated to be 1.25 L/kg (95% CI, 1.04-1.46) and 0.15 L/h/kg (95% CI, 0.126-0.165), respectively. The PK model was explicitly developed to characterize the impact of physiological changes in children under 18 years of age and the percentage of the burn surface area using limited data. The analysis determined that weight, age, and estimated CrCL were important covariates in predicting vancomycin PK with high variability in CL and V.

Optimizing the timing of renal replacement therapy in burn patients with acute kidney injury

Acute kidney injury is a common complication in burn ICU patients and is associated with a high mortality rate. The optimal timing for starting renal replacement therapy (RRT) remains unknown; there is no established universal definition for early and late RRT initiation. The aims of the present narrative review are to briefly analyze the available recently published data on the timing of initiation of RRT in critically ill patients and to discuss the optimal timing of RRT in critically ill burn patients with acute kidney injury. When considering renal replacement therapy for acute kidney injury patients, physicians face the dilemma of balancing the hazards of starting too early, exposing patient to an unnecessary therapy with possible complications and costs related to treatment, and preventing a significant proportion of patients from spontaneous recovery of their renal function against the potential life-threatening harm of initiating RRT) too late. Evidence suggests that with appropriate care up to 80% of burn patients experience recovery of kidney function and the need for RRT seems to be very rare after hospital discharge. In the absence of life-threatening complications, the optimal time and thresholds for starting RRT in burn patients are uncertain. High heterogeneity exists between studies on RRT timing in burn patients.

Burn-Induced Acute Kidney Injury-Two-Lane Road: From Molecular to Clinical Aspects

Severe burn injuries lead to acute kidney injury (AKI) development, increasing the mortality risk up to 28-100%. In addition, there is an increase in hospitalization days and complications appearance. Various factors are responsible for acute or late AKI debut, like hypovolemia, important inflammatory response, excessive load of denatured proteins, sepsis, and severe organic dysfunction. The main measure to improve the prognosis of these patients is rapidly recognizing this condition and reversing the underlying events. For this reason, different renal biomarkers have been studied over the years for early identification of burn-induced AKI, like neutrophil gelatinase-associated lipocalin (NGAL), cystatin C, kidney injury molecule-1 (KIM-1), tissue inhibitor of metalloproteinase-2 (TIMP-2), interleukin-18 (IL-18), and insulin-like growth factor-binding protein 7 (IGFBP7). The fundamental purpose of these studies is to find a way to recognize and prevent acute renal injury progression early in order to decrease the risk of mortality and chronic kidney disease (CKD) onset.

Renal replacement therapy for acute kidney injury in burn patients, an international survey and a qualitative review of current controversies

BACKGROUND OF THE STUDY

Acute kidney injury (AKI) is a common complication in critically ill burn patients and is associated with a number of serious adverse outcomes. The clinical decision-making process related to the management of AKI in burn patients is complex and has not been sufficiently standardized. The main aim of this study was to explore the diagnostic approach and clinician's attitudes toward the management of AKI and RRT in burn patients around the world.

METHODS

The questionnaire was widely distributed among the members of International Society for Burn Injury (ISBI), who were invited to complete the survey. Data collection and report was compliant with the the Checklist for Reporting Results of Internet E-Surveys (CHERRIES) Web-survey guidelines. The survey form with multiple-choice questions was divided into 3 parts: a. physician and institutional demographics, b. AKI diagnostic information, c. technical aspects of RRT.

RESULTS

A total of 44 respondents worldwide submitted valuable data in the 2-month period. Of all respondents, 43.2% were from Europe, 30% from North America, 7% from South-East Asia 2.3% from Africa and 18.2% from other regions. 93.1% of participants declare that they use specific definitions to detect AKI, while 11.4% declare the use of renal ultrasonography for AKI diagnosis. CRRT appeared to be the most preferred option by 43.2% of participants, followed by intermittent hemodialysis (25%), and prolonged intermittent RRT (6.8%). The expertise to deliver a modality and the availability of resources were considered important factors when selecting the optimal RRT modality by 20.5% and 29.6% of respondents. The use of specific serum biomarkers for AKI diagnosis are stated by 16% of respondents; 25% of specialists refer to the use of biomarkers of AKI as a criterium for discontinuing the RRT. Femoral vena and right jugular vena were the most frequently used location for RRT temporary catheter placement, 54.6% of respondents declared using ultrasound guidance for catheter placement.

CONCLUSIONS

The majority of burn specialists use specific consensus classifications to detect acute kidney injury. Continuous renal replacement therapy appeared to be the most preferred option, while the expertise to deliver a particular modality and resources availability play a significant role in modality selection. The use of ultrasound and specific biomarkers for AKI evaluation is infrequent in routine clinical practice.

Late-Onset Acute Kidney Injury is a Poor Prognostic Sign for Severe Burn Patients

Background

Acute kidney injury (AKI) is a morbid complication and the main cause of multiple organ failure and death in severely burned patients. The objective of this study was to explore epidemiology, risk factors, and outcomes of AKI for severely burned patients.

Methods

This retrospective study was performed with prospectively collected data of severely burned patients from the Institute of Burn Research in Southwest Hospital during 2011–2017. AKI was diagnosed according to Kidney Disease Improving Global Outcomes (KDIGO) criteria (2012), and it was divided into early and late AKIs depending on its onset time (within the first 3 days or >3 days post burn). The baseline characteristics, clinical data, and outcomes of the three groups (early AKI, late AKI and non-AKI) were compared using logistic regression analysis. Mortality predictors of patients with AKI were assessed.

Results

A total of 637 adult patients were included in analysis. The incidence of AKI was 36.9% (early AKI 29.4%, late AKI 10.0%). Multiple logistic regression analysis revealed that age, gender, total burn surface area (TBSA), full-thickness burns of TBSA, chronic comorbidities (hypertension or/and diabetes), hypovolemic shock of early burn, and tracheotomy were independent risk factors for both early and late AKIs. However, sepsis was only an independent risk factor for late AKI. Decompression escharotomy was a protective factor for both AKIs. The mortality of patients with AKI was 32.3% (early AKI 25.7%, late AKI 56.3%), and that of patients without AKI was 2.5%. AKI was independently associated with obviously increased mortality of severely burned patients [early AKI, OR = 12.98 (6.08–27.72); late AKI, OR = 34.02 (15.69–73.75)]. Compared with patients with early AKI, patients with late AKI had higher 28-day mortality (34.9% vs. 19.4%, p = 0.007), 90-day mortality (57.1% vs. 27.4%, p < 0.0001).

Conclusions

AKI remains prevalent and is associated with high mortality in severely burned patients. Late-onset acute kidney injury had greater severity and worse prognosis.

Colistin Therapy, Survival and Renal Replacement Therapy in Burn Patients: A 10-Year Single-Center Cohort Study

Purpose

Patients and Methods

Results

Conclusion

An Early Warning System for the Differential Diagnosis of In-Hospital Acute Kidney Injury for Better Patient Outcome: Study of a Quality Improvement Initiative

Background: Acute kidney injury (AKI) is a syndrome with heterogeneous causes and mechanisms. An early warning system (EWS) for AKI was created to reduce the incidence and improve outcomes. However, the benefits of AKI-EWS remain debatable. Methods: We launched a project to design and create AKI-EWS for inpatients in our institute. Incidence of AKI and its outcome before and after the implementation of AKI-EWS were collected for analysis. Results: We enlisted a stakeholder map before creating AKI-EWS. We then started an action plan for this initiative. The diagnosis was automatic and based on the definition of Kidney Disease: Improving Global Outcomes (KDIGO). The differential diagnosis of causes of AKI was also automatic. Users are to adjust the threshold of detection. After the implementation of this AKI-EWS, the incidence of AKI fell. The proportion of AKI > 4% was reduced significantly (47.7% and 41.6%, p = 0.010) in patients with serum creatinine measured. The proportion of AKI > 0.9% also dropped significantly (51.67% and 35.94%, p = 0.024) in all inpatients. Trends of AKI outcomes also showed improvement. The loading of consultation of nephrologists decreased by 15.5%. Conclusions: Through well-designed AKI-EWS, the incidence of AKI dropped, showing improved outcomes. The factors affecting benefits from AKI-EWS included high-risk identification (individual threshold detection), timely and automatic diagnosis, real-time alerting on electronic health information systems, fast self-diagnosing of the cause of AKI, and coverage of all inpatients.

Hypoxia-Inducible Factors and Burn-Associated Acute Kidney Injury-A New Paradigm?

O₂ deprivation induces stress in living cells linked to free-radical accumulation and oxidative stress (OS) development. Hypoxia is established when the overall oxygen pressure is less than 40 mmHg in cells or tissues. However, tissues and cells have different degrees of hypoxia. Hypoxia or low O₂ tension may be present in both physiological (during embryonic development) and pathological circumstances (ischemia, wound healing, and cancer). Meanwhile, the kidneys are major energy-consuming organs, being second only to the heart, with an increased mitochondrial content and O₂ consumption. Furthermore, hypoxia-inducible factors (HIFs) are the key players that orchestrate the mammalian response to hypoxia. HIFs adapt cells to low oxygen concentrations by regulating transcriptional programs involved in erythropoiesis, angiogenesis, and metabolism. On the other hand, one of the life-threatening complications of severe burns is acute kidney injury (AKI). The dreaded functional consequence of AKI is an acute decline in renal function. Taking all these aspects into consideration, the aim of this review is to describe the role and underline the importance of HIFs in the development of AKI in patients with severe burns, because kidney hypoxia is constant in the presence of severe burns, and HIFs are major players in the adaptative response of all tissues to hypoxia.

Small animal models of thermal injury

Burns are a severe form of trauma that account for 1.1 million cases necessitating medical attention and 4500 mortalities annually in the United States alone. Importantly, the initial trauma is succeeded by extensive, prolonged physiological alterations that detrimentally impact multiple organ systems. Given the complexity of post-burn pathophysiology, in vitro experiments are insufficient to model thermal injuries. Therefore, compatible animal burn models are essential for studying burn-related phenomena. In this chapter, we discuss commonly employed small animal burn models and their comparability and applicability to human studies. In particular, we compare post-burn wound healing between the species as well as relevant hypermetabolic and inflammatory characteristics, providing a better understanding of the pros and cons of utilizing a small animal surrogate for human burns. We further provide an overview of the rodent scald burn model methodology as well as a comparison between elderly, aged and young animals, providing a guide for tailoring animal model choice based on the relevant research question.

Continuous renal replacement therapy under special conditions like sepsis, burn, cardiac failure, neurotrauma, and liver failure

Continuous renal replacement therapy (CRRT) in sepsis does have a role in removing excessive fluid, and also role in removal of mediators although not proven today, and to allow fluid space in order to feed. In these conditions, continuous renal replacement therapy can improve morbidity but never mortality so far. Regarding sepsis, timing has become a more important issue after decades and is currently more discussed than dosing. Rationale of blood purification has evolved a lot in the last years regarding sepsis with the discovery of many types of sorbent allowing ideas from science fiction to become reality in 2021. Undoubtedly, COVID-19 has reactivated the interest of blood purification in sepsis but also in COVID-19. Burn is even more dependent about removal of excessive fluid as compared to sepsis. Regarding cardiac failure, ultrafiltration can improve the quality of life and morbidity when diuretics are becoming inefficient but can never improve mortality. Regarding brain injury, CRRTs have several advantages as compared to intermittent hemodialysis. In liver failure, there have been no randomized controlled trials to examine whether single-pass albumin dialysis offers advantages over standard supportive care, and there is always the cost of albumin.

Incidence, risk factors and outcome of acute kidney injury (AKI) in patients with COVID-19

Background

Acute kidney injury (AKI) is a severe complication of coronavirus disease-2019 (COVID-19). This study aims to evaluate incidence, risk factors and case-fatality rate of AKI in patients with COVID-19.

Methods

We reviewed the health medical records of 307 consecutive patients with COVID-19 hospitalized at the University Hospital of Modena, Italy.

Results

AKI was diagnosed in 69 out of 307 (22.4%) COVID-19 patients. Stages 1, 2, or 3 AKI accounted for 57.9%, 24.6% and 17.3%, respectively. AKI patients had a mean age of 74.7 ± 9.9 years. These patients showed higher serum levels of the main markers of inflammation and higher rate of severe pneumonia than non-AKI patients. Kidney injury was associated with a higher rate of urinary abnormalities including proteinuria (0.44 ± 0.85 vs 0.18 ± 0.29 mg/mg; P =  < 0.0001) and microscopic hematuria (P = 0.032) compared to non-AKI patients. Hemodialysis was performed in 7.2% of the subjects and 33.3% of the survivors did not recover kidney function after AKI. Risk factors for kidney injury were age, male sex, CKD and higher non-renal SOFA score. Patients with AKI had a mortality rate of 56.5%. Adjusted Cox regression analysis revealed that COVID-19-associated AKI was independently associated with in-hospital death (hazard ratio [HR] = 4.82; CI 95%, 1.36–17.08) compared to non-AKI patients.

Conclusion

AKI was a common and harmful consequence of COVID-19. It manifested with urinary abnormalities (proteinuria, microscopic hematuria) and conferred an increased risk for death. Given the well-known short-term sequelae of AKI, prevention of kidney injury is imperative in this vulnerable cohort of patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10157-021-02092-x.

Enhancing Military Burn- and Trauma-Related Acute Kidney Injury Prediction Through an Automated Machine Learning Platform and Point-of-Care Testing

CONTEXT.—

Delayed recognition of acute kidney injury (AKI) results in poor outcomes in military and civilian burn-trauma care. Poor predictive ability of urine output (UOP) and creatinine contribute to the delayed recognition of AKI.

OBJECTIVE.—

To determine the impact of point-of-care (POC) AKI biomarker enhanced by machine learning (ML) algorithms in burn-injured and trauma patients.

DESIGN.—

We conducted a 2-phased study to develop and validate a novel POC device for measuring neutrophil gelatinase-associated lipocalin (NGAL) and creatinine from blood samples. In phase I, 40 remnant plasma samples were used to evaluate the analytic performance of the POC device. Next, phase II enrolled 125 adults with either burns that were 20% or greater of total body surface area or nonburn trauma with suspicion of AKI for clinical validation. We applied an automated ML approach to develop models predicting AKI, using a combination of NGAL, creatinine, and/or UOP as features.

RESULTS.—

Point-of-care NGAL (mean [SD] bias: 9.8 [38.5] ng/mL, P = .10) and creatinine results (mean [SD] bias: 0.28 [0.30] mg/dL, P = .18) were comparable to the reference method. NGAL was an independent predictor of AKI (odds ratio, 1.6; 95% CI, 0.08-5.20; P = .01). The optimal ML model achieved an accuracy, sensitivity, and specificity of 96%, 92.3%, and 97.7%, respectively, with NGAL, creatinine, and UOP as features. Area under the receiver operator curve was 0.96.

CONCLUSIONS.—

Point-of-care NGAL testing is feasible and produces results comparable to reference methods. Machine learning enhanced the predictive performance of AKI biomarkers including NGAL and was superior to the current techniques.

Early Acute Kidney Injury Following Major Burns

Acute kidney injury (AKI) early after a major burn has not been widely studied. Our purpose was to evaluate the prevalence of and risk factors for early AKI and the effect of early AKI on outcome. Retrospective cohort study of adults with burns ≥20% TBSA admitted between November 24, 2015 and July 1, 2019. "Early AKI" occurring within 7 days of injury was identified using urine output and serum creatinine Kidney Disease International Global Outcome criteria. Multivariate regression models were developed for development of early AKI, development of AKI on day 0 or 1 postburn ("very early AKI"), and for in-hospital death. Among 85 patients, 62.4% developed early AKI, of which 26% had stage 3 AKI. Renal replacement therapy was required in 64% of stage 3 patients by day 7. Patients with early AKI were significantly older [50 (40.5-61) vs 37.5 (27.2-46.8) years, P < .001], and a significantly greater proportion was intubated in the first 24 hours postburn (90.6 vs 59.4%, P = .001). Resuscitation with high-dose vitamin C (HDVC) was independently associated with more frequent early AKI. Older age was significantly associated and HDVC was closely associated with increased very early AKI. In-hospital mortality was 37.7% for patients with early AKI. Older age, larger burn size, and development of early stage 3 AKI were independently associated with increased in-hospital death. Early AKI is common and carries a poor prognosis for survival. Resuscitation involving HDVC appears to be related to a higher likelihood of early and possibly very early AKI.

Factors Impacting Survival in Patients With Major Burn-Induced Acute Kidney Injury Postrenal Replacement Therapy: A Nationwide Study With 15 Years Follow-Up in Taiwan

BACKGROUND

Major burn-induced acute kidney injury (AKI) causes extremely high mortality, even though renal replacement therapy (RRT) was thought of as the most efficient treatment. There was scanty research for investigating the characteristic of burn-AKI-RRT patients during intensive care. This study aims to investigate the factors impacting the survival outcomes in those burn-AKI-RRT cases.

METHODS

Using the Taiwan National Health Insurance Research Database and its affiliated database, the Registry for Catastrophic Illness Patients, we defined a cohort composed of 171 patients encountering major burn-induced AKI and receiving RRT during burn care for a 15-year observation period. Demographic characteristic, comorbidities, total body surface area (TBSA), major procedures, and complications were analyzed to explore the factors affecting the survival outcomes during acute burn care and 1 year after discharge.

RESULTS

Patients who underwent tracheostomy and skin grafting had higher survival rates during acute burn care (tracheostomy: mortality vs survival, 15.7% vs 30.2%; P = 0.0257; skin grafting: mortality vs survival, 57.4% vs 76.2%; P = 0.0134). Multivariate regression analysis showed that tracheostomy group significantly presented with lower mortality risk by 65% (odds ratio [OR], 0.35; P = 0.0372), and subgroup analysis of delaminating follow-up duration showed that patients with tracheostomy had higher overall survival by 22% (90-day postburn mortality: nontracheostomy vs tracheostomy, 58.3% vs 36.3%; adjusted hazards ratio, 0.39; 95% confidence interval, 0.22-0.69; P = 0.0011), especially during postburn first 30 days (adjusted hazards ratio, 0.15; 95% confidence interval, 0.05-0.49; P = 0.0016). Total body surface area did not significantly affect survival; however, mortality risk was significantly higher in those with a larger TBSA (TBSA, ≥80%; OR, 6.48; P = 0.0022; TBSA, 60-79%; OR, 3.12; P = 0.0518; TBSA, 40-59%; OR, 1.88; P = 0.2402; TBSA, 30-39% as reference).

CONCLUSIONS

For patients with major burn-induced AKI receiving RRT, tracheostomy and skin grafting may improve survival in the cases living through acute burn stage.

Locally activated mitophagy contributes to a "built-in" protection against early burn-wound progression in rats

AIMS

Deep burn-wounds undergo a dynamic progression in the initial or periburn area after insults, and the zone of stasis is the crucial region suffering the deterioration, considered as salvageable. Few studies explored the role of mitochondria in this process. This study is to clarify a possible "built-in" protection of mitophagy.

MAIN METHODS

A classic "comb" scald rat model was established. Histological and blood-flow observation were processed based on hematoxylin-eosin staining and laser analysis. Oxidative and apoptotic status were analyzed by commercial kits. Transmission-electron microscope, immunofluorescence staining, and western blot were applied to detect the mitophagy in the zone of stasis and potential regulators. Adenovirus-based gene-silence contributed to determine the role of HIF-1α as a regulatory mediator.

KEY FINDINGS

We found that burn-caused typical ischemia and histological deterioration in the zone of stasis, in parallel with increases in oxidative stress and apoptosis. Mitochondrial damage was involved in the aforementioned changes. Furthermore, we detected mitophagy in burn-wounds, which was contradictory to the burn-wound conversion. HIF-1α expression was closely related to the level of mitophagy, while BNIP3 and PARKIN are involved downstream.

SIGNIFICANCE

We demonstrate that burn-induced mitochondrial impairment contributes to the mobilization of injurious mechanisms in the zone of stasis and that mitophagy provides a beneficial way to protect against burn-wound progression via the elimination of damaged mitochondria. Our findings offer insights into mitochondrial quality control in burn-wound progression and suggest the novel concept that HIF-1α may be a therapeutic target due to its possible regulation on BNIP3- or PARKIN-mediated mitophagy.

Recognition and management of community-acquired acute kidney injury in low-resource settings in the ISN 0by25 trial: A multi-country feasibility study

BACKGROUND

Acute kidney injury (AKI) is increasingly encountered in community settings and contributes to morbidity, mortality, and increased resource utilization worldwide. In low-resource settings, lack of awareness of and limited access to diagnostic and therapeutic interventions likely influence patient management. We evaluated the feasibility of the use of point-of-care (POC) serum creatinine and urine dipstick testing with an education and training program to optimize the identification and management of AKI in the community in 3 low-resource countries.

METHODS AND FINDINGS

Patients presenting to healthcare centers (HCCs) from 1 October 2016 to 29 September 2017 in the cities Cochabamba, Bolivia; Dharan, Nepal; and Blantyre, Malawi, were assessed utilizing a symptom-based risk score to identify patients at moderate to high AKI risk. POC testing for serum creatinine and urine dipstick at enrollment were utilized to classify these patients as having chronic kidney disease (CKD), acute kidney disease (AKD), or no kidney disease (NKD). Patients were followed for a maximum of 6 months with repeat POC testing. AKI development was assessed at 7 days, kidney recovery at 1 month, and progression to CKD and mortality at 3 and 6 months. Following an observation phase to establish baseline data, care providers and physicians in the HCCs were trained with a standardized protocol utilizing POC tests to evaluate and manage patients, guided by physicians in referral hospitals connected via mobile digital technology. We evaluated 3,577 patients, and 2,101 were enrolled: 978 in the observation phase and 1,123 in the intervention phase. Due to the high number of patients attending the centers daily, it was not feasible to screen all patients to assess the actual incidence of AKI. Of enrolled patients, 1,825/2,101 (87%) were adults, 1,117/2,101 (53%) were females, 399/2,101 (19%) were from Bolivia, 813/2,101 (39%) were from Malawi, and 889/2,101 (42%) were from Nepal. The age of enrolled patients ranged from 1 month to 96 years, with a mean of 43 years (SD 21) and a median of 43 years (IQR 27-62). Hypertension was the most common comorbidity (418/2,101; 20%). At enrollment, 197/2,101 (9.4%) had CKD, and 1,199/2,101 (57%) had AKD. AKI developed in 30% within 7 days. By 1 month, 268/978 (27%) patients in the observation phase and 203/1,123 (18%) in the intervention phase were lost to follow-up. In the intervention phase, more patients received fluids (observation 714/978 [73%] versus intervention 874/1,123 [78%]; 95% CI 0.63, 0.94; p = 0.012), hospitalization was reduced (observation 578/978 [59%] versus intervention 548/1,123 [49%]; 95% CI 0.55, 0.79; p < 0.001), and admitted patients with severe AKI did not show a significantly lower mortality during follow-up (observation 27/135 [20%] versus intervention 21/178 [11.8%]; 95% CI 0.98, 3.52; p = 0.057). Of 504 patients with kidney function assessed during the 6-month follow-up, de novo CKD arose in 79/484 (16.3%), with no difference between the observation and intervention phase (95% CI 0.91, 2.47; p = 0.101). Overall mortality was 273/2,101 (13%) and was highest in those who had CKD (24/106; 23%), followed by those with AKD (128/760; 17%), AKI (85/628; 14%), and NKD (36/607; 6%). The main limitation of our study was the inability to determine the actual incidence of kidney dysfunction in the health centers as it was not feasible to screen all the patients due to the high numbers seen daily.

CONCLUSIONS

This multicenter, non-randomized feasibility study in low-resource settings demonstrates that it is feasible to implement a comprehensive program utilizing POC testing and protocol-based management to improve the recognition and management of AKI and AKD in high-risk patients in primary care.

The incidence, risk factors and prognosis of acute kidney injury in severe and critically ill patients with COVID-19 in mainland China: a retrospective study

BACKGROUND

The clinical correlates, prognosis and determinants of acute kidney injury (AKI) in patients with coronavirus disease 2019 (Covid-19) remain largely unclear.

METHODS

We retrospectively reviewed medical records of all adult patients with laboratory-confirmed Covid-19 who were admitted to the intensive care unit (ICU) between January 23rd 2020 and April 6th 2020 at Wuhan JinYinTan Hospital and The First Affiliated Hospital of Guangzhou Medical University.

RESULTS

Among 210 patients, 131 were males (62.4%). The median Age was 64 years (IQR: 56-71). Of 92 (43.8%) patients who developed AKI during hospitalization, 13 (14.1%), 15 (16.3%) and 64 (69.6%) were classified as being at stage 1, 2 and 3, respectively. 54 patients (58.7%) received continuous renal replacement therapy. Age, sepsis, nephrotoxic drug, invasive mechanical ventilation and elevated baseline serum creatinine levels were associated with the occurrence of AKI. Renal recovery during hospitalization was identified among 16 patients with AKI (17.4%), who had a significantly shorter time from admission to AKI diagnosis, lower incidence of right heart failure and higher ratio of partial pressure of oxygen to the fraction of inspired oxygen. Of 210 patients, 93 deceased within 28 days of ICU admission. AKI stage 3, critical disease, greater Age and the lowest ratio of partial pressure of oxygen to the fraction of inspired oxygen being < 150 mmHg were independently associated with death.

CONCLUSIONS

Among patients with Covid-19, the incidence of AKI was high. Our findings of the risk factors of the development of AKI and factors associated with renal function recovery may inform clinical management of patients with critical illness of Covid-19.

The predisposing factors of AKI for prophylactic strategies in burn care

Background

Acute kidney injury (AKI) is one of the most severe complications of burn injury. AKI with severe burn injury causes high mortality. This study aims to investigate the incidence of and predisposing factors for AKI in burn patients.

Methods

This is a single-center, retrospective, descriptive criterion standard study conducted from June 27, 2015, to March 8, 2016. We used Kidney Disease Improving Global Outcomes criteria to define and select patients with AKI. The study was conducted by recruiting in hospital patients who suffered from the flammable cornstarch-based powder explosion and were treated under primary care procedures. A total of 49 patients who suffered from flammable dust explosion-related burn injury were enrolled and admitted on June 27, 2015. The patients with more than 20% total body surface area of burn were transferred to the intensive care unit. Patients received fluid resuscitation in the first 24 hours based on the Parkland formula. The primary measurements were the incidence of and predisposing factors for AKI in these patients. Demographic characteristics, laboratory data, and inpatient outcomes were also evaluated. The incidence of AKI in this cohort was 61.2% (n = 30). The mortality rate was 2.0% (n = 1) during a 59-day follow-up period. The multivariate analysis revealed inhalation injury (adjusted OR = 22.0; 95% CI [1.4–358.2]) and meeting ≥3 American Burn Association (ABA) sepsis criteria (adjusted OR = 13.7; 95% CI [1.7–110.5]) as independent risk factors for early advanced AKI.

Conclusions

The incidence rate of AKI was higher in this cohort than in previous studies, possibly due to the flammable dust explosion-related burn injury. However, the mortality was lower than that expected. In clinical practice, indicators of inflammation, including ABA sepsis criteria may help in predicting the risk of AKI in patients with burn injury.

Changing the terminology from kidney replacement therapy to kidney support therapy

Kidney replacement therapy (KRT) is a common supportive treatment for renal dysfunction, especially acute kidney injury. However, critically ill or immunosuppressed patients with renal dysfunction often have dysfunction in other organs as well. To improve patient outcomes, clinicians began to initiate kidney replacement therapy in situations where nonrenal conditions may lead to acute kidney injury, such as septic shock, hematopoietic stem cell transplantation, veno-occlusive renal disease, cardiopulmonary bypass, chemotherapy, tumor lysis syndrome, hyperammonemia, and various others. In this review, we discuss the use of various modes of kidney replacement therapy in treating renal and nonrenal complications to illustrate why kidney support therapy is a more appropriate terminology than kidney replacement therapy.

Acute Kidney Injury After Burn: A Cohort Study From the Parkland Burn Intensive Care Unit

Acute kidney injury (AKI) is a common and morbid complication in patients with severe burn. The reported incidence of AKI and mortality in this population varies widely due to inconsistent and changing definitions. They aimed to examine the incidence, severity, and hospital mortality of patients with AKI after burn using consensus criteria. This is a retrospective cohort study of adults with thermal injury admitted to the Parkland burn intensive care unit (ICU) from 2008 to 2015. One thousand forty adult patients with burn were admitted to the burn ICU. AKI was defined by KDIGO serum creatinine criteria. Primary outcome includes hospital death and secondary outcome includes length of mechanical ventilation, ICU, and hospital stay. All available serum creatinine measurements were used to determine the occurrence of AKI during the hospitalization. All relevant clinical data were collected. The median total body surface area (TBSA) of burn was 16% (IQR: 6%-29%). AKI occurred in 601 patients (58%; AKI stage 1, 60%; stage 2, 19.8%; stage 3, 10.5%; and stage 3 requiring renal replacement therapy [3-RRT], 9.7%). Patients with AKI had larger TBSA burn (median 20.5% vs 11.0%; P < .001) and more mechanical ventilation and hospitalization days than patients without AKI. The hospital death rate was higher in those with AKI vs those without AKI (19.7% vs 3.9%; P < .001) and increased by each AKI severity stage (P trend < .001). AKI severity was independently associated with hospital mortality in the small burn group (for TBSA ≤ 10%: stage 1 adjusted OR 9.3; 95% CI, 2.6-33.0; stage 2-3 OR, 35.0; 95% CI, 9.0-136.8; stage 3-RRT OR, 30.7; 95% CI, 4.2-226.4) and medium burn group (TBSA 10%-40%: stage 2-3 OR, 6.5; 95% CI, 1.9-22.1; stage 3-RRT OR, 35.1; 95% CI, 8.2-150.3). AKI was not independently associated with hospital death in the large burn group (TBSA > 40%). Urine output data were unavailable. AKI occurs frequently in patients after burn. Presence of and increasing severity of AKI are associated with increased hospital mortality. AKI appears to be independently and strongly associated with mortality in patients with TBSA ≤ 40%. Further investigation to develop risk-stratification tools tailoring this susceptible population is direly needed.

Safety, Pharmacodynamics, and Efficacy of High- Versus Low-Dose Ascorbic Acid in Severely Burned Adults

In sepsis and burns, ascorbic acid (AA) is hypothesized advantageous during volume resuscitation. There is uncertainty regarding its safety and dosing. This study evaluated high dose AA (HDAA: 66 mg/kg/h for 24 hours) versus low dose AA (LDAA: 3.5 g/days) administration during the first 24 hours in severely burned adults. We conducted a retrospective study comparing fluid administration before and after switching from low dose to HDAA in severely burned adults. A total of 38 adults with burns >20% TBSA, who received either HDAA or LDAA were included in this retrospective study. AA serum concentrations were quantified at 0, 24, and 72 hours postburn. HDAA impact on hemodynamics, acid-base homeostasis, acute kidney injury, vasopressor use, resuscitation fluid requirement, urinary output, and the incidence of adverse effects was evaluated; secondary clinical outcomes were analyzed. AA plasma levels were 10-fold elevated in the LDAA and 150-fold elevated in the HDAA group at 24 hours and decreased in both groups afterwards. HDAA was not associated with a significantly increased risk of any complications. A significant reduction in colloid fluid requirements was noted (LDAA: 947 ± 1722 ml/24 hours vs HDAA: 278 ± 667 ml/24 hours, P = 0.029). Other hemodynamic and resuscitation measures, as well as secondary clinical outcomes were comparable between groups. HDAA was associated with higher AA levels and lower volumes of colloids in adults with severe burns. The rate of adverse events was not significantly higher in patients treated with HDAA. Future studies should consider prolonged administration of AA.

PenKid measurement at admission is associated with outcome in severely ill burn patients

BACKGROUND

Proenkephalin A 119-159 (penKid) has been proposed as a sensitive biomarker of renal function. This study evaluated the association of concentrations of plasma penKid with death and risk of acute kidney injury (AKI) in severely ill burn patients.

METHODS

A prospective observational study in two centers with severely ill adult burn patients was conducted. The inclusion criteria were total body surface area (TBSA) burns >15%, with burn injury occurring <72 h before intensive care unit (ICU) admission and plasma sample taken at admission. The primary endpoint was 90-day mortality. The secondary endpoints were AKI and a combined endpoint of 90-day mortality and/or AKI. Mortality was also evaluated in the sub-group of patients with sub-clinical AKI, defined as a patient without AKI but with elevated penKid.

RESULTS

A total of 113 consecutive patients were enrolled. The median age was 48 years (Interquartile range [IQR] 33-64), the median burn TBSA was 35% (IQR 25-53), and 90-day mortality was 31.9%. Thirty-one percent of the patients had AKI, and 41.6% of patients had the combined endpoint. There was a stepwise decrease in survival from patients without AKI, sub-AKI, and with AKI (survival rate 90.0% [95% CI 82.7-97.9], 66.7% [95% CI 48.1-92.4], and 31.4% [95% CI 19.3-51.3], respectively, p < 0.001). Plasma penKid concentration was significantly higher in non-survivors compared to survivors (86.9 pmol/L [IQR 53.3-166.1] versus 52.9 pmol/L [IQR 37.1-70.7]; p = 0.0001) and in patients with AKI compared to patients without AKI (86.4 pmol/L [IQR 56.5-153.4] versus 52.5 pmol/L [IQR 35.5-71.2]; p < 0.001). Penkid provided added value on top of serum creatinine (Screat) and Sepsis Related Organ Failure Assessment (SOFA) scores to predict 90-day mortality (combined c-index of 0.738 versus 0.707; p = 0.024 and 0.787 versus 0.752; p < 0.001).

CONCLUSIONS

Plasma penKid concentration at admission was associated with an increased risk of death in burn patients. PenKid has additional prognostic value on top of Screat and SOFA to predict 90-day mortality.

Early Recognition of Burn- and Trauma-Related Acute Kidney Injury: A Pilot Comparison of Machine Learning Techniques

Severely burned and non-burned trauma patients are at risk for acute kidney injury (AKI). The study objective was to assess the theoretical performance of artificial intelligence (AI)/machine learning (ML) algorithms to augment AKI recognition using the novel biomarker, neutrophil gelatinase associated lipocalin (NGAL), combined with contemporary biomarkers such as N-terminal pro B-type natriuretic peptide (NT-proBNP), urine output (UOP), and plasma creatinine. Machine learning approaches including logistic regression (LR), k-nearest neighbor (k-NN), support vector machine (SVM), random forest (RF), and deep neural networks (DNN) were used in this study. The AI/ML algorithm helped predict AKI 61.8 (32.5) hours faster than the Kidney Disease and Improving Global Disease Outcomes (KDIGO) criteria for burn and non-burned trauma patients. NGAL was analytically superior to traditional AKI biomarkers such as creatinine and UOP. With ML, the AKI predictive capability of NGAL was further enhanced when combined with NT-proBNP or creatinine. The use of AI/ML could be employed with NGAL to accelerate detection of AKI in at-risk burn and non-burned trauma patients.

Acute kidney injury in burn patients admitted to the intensive care unit: a systematic review and meta-analysis

Background

Acute kidney injury (AKI) is a common complication in burn patients admitted to the intensive care unit (ICU) associated with increased morbidity and mortality. Our primary aim was to review incidence, risk factors, and outcomes of AKI in burn patients admitted to the ICU. Secondary aims were to review the use of renal replacement therapy (RRT) and impact on health care costs.

Methods

We conducted a systematic search in PubMed, UpToDate, and NICE through 3 December 2018. All reviews in Cochrane Database of Systematic Reviews except protocols were added to the PubMed search. We searched for studies on AKI according to Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease (RIFLE); Acute Kidney Injury Network (AKIN); and/or Kidney Disease: Improving Global Outcomes (KDIGO) criteria in burn patients admitted to the ICU. We collected data on AKI incidence, risk factors, use of RRT, renal recovery, length of stay (LOS), mortality, and health care costs.

Results

We included 33 observational studies comprising 8200 patients. Overall study quality, scored according to the Newcastle-Ottawa scale, was moderate. Random effect model meta-analysis revealed that the incidence of AKI among burn patients in the ICU was 38 (30–46) %. Patients with AKI were almost evenly distributed in the mild, moderate, and severe AKI subgroups. RRT was used in 12 (8–16) % of all patients. Risk factors for AKI were high age, chronic hypertension, diabetes mellitus, high Total Body Surface Area percent burnt, high Abbreviated Burn Severity Index score, inhalation injury, rhabdomyolysis, surgery, high Acute Physiology and Chronic Health Evaluation II score, high Sequential Organ Failure Assessment score, sepsis, and mechanical ventilation. AKI patients had 8.6 (4.0–13.2) days longer ICU LOS and higher mortality than non-AKI patients, OR 11.3 (7.3–17.4). Few studies reported renal recovery, and no study reported health care costs.

Conclusions

AKI occurred in 38% of burn patients admitted to the ICU, and 12% of all patients received RRT. Presence of AKI was associated with increased LOS and mortality.

Trial registration

PROSPERO (CRD42017060420)

Coupled-plasma filtration and adsorption for severe burn patients with septic shock and acute kidney injury treated with renal replacement therapy

BACKGROUND

Coupled-plasma filtration adsorption (CPFA) is a sorbent-based technology aimed at removing soluble mediators of septic shock. We present our experience on the use of CPFA in septic shock severe burn patients with acute kidney injury (AKI) needing renal replacement therapy (RRT) with the main goal to evaluate efficacy and safety of CPFA in this specific subset of septic shock patients.

METHODS

In this observational study, we retrospectively reviewed the medical notes of all burn patients admitted to our adult Burn Center who received CPFA, as part of the septic shock treatment requiring RRT, between January 2001 and December 2017 (CPFA group). We compared CPFA group with all the burn patients admitted to our Center in the same period of time, with the same range of relevant clinical characteristics, who developed AKI and were treated with RRT, but not CPFA (control group). We collected demographic characteristics, burn size, Sequential Organ Assessment Failure (SOFA) score, microbiological data, and patient outcome, in terms of in-hospital mortality rate and the probability of survival calculated using the revised Baux score. We also collected data regarding CPFA safety (hemorrhagic episodes, catheter associated-complications, hypersensitivity reactions) and efficiency (number and duration of CPFA sessions, plasma treated amount, plasma processed dose).

RESULTS

39 severe burn patients were treated with CPFA (CPFA group) (mean age 46.0 years, range 40.0-56.0 years; mean burn size 48.0% TBSA, range 35.0-60.0% TBSA), and 87 patients treated with RRT, but not CPFA, who had similar clinical characteristics (control group). Observed mortality rate was 51.3% in the CPFA group and 77.1% in the control group (p 0.004). Regarding factors affecting survival in the CPFA group, SOFA score on the 1st day of CPFA resulted significant (OR 2.016, 95% CI, 1.221-3.326; p < 0.004) in the multivariate analysis logistic model.

CONCLUSIONS

CPFA treatment for burn patients with AKI-RRT and septic shock, sustained by bacterial strains non or poorly responsive to therapy, was associated with a lower mortality rate, compared to RRT alone. However, further research, such as large prospective studies, is required to clarify the role of CPFA in the treatment of burns with septic shock and AKI-RRT.

Contributing factors and outcomes of burn-associated cholestasis

BACKGROUND & AIMS

Cholestasis often occurs after burn injuries. However, the prevalence of cholestasis and its effect on outcomes in patients with severe burn injuries are unknown. The aim of this study was to describe the course and the burden of cholestasis in a cohort of severely burned adult patients.

METHODS

We investigated the relationship between burn-associated cholestasis (BAC) and clinical outcomes in a retrospective cohort of patients admitted to our unit for severe burn injuries between 2012 and 2015. BAC was defined as an increased level of serum alkaline phosphatase (ALP) ≥1.5x the upper limit of normal (ULN) with an increased level of gamma-glutamyltransferase (GGT) ≥3x ULN, or as an increased level of total bilirubin ≥2x ULN.

RESULTS

A total of 214 patients were included: 111 (52%) patients developed BAC after a median (IQR) stay of 9 (5-16) days. At 90 days, the mortality rate was 20%, including 34 and 9 patients with and without BAC (p <0.001), respectively, which corresponded to a 2.5-fold higher (95% CI 1.2-5.2, p = 0.012) risk of 90-day mortality for patients with BAC. After being adjusted for severity of illness, patients with BAC, hyperbilirubinemia and without elevated ALP and GGT levels had a hazard ratio of 4.51 (95% CI 1.87-10.87) for 90-day mortality. BAC was associated with the severity of the burn injury, shock and bacteraemia. BAC was present in 38 (51%) patients at discharge, and 7 (18%) patients had secondary sclerosing cholangitis. These patients maintained elevated levels of ALP and GGT that were 5.8x (1.7-15) the ULN and 11x the ULN (4.5-22), respectively, 20 months (3.5-35) after discharge.

CONCLUSION

BAC is prevalent among patients with severe burn injuries and is associated with worse short-term outcomes, especially when total bilirubin levels were increased without elevated ALP and GGT levels. BAC survivors are at risk of developing sclerosing cholangitis.

LAY SUMMARY

Cholestasis is common after burn injuries and is associated with burn severity, sepsis, organ failure and mortality. Patients with hyperbilirubinemia without elevated alkaline phosphatase and gamma-glutamyltransferase levels after the burn injury have a poor prognosis. Patients with burn-associated cholestasis may develop sclerosing cholangitis and secondary biliary cirrhosis.

Renal outcomes of intensive care burn patients in an Asian tertiary centre

INTRODUCTION

Acute kidney injury (AKI) is a frequent complication of severe burn injury and is associated with a high mortality rate of up to 80%. We aimed to establish the incidence, mortality rate, and factors related to mortality in adult patients with severe burn injury and AKI with renal replacement therapy (RRT) in Singapore.

METHODS

We performed a retrospective cohort study of severely burned patients who were admitted to the Burns Intensive Care Unit (BICU) at the Singapore General Hospital (SGH) from January 2008 to December 2016. We compared patients with AKI with RRT who survived with those who did not survive. As there were changes in the protocol for burns management after 2013, we also compared patients with AKI with RRT who survived with non-survivors in each of the 2008-2012 and 2013-2016 cohorts.

RESULTS

Data of 201 patients were studied. The incidence of AKI with RRT use in severe burn injury was 21.9% and their mortality rate was 50.0%. The non-survivors had significantly higher median burned total body surface area (p = 0.043), earlier AKI (p = 0.046), earlier use of RRT (p = 0.035), lower rate of renal recovery (p = <0.0001), higher rates of adult respiratory distress syndrome (ARDS) (p = 0.005) and shock with vasopressors (p = 0.009) compared to the survivors. The survival rate was 36.8% in the 2008-2012 cohort, but improved to 60.0% in the 2013-2016 cohort. In the 2008-2012 cohort, the non-survivors developed AKI earlier (day 0 admission vs. day 3 admission, p = 0.039), and were initiated on RRT at lower serum creatinine level (173.5 μmol/L vs. 254.0 μmol/L, p = 0.042), when compared to the survivors in this same cohort. On the other hand, there were no significant differences in the renal status and fluid balance parameters between the non-survivors and survivors in the 2013-2016 cohort.

CONCLUSIONS

The incidence of AKI with RRT in the Singapore study cohort was high, but their mortality rate was relatively lower compared to other study cohorts. Severity of AKI and use of RRT were associated with poor prognosis. Large scale study is required to further study the risk factors for mortality in this group of patients and establish cause-and-effect relationship.

The Interplay of Nutrition, Physical Activity, Severity of Illness, and Mortality in Critically Ill Burn Patients: Is There a Connection?

The purpose of this project was to evaluate the relationships between nutrition, physical activity levels (PALs), severity of illness (SOI), and survival in critically ill burn patients. We conducted a retrospective evaluation of consecutively admitted adult patients who had an intensive care unit stay ≥8 days after ≥20% TBSA burns. Linear regression was used to assess the association between SOI (sequential organ failure assessment scores) and PALs as well as between SOI and nutritional intake. After univariate analysis comparing survivors and nonsurvivors, factors with P < .10 were analyzed with multiple logistic regression. Characteristics of the 45 included patients were: 42 ± 15 years old, 37 ± 17% TBSA burns, 22% mortality. Factors independently associated with survival were burn size (negatively) (P = .018), height (positively) (P = .006), highest PAL during the first eight intensive care unit days (positively) (P = .016), and kcal balance during the fifth through the eighth intensive care unit days (positively) (P = .012). Sequential organ failure assessment scores had a significant (P < .001) but weak association with nutrition intake (R2 = 0.05) and PALs (R2 = 0.25). Higher nutritional intake and activity were significantly associated with lower mortality in critically ill burn patients. Given the weak associations between both nutritional intake and PALs with SOI, the primary barrier in achieving nutrition and activity goals was not SOI. We recommend that physical rehabilitation and nutritional intake be optimized in an effort to improve outcomes in critically ill burn patients.

Relationship Between Burn Wound Location and Outcomes in Severely Burned Patients: More Than Meets the Size

We hypothesized that burn location plays an important role in wound healing, mortality, and other outcomes and conducted the following study to test this multifold hypothesis. We conducted a study to retrospectively look at patients with burns ≥10% TBSA. Demographics, TBSA, partial/full thickness burns (PT/FT) in various wound locations, fluids, inhalation injury, mortality, ICU duration, and hospital duration were considered. Initial wound healing rates (%/d) were also calculated as a slope from the time of the first mapping of open wound size to the time of the third mapping of open wound size. Multivariate logistic regression and operating curves were used to measure mortality prediction performance. All values were expressed as median [interquartile range]. The mortality rate for 318 patients was 17% (54/318). In general, patients were 43 years [29, 58 years] old and had a TBSA of 25% [17, 39%], PT of 16% [10, 25%], and FT of 4% [0, 15%]. Between patients who lived and did not, age, TBSA, FT, 24-hour fluid, and ICU duration were statistically different (P < .001). Furthermore, there were statistically significant differences in FT head (0% [0, 0%] vs 0% [0, 1%], P = .048); FT anterior torso (0% [0, 1%] vs 1% [0, 4%], P < .001); FT posterior torso (0% [0, 0%] vs 0% [0, 4%], P < 0.001); FT upper extremities (0% [0, 3%] vs 2% [0, 11%], P < .001); FT lower extremities (0% [0, 2%] vs 6% [0, 17%], P < .001); and FT genitalia (0% [0, 0%] vs 0% [0, 2%], P < .001). Age, presence of inhalation injury, PT/FT upper extremities, and FT lower extremities were independent mortality predictors and per unit increases of these variables were associated with an increased risk for mortality (P < .05): odds ratio of 1.09 (95% confidence interval [CI] = 1.61–1.13; P < .001) for mean age; 2.69 (95% CI = 1.04–6.93; P = .041) for inhalation injury; 1.14 (95% CI = 1.01–1.27; P = .031) for mean PT upper extremities; 1.26 (95% CI = 1.11–1.42; P < .001) for mean FT upper extremities; and 1.07 (95% CI = 1.01–1.12; P = .012) for mean FT lower extremities. Prediction of mortality was better using specific wound locations (area under the curve [AUC], AUC of 0.896) rather than using TBSA and FT (AUC of 0.873). Graphs revealed that initial healing rates were statistically lower and 24-hour fluids and ICU length of stay were statistically higher in patients with FT upper extremities than in patients without FT extremities (P < .001). Burn wound location affects wound healing and helps predict mortality and ICU length of stay and should be incorporated into burn triage strategies to enhance resource allocation or stratify wound care.

Artificial intelligence and machine learning for predicting acute kidney injury in severely burned patients: A proof of concept

BACKGROUND

Burn critical care represents a high impact population that may benefit from artificial intelligence and machine learning (ML). Acute kidney injury (AKI) recognition in burn patients could be enhanced by ML. The goal of this study was to determine the theoretical performance of ML in augmenting AKI recognition.

METHODS

We developed ML models using the k-nearest neighbor (k-NN) algorithm. The ML models were trained-tested with clinical laboratory data for 50 adult burn patients that had neutrophil gelatinase associated lipocalin (NGAL), urine output (UOP), creatinine, and N-terminal B-type natriuretic peptide (NT-proBNP) measured within the first 24 h of admission.

RESULTS

Half of patients (50%) in the dataset experienced AKI within the first week following admission. ML models containing NGAL, creatinine, UOP, and NT-proBNP achieved 90-100% accuracy for identifying AKI. ML models containing only NT-proBNP and creatinine achieved 80-90% accuracy. Mean time-to-AKI recognition using UOP and/or creatinine alone was achieved within 42.7 ± 23.2 h post-admission vs. within 18.8 ± 8.1 h via the ML-algorithm.

CONCLUSIONS

The performance of UOP and creatinine for predicting AKI could be enhanced by with a ML algorithm using a k-NN approach when NGAL is not available. Additional studies are needed to verify performance of ML for burn-related AKI.

Protective effect of anisodamine in rats with glycerol-induced acute kidney injury

Background

Anisodamine is used for the treatment of reperfusion injury in various organs. In this study, we investigated the effectiveness and mechanisms of action of anisodamine in promoting recovery from glycerol-induced acute kidney injury (AKI).

Methods

We compared the protective effects of atropine and anisodamine in the rat model of glycerol-induced AKI. We examined signaling pathways involved in oxidative stress, inflammation and apoptosis, as well as expression of kidney injury molecule-1 (KIM-1). Renal injury was assessed by measuring serum creatinine and urea, and by histologic analysis. Rhabdomyolysis was evaluated by measuring creatine kinase levels, and oxidative stress was assessed by measuring malondialdehyde (MDA) and superoxide dismutase (SOD) levels in kidney tissues. Inflammation was assessed by quantifying interleukin 6 (IL-6) and CD45 expression. Apoptosis and necrosis were evaluated by measuring caspase-3 (including cleaved caspase 3) and RIP3 levels, respectively.

Results

Glycerol administration resulted in a higher mean histologic damage score, as well as increases in serum creatinine, urea, creatine kinase, reactive oxygen species (ROS), MDA, IL-6, caspase-3 and KIM-1 levels. Furthermore, glycerol reduced kidney tissue SOD activity. All of these markers were significantly improved by anisodamine and atropine. However, the mean histologic damage score and levels of urea, serum creatinine, creatine kinase, ROS and IL-6 were lower in the anisodamine treatment group compared with the atropine treatment group.

Conclusion

Pretreatment with anisodamine ameliorates renal dysfunction in the rat model of glycerol-induced rhabdomyolytic kidney injury by reducing oxidative stress, the inflammatory response and cell death.

Improved outcomes of renal injury following burn trauma

BACKGROUND

Acute kidney injury (AKI) is common in major burn injuries and associated with increased mortality. With advances in surgical and critical care it is unclear if mortality in this population remains this high. This study aims to describe incidence and outcomes of patients admitted to intensive care (ICU) with a burn injury who develop AKI. We additionally sought to determine risk factors for developing AKI.

METHODS

A historical cohort study of patients admitted to ICU from 2010 to 2016 with major burn injury was conducted. Demographic, laboratory, and clinical information was collected. AKI was defined by Acute Kidney Injury Network (AKIN) classification. Multivariable logistic regression was used to model association between baseline risk factors and risk of AKI.

RESULTS

Of the 151 patients included, 64 people developed AKI (42%) defined by stages 1-3 of AKIN criteria. The median TBSA was 20% (IQR 9-41). Renal replacement therapy was required in 18/64 (28%) who developed AKI. Multivariable logistic regression demonstrated association between AKI and the following variables: APACHE II score (OR 1.2, 95%CI 1.1-1.3, P = 0.001), age (OR 1.8 per 10-year increase, 95%CI: 1.2-2.5, P = 0.002) and log(TBSA). Fractional polynomial regression analysis demonstrates that the best functional form of TBSA was in the natural logarithm (OR 2.7, 95%CI: 1.5-4.7, p = 0.001). Compared to those without AKI, patients with AKI had longer duration of mechanical ventilation, (median 11 [IQR 6-19] vs. 4 [IQR 2-9] days), ICU stay (15 [IQR 9-22] vs. 6 [IQR 3-10] days), and increased mortality (14 of 64(22%) vs. 4 of 87(5%).

CONCLUSIONS

AKI is common in patients with a major burn injury. However, mortality is lower than described in the literature, particularly for those who required renal replacement therapy.

Predictive Biomarkers for Acute Kidney Injury in Burn Patients

Acute kidney injury (AKI) is an independent and complicated risk factor in burn patients, which cause high mortality and morbidity rate. Diagnosing the biomarkers and early detection of AKI may be helpful in treatment and control the stability of these patients. In this study, we aim to identify predictive biomarkers in order to prevent AKI incidence and sudden death in burn victims. In this retrospective study, 258 burn patients who were admitted to burn center in Shiraz, Iran were evaluated during January 2016 to February 2018. Demographic characteristics, biochemical biomarkers, length of hospital stay, and mortality information were obtained from patient registries program and evaluated the biomarkers in identifying AKI patients into early and late groups. Receiver operating characteristic curve, area under the curve (AUC), univariate, and multivariate logistic regression analysis were used to diagnose the performance of biomarkers in order to predict the AKI. Of 258 patients, 40 (15.50%) were detected as AKI, with estimated mortality rate of 76.9%. Among all the variables, total BSA (P = .01), blood urea nitrogen (BUN; P = .001), potassium (P = .02), and mortality (P = .03) were significantly different in AKI developing. Moreover, AUC of serum creatinin, albumin, and BUN as predictive biomarkers were 0.73, 0.44, and 0.707, respectively. Among all variables, BUN marker was independently associated with AKI developing. Following burn shock, AKI is a common complication that causes increasing mortality and morbidity. Early diagnosis and identifying the biomarkers is preventing sudden death in burn patients and develop appropriate treatments in these victims.

Acute kidney injury after burn surgery: Preoperative neutrophil/lymphocyte ratio as a predictive factor

BACKGROUND

Severe inflammation and acute kidney injury (AKI) are serious adverse events after burn injuries. The neutrophil/lymphocyte ratio (NLR) is a marker of inflammation. We evaluated the independent risk factors for postoperative AKI, including NLR, in burn-injured patients.

METHODS

The preoperative, intraoperative, and postoperative variables of 473 burn-injured patients were collected. The risk factors for AKI after burn surgery were evaluated using univariate and multivariate logistic regression analyses. The receiver operating characteristic (ROC) curve analysis of preoperative NLR was performed. The 3-month mortality after surgery was also compared between AKI and non-AKI groups using Kaplan-Meier analysis with a log-rank test.

RESULTS

Postoperative AKI occurred in 71 of 473 (15.0%) burn patients. The total body surface area burned (odds ratio (OR), 1.013; 95% confidence interval (CI), 1.001-1.026; P = 0.037), inhalation injury (OR, 1.821; 95% CI, 1.008-3.292; P = 0.047), and preoperative NLR (OR, 1.094; 95% CI, 1.064-1.125; P < 0.001) were risk factors for AKI after surgery. The area under the ROC curve was 0.767, with an optimal cut-off value of 11.7. Moreover, the 3-month mortality after surgery was significantly higher in the AKI group than in the non-AKI group (49.3% vs 14.9%, P < 0.001).

CONCLUSION

Total body surface area burned, inhalation injury, and preoperative NLR are risk factors for AKI after burn surgery, which is associated with early postoperative mortality. Preoperative NLR can provide useful information for the early detection of postoperative AKI and subsequent mortality in burn-injured patients.

Factors associated with acute kidney injury in the Helsinki Burn Centre in 2006-2015

BACKGROUND

Acute kidney injury (AKI) is a common complication in severe burns and can lead to significantly poorer outcomes. Although the prognosis has improved in recent decades, the mortality of AKI remains considerable. We investigated the factors that increase the risk of AKI and death after severe burn injury.

METHODS

Intensive care patients with ≥20% burned total body surface area (TBSA%) between January 2006 and December 2015 treated in Helsinki Burn Centre were enrolled retrospectively. Patients who arrived > 36 h after burn injury or died < 48 h from arrival were excluded. A total of 187 patients were included in the final analysis. Serum creatinine ≥120 μmol/l (1.4 mg/dl) was the criterion for AKI.

RESULTS

Fifty-one patients (27.3%) developed AKI during hospital stay and 21 (11.2%) required renal replacement therapy (RRT); 37 patients (19.8%) died during hospital stay. Mortality was significantly higher in the AKI group (52.9%) than in the AKI-negative group (7.4%). The Abbreviated Burn Severity Index (ABSI), Baux, and the modified Baux score were nearly equivalent in predicting mortality during ICU stay (AUC: 0.83-0.84). The risk of death and AKI were minimal with Baux scores < 80. LD₅₀ was 112 for Baux score in all patients. In flame burns, the risk of death increased rapidly after Baux score > 80. Multivariate logistic regression model detected age, TBSA%, sepsis, and rhabdomyolysis as independent risk factors for AKI. Age (per 10 yrs. OR 1.99), TBSA% (per 10% OR 1.64), and AKI predicted mortality during hospital stay; AKI had an odds ratio of (OR) of 5.97 (95% confidence interval [CI] 2.2-16.2).

CONCLUSIONS

Age, TBSA%, and AKI were the strongest independent factors in predicting outcome in severe burns. Even a major burn (> 50% TBSA) has a relatively good prognosis without simultaneous AKI. Prognosis is poorer even in minor burns for patients with AKI.

Microfluidic Assay Measures Increased Neutrophil Extracellular Traps Circulating in Blood after Burn Injuries

Cell-free DNA (cf-DNA) concentration in human plasma is often increased after burn and trauma injuries. Two major sources of cf-DNA are the parenchymal cells damaged by the injury and various circulating cells indirectly altered by the response to injury. The cf-DNA originating from neutrophils, also known as circulating neutrophil extracellular traps (cNETs), is of notable interest because cNETs have been associated with pathological processes in other conditions, including cancer, autoimmunity, etc. Both intact chromatin and oligonucleotides, which are the by-product of cf-DNA degradation, are assumed to contribute to the cf-DNA in patients. However, traditional assays for cf-DNA quantification do not distinguish between cNETs and cf-DNA of other origins and do not differentiate between intact chromatin and oligonucleotides. Here we measure the amount of intact cNETs in the circulation, using a microfluidic device that mechanically traps chromatin fibers directly from blood and an immunofluorescence protocol that detects neutrophil-specific proteins associated with chromatin. In a rat model of burn injury, we determined that the chromatin fibers in the circulation after injury originate exclusively from neutrophils and are cNETs. We found that the concentration of cNETs surges the first day after injury and then decreases slowly over several days. In a secondary sepsis model, which involved a burn injury followed by cecal-ligation-puncture, we measured additional increases in cNETs in the days after sepsis was induced. These results validate a microfluidic assay for the quantification of cNETs and will facilitate fruther studies probing the contribution of cNETs to complications after burns and sepsis.

Hypertonic saline resuscitation protects against kidney injury induced by severe burns in rats

BACKGROUND

Proper fluid resuscitation can relieve visceral damage and improve survival in severely burned patients. This study compared the effectiveness of resuscitation with 400mEq/L hypertonic saline (HS) and sodium lactate Ringer's solution (LR) in rats with kidney injury caused by burn trauma.

METHODS

Rats (Sprague-Dawley) underwent burn injury and were randomized into sham, LR, and HS groups. Samples from the kidney were assayed for water content ratio, histopathology, and oxidative stress (superoxide dismutase (SOD) and malondialdehyde (MDA)). Serum sodium, renal function (creatinine and cystatin (Cys)-C), and inflammatory response (tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and high mobility group protein box (HMGB)-1) were also examined as serum markers.

RESULTS

Hypertonic saline resuscitation reduced the renal water content ratio and improved renal histopathology caused by severe burns. This effect was accompanied by reductions in serum creatinine and Cys-C as well as TNF-α, IL-1β, and HMGB1. Serum sodium concentration and SOD activity were increased, whereas MDA content was decreased in the kidney tissue of the HS group.

CONCLUSIONS

The data indicate that 400mEq/L HS solution reduces hyponatremia and renal edema, inhibits the release of inflammatory mediators, and alleviates oxidative stress injury, thus protecting against kidney injury induced by severe burns.

Prediction of major adverse kidney events in critically ill burn patients

OBJECTIVE

We aimed at assessing the predictive value of plasmatic Neutrophil Gelatinase Associated Lipocalin (pNGAL) at admission and severity scores to predict major adverse kidney events (MAKE, defined as death and/or need for renal replacement therapy (RRT) and/or non-renal recovery at day 90) in critically ill burn patients.

MATERIAL AND METHODS

Single-center cohort study in a burn critical care unit in a tertiary center, including all consecutive severely burn patients (total burned body surface >20%) from January 2012 until January 2015 with a pNGAL dosage at admission. Reclassification of patients was assessed by Integrated Discrimination Improvement (IDI).

MEASUREMENTS AND RESULTS

87 patients were included. Mean age was 47.7 (IQ 25-75: 33.4-65.2) years; total burn body surface area was 40 (IQ 25-75: 30-55) % and ICU mortality 36%. 39 (44.8%) patients presented a MAKE, 32 (88.9%) patients died at day 90. pNGAL was higher in the MAKE group (423 [IQ 25-75: 327-518]pg/mL vs 184 [IQ 25-75: 147-220]pg/mL, p<0.001). In multivariate analysis, pNGAL and abbreviated burn severity index (ABSI) remained associated with MAKE (OR 1.005 [CI 95% 1.0005-1.009], p=0.03 and OR 1.682 [CI95%1.038-2.726], p=0.035 respectively). Adding pNGAL to abbreviated burn severity index, simplified organ failure assessment and the simplified acute physiology score 2 did outperform clinical scores for the prediction of MAKE and AKI and for most severe forms of AKI and allowed a statistically significant reclassification of patients compared to ABSI for MAKE, RRT, AKI at Day 7 and AKI during hospitalization with a number of patients needed to screen to detect one extra episode of MAKE was 44, 13 for severe AKI and 15 for AKI.

CONCLUSIONS

pNGAL at admission is associated with the risk of MAKE in this population, and outperform severity scores when associated. Interventional studies are now needed to assess if impact of biomarkers-guided strategies would improve outcome.

Risk Factors for Acute Kidney Injury in Patients With Burn Injury: A Meta-Analysis and Systematic Review

Acute kidney injury (AKI) is a fatal complication of burn injury. Few systematic reviews to date have focused on the risk factors predisposing to AKI in patients with burn injury. The aim of this article is to identify the risk factors for the occurrence of AKI in burn patients, thus providing theoretical evidence for prevention and treatment. We performed a systematic review and meta-analysis of studies determining the prevalence, risk factors, and outcomes of AKI in patients with burn injury. An electronic search (up to April 2016) was performed using Pubmed, Embase, Web of Knowledge, and the Cochrane Library databases. Finally, a total of 18 articles (nine prospective cohort, seven retrospective cohort, two case-control) meeting the eligibility criteria were included. The pooled incidence of AKI was 39.6% (95% confidence interval = 34.7-44.4%). Significant risk factors for the occurrence of AKI included age (odds ratio [OR] = 3.78 [1.28-6.27]), TBSA (OR = 15.66 [11.01-20.31]), full-thickness TBSA (OR = 15.66 [11.01-20.31]), flame burn (OR = 1.56 [1.09-2.25]), inhalation injury (OR = 2.97 [1.80-4.89]), abbreviated burn severity index on admission (OR = 2.42 [1.87-2.98]), sequential organ failure assessment score on admission (OR = 2.69 [1.39-3.98]), baseline blood urea nitrogen (OR = 2.11 [0.72-3.51]), serum creatinine (OR = 2.69 [1.39-3.98]), and sepsis (OR = 4.42 [1.75-11.18]). In addition, burn patients with AKI are more likely to have long stay in intensive care unit and high mortality. AKI is a common complication and occurs at a remarkable rate in burn patients. We identified 10 variables as independent risk factors for the development of AKI in burn patients. Our findings may help clinicians to develop effective preventive and therapeutic strategies and provide appropriate, timely initial treatment.

Enteral resuscitation with oral rehydration solution to reduce acute kidney injury in burn victims: Evidence from a porcine model

Intravenous (IV) resuscitation of burn patients has greatly improved outcomes and become a cornerstone of modern burn care. However, the heavy fluids and vascular access required may not be feasible in austere environments, mass casualty, or delayed transport scenarios. Enteral resuscitation has been proposed for these situations; we sought to examine the effectiveness of this strategy on improving burn-induced kidney injury. Anesthetized Yorkshire swine sustaining 40% TBSA full-thickness contact burns were randomized to three groups (n = 6/group): fluid deprivation, ad libitum water access, or 70 mL/kg/d Oral Rehydration Salt solution (ORS). Urine and blood were collected at baseline (BL), 6, 12, 24, 32, and 48h post-burn, at which point tissue was harvested and CT angiography performed. Although fluid consumption by ad libitum and ORS groups were matched (132±54mL/kg versus 120±24mL/kg, respectively), ORS intake increased urine output compared with water and no water (47.3±9.0 mL/kg versus 16.1±2.5 mL/kg, and 24.5±1.7 mL/kg respectively). Plasma creatinine peaked 6h following burn (1.67±0.07mg/dL) in all animals, but at 48h was comparable to BL in animals receiving water (1.23±0.06mg/dL) and ORS (1.30±0.09mg/dL), but not fluid deprived animals (1.56±0.05mg/dL) (P<0.05). Circulating levels of blood urea nitrogen steadily increased, but also decreased by 48h in animals receiving enteral fluids (P<0.05). Water deprivation reduced renal artery diameter (-1.4±0.17mm), whereas resuscitation with water (-0.44±0.14 mm) or ORS maintained it (-0.63±0.20 mm;P< 0.02). Circulating cytokines IL-1β, IL-6, IFNγ, and GM-CSF were moderately elevated in the fluid-deprived group. Taken together, the data suggest that enteral resuscitation with ORS rescues kidney function following burn injury. Incorporating enteral fluids may improve outcomes in resource-poor environments and possibly reduce IV fluid requirements to prevent co-morbidities associated with over-resuscitation. Studies into different volumes/types of enteral fluids are warranted. While ORS has saved many lives in cholera-associated dehydration, it should be investigated further for use in burn patients.

Determinants of Outcome in Burn ICU Patients with Septic Shock

Infectious complications remain one of the most challenging concerns for the burn team. The goal of this study was to evaluate the diagnostic and therapeutic approaches and prognosis in burn patients with septic shock. This retrospective study included patients with severe burn injury who were admitted to a burn intensive care unit (ICU). Demographic and clinical data were recorded for each patient. The diagnostic and prognostic value of a number of clinical and laboratory parameters and various treatment options were evaluated. Sixty-four of the 378 patients (16.9%) were identified as having experienced a septic shock during ICU stay. The mortality rate of patients with septic shock was 46.9%. The main bacterial strains responsible for infection were Gram-negative bacteria (78.1%). Factors associated with outcome of septic shock on logistic regression analysis were presence of stage III of acute kidney injury (odds ratio [95% confidence interval] 2.03 [1.06-3.84]; P = 0.019), and lactate levels > 4 mmol/L during the first 48 hours of shock (odds ratio 1.92; 95% confidence interval: 1.02-3.62; P = 0.043). Prognosis of septic shock remains poor in burn patients with septic shock. The main causative pathogens of septic shock identified in our burn ICU were Gram-negative species. The main prognostic factors identified in this study were the presence of AKI, stage III, and high lactate levels early after the onset of septic shock.

Extracorporeal Life Support Use in Adult Burn Patients

Burn-related cardiopulmonary failure causes significant morbidity and is associated with increased risk of death. Extracorporeal life support (ECLS) may be used to support burn patients, but its efficacy and safety in this population have not been well defined. This study examined survival rates and risk factors for death in adult burn patients who received ECLS. Retrospective data from the Extracorporeal Life Support Organization international registry were analyzed to determine clinical outcomes and risk factors for death in adult burn patients treated with ECLS. During the study period, we identified 58 adult burn patients who were treated with ECLS. Overall survival to hospital discharge was 43%. Survivors and nonsurvivors were similar in age, gender, body weight, mode of ECLS used, and duration of ECLS. Nonsurvivors had lower pH values (7.15 vs 7.30, P < .001) and higher pCO2 values (65.5 vs 50.5, P = .038) before initiation of ECLS. Nonsurvivors had higher rates of renal failure (49 vs 16%, P = .01) and renal replacement therapy (70 vs 36%, P = .016). Infection was documented in 21 patients; survival in this group was 43%. Multivariate logistic regression analysis identified acidosis (pH < 7.16) and the use of inotropic/vasopressor medications before ECLS as risk factors associated with increased risk of mortality. ECLS appears to be a viable treatment option for adult burn patients with cardiopulmonary failure. ECLS survival in adult burn victims is similar to that observed in nonburn patient populations treated with ECLS.

Acute Kidney Injury: It's not just the 'big' burns

BACKGROUND

Acute Kidney Injury (AKI) complicates the management of at least 25% of patients with severe burns and is associated with long term complications. Most research focuses on the patients with more severe burns, and whether the same factors are associated with the development of AKI in patients with burns between 10 and 19% total body surface area (TBSA) is unknown. The aims of this study were to examine the incidence of, and factors associated with, the development of AKI in patients with %TBSA≥10, as well as the relationship with hospital metrics such as length of stay (LOS).

METHODS

Retrospective medical record review of consecutive burns patients admitted to The Alfred Hospital, the major adult burns centre in Victoria, Australia. Demographic and injury details were recorded. Factors associated with AKI were determined using multiple logistic regression.

RESULTS

Between 2010 and June 2014, 300 patients were admitted with burn injury and data on 267 patients was available for analysis. Median age was 54.5 years with 78% being male. Median %TBSA was 15 (IQR 12, 20). The AKI incidence, as measured by the RIFLE criteria, was 22.5%, including 15% (27/184) in patients with %TBSA 10-19. Factors associated with AKI included increasing age and %TBSA (OR 1.05 p<0.001) as well as increased surgeries (p<0.041) and a cardiac comorbidity (p<0.01). All patients with renal comorbidity developed AKI. In the %TBSA 10-19 cohort, only increasing age (OR 1.05 p<0.001) was associated with AKI. After accounting for confounding factors, the probability of discharge from hospital in Non-AKI group was greater than for the AKI patients at all time points (P<0.001).

CONCLUSION

This is the first study to show an association between patients with %TBSA 10-19 and AKI. Given the association between AKI and complications, prospective research is needed to further understand AKI in burns with the aim of risk reduction.

The effects of major burn related pathophysiological changes on the pharmacokinetics and pharmacodynamics of drug use: An appraisal utilizing antibiotics

Patients suffering major burn injury represent a unique population of critically ill patients. Widespread skin and tissue damage causes release of systemic inflammatory mediators that promote endothelial leak, extravascular fluid shifts, and cardiovascular derangement. This phase is characterized by relative intra-vascular hypovolaemia and poor peripheral perfusion. Large volume intravenous fluid resuscitation is generally required. The patients' clinical course is then typically complicated by ongoing inflammation, protein catabolism, and marked haemodynamic perturbation. At all times, drug distribution, metabolism, and elimination are grossly distorted. For hydrophilic agents, changes in volume of distribution and clearance are marked, resulting in potentially sub-optimal drug exposure. In the case of antibiotics, this may then promote treatment failure, or the development of bacterial drug resistance. As such, empirical dose selection and pharmaceutical development must consider these features, with the application of strategies that attempt to counter the unique pharmacokinetic changes encountered in this setting.

Comparison of acute kidney injury of different etiology reveals in-common mechanisms of tissue damage

Acute kidney injury (AKI) is a syndrome of reduced glomerular filtration rate and urine production caused by a number of different diseases. It is associated with renal tissue damage. This tissue damage can cause tubular atrophy and interstitial fibrosis that leads to nephron loss and progression of chronic kidney disease (CKD). This review describes the in-common mechanisms behind tissue damage in AKI caused by different underlying diseases. Comparing six high-quality microarray studies of renal gene expression after AKI in disease models (gram-negative sepsis, gram-positive sepsis, ischemia-reperfusion, malignant hypertension, rhabdomyolysis, and cisplatin toxicity) identified 5,254 differentially expressed genes in at least one of the AKI models; 66% of genes were found only in one model, showing that there are unique features to AKI depending on the underlying disease. There were in-common features in the form of four genes that were differentially expressed in all six models, 49 in at least five, and 215 were found in common between at least four models. Gene ontology enrichment analysis could be broadly categorized into the injurious processes hypoxia, oxidative stress, and inflammation, as well as the cellular outcomes of cell death and tissue remodeling in the form of epithelial-to-mesenchymal transition. Pathway analysis showed that MYC is a central connection in the network of activated genes in-common to AKI, which suggests that it may be a central regulator of renal gene expression in tissue injury during AKI. The outlining of this molecular network may be useful for understanding progression from AKI to CKD.