Acute kidney injury is common, parallels organ dysfunction or failure, and carries appreciable mortality in patients with major burns: a prospective exploratory cohort study

The impact and validity of the Berlin criteria on burn-induced ARDS: Examining mortality rates, and inhalation injury influences. A single center observational cohort study

BACKGROUND

As several recent studies have shown low mortality rates in burn injury induced ARDS early (≤7 days) after the burn, the Berlin criteria for the ARDS diagnosis in this setting may be disputed. Related to this issue, the present study investigated the incidence, trajectory and risk factors of early Acute Respiratory Distress Syndrome (ARDS) and outcome in burn patients, as per the Berlin criteria, along with the concurrent prevalence and influence of inhalation injury, and ventilator-acquired pneumonia (VAP).

METHODS

Over a 2.5-year period, burn patients with Total Burn Surface Area (TBSA) exceeding 10% admitted to a national burn center were included. The subgroup of interest comprised patients with more than 48 h of ventilatory support. This group was assessed for ARDS, inhalation injury, and VAP.

RESULTS

Out of 292 admissions, 62 sustained burns > 10% TBSA. Of these, 28 (45%) underwent ventilatory support for over 48 h, almost all, 24 out of 28, meeting the criteria for ARDS early, within 7 days post-injury and with a PaO2/FiO2 (PF) ratio nadir at day 5. The mortality rate for this early ARDS group was under 10%, regardless of PF ratios (mean TBSA% 34,8%). Patients with concurrent inhalation injury and early ARDS showed significantly lower PF ratios (p < 0.001), and higher SOFA scores (p = 0.004) but without impact on mortality. Organ failure, indicated by SOFA scores, peaked early (day 3) and declined in the first week, mirroring PF ratio trends (p < 0.001).

CONCLUSIONS

The low mortality associated with early ARDS in burn patients in this study challenges the Berlin criteria's for the early ARDS diagnosis, which for its validity relies on that higher mortality is linked to worsening PF ratios. The finding suggests alternative mechanisms, leading to the early ARDS diagnosis, such as the significant impact of inhalation injury on early PF ratios and organ failure, as seen in this study. The concurrence of early organ failure with declining PF ratios, supports, as expected, the hypothesis of trauma-induced inflammation/multi-organ failure mechanisms contributing to early ARDS. The study highlights the complexity in differentiating between the contributions of inhalation injury to early ARDS and the related organ dysfunction early in the burn care trajectory. The Berlin criteria for the ARDS diagnosis may not be fully applicable in the burn care setting, where the low mortality significantly deviates from that described in the original Berlin ARDS criteria publication but is as expected when considering the actual not very extensive burn injury sizes/Baux scores as in the present study.

CytoSorb® in burn patients with septic shock and Acute Kidney Injury on Continuous Kidney Replacement Therapy is associated with improved clinical outcome and survival

BACKGROUND

In burn patients, septic shock and acute kidney injury (AKI) with use of continuous renal replacement therapy (CRRT) severely increase morbidity and mortality. Sorbent therapies could be an adjunctive therapy to address the underlying metabolic changes in inflammatory and anti-inflammatory cytokines dysregulated production.

METHODS

A retrospectively observational study of 35 severe burn patients admitted to the Burn Center (Turin, Italy, from January 2017 to December 2022), who underwent CRRT for AKI-associated septic shock. Out of 35 patients, 11 were treated with CytoSorb® as adjunctive therapy to CRRT (Sorbent group) and 24 patients only with CRRT (Control group).

RESULTS

The application of CytoSorb® took place in a very dispersed way. Out of 11 patients, 7 started the CRRT together with the sorbent application. The patients of the sorbent group exhibited a significant reduction in norepinephrine use compared to that of the control group. A clinical improvement over the first 4 days of Cytosorb® was observed in both survivors and no survivors of the sorbent group, with significant norepinephrine decreased use on day 4 compared to day 1. In-hospital mortality was 45.4% and 70.8% in the sorbent and control group, respectively, and significantly better at Kaplan-Meier survival analysis at 270 days (p = 0.0445). In both groups, all survivor patients recovered renal function at discharge, whereas no survivors did not.

CONCLUSIONS

Adjunctive treatment with CytoSorb® for burn patients with AKI-CRRT and septic shock poorly responsive to standard therapy led to a significant clinical improvement, and was associated with a lower mortality rate compared to CRRT alone.

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.

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.

VARIABLES INFLUENCING THE DIFFERENTIAL HOST RESPONSE TO BURNS IN PEDIATRIC AND ADULT PATIENTS

ABSTRACT

Burn injury is a significant source of morbidity and mortality in the pediatric population. Although 40,000 pediatric patients in the United States are admitted to the hospital with burn wounds annually, significant differences exist in the management and treatment of these patients, even among highly specialized burn centers. Some aspects of pediatric burn research, such as metabolic changes and nutritional support after burn injury, have been studied extensively; however, in many aspects of burn care, pediatric research lags behind the study of adult populations. This review compares and contrasts a wide array of physiologic and immune responses between children and adults after burn injury. Such a review elucidates where robust research has been conducted, where adult research is applicable to pediatric patients, and where additional pediatric burn research needs to be conducted.

In Situ Identification of Unknown Crystals in Acute Kidney Injury Using Raman Spectroscopy

Raman spectroscopy is a well-established and powerful tool for in situ biomolecular evaluation. Type 2 crystal nephropathies are characterized by the deposition of crystalline materials in the tubular lumen, resulting in rapid onset of acute kidney injury without specific symptoms. Timely crystal identification is essential for its diagnosis, mechanism exploration and therapy, but remains challenging. This study aims to develop a Raman spectroscopy-based method to assist pathological diagnosis of type 2 crystal nephropathies. Unknown crystals in renal tissue slides from a victim suffered extensive burn injury were detected by Raman spectroscopy, and the inclusion of crystals was determined by comparing Raman data with established database. Multiple crystals were scanned to verify the reproducibility of crystal in situ. Raman data of 20 random crystals were obtained, and the distribution and uniformity of substances in crystals were investigated by Raman imaging. A mouse model was established to mimic the crystal nephropathy to verify the availability of Raman spectroscopy in frozen biopsy. All crystals on the human slides were identified to be calcium oxalate dihydrate, and the distribution and content of calcium oxalate dihydrate on a single crystal were uneven. Raman spectroscopy was further validated to be available in identification of calcium oxalate dihydrate crystals in the biopsy specimens. Here, a Raman spectroscopy-based method for in situ identification of unknown crystals in both paraffin-embedded tissues and biopsy specimens was established, providing an effective and promising method to analyze unknown crystals in tissues and assist the precise pathological diagnosis in both clinical and forensic medicine.

ABO blood group and effects on ventilatory time, length of stay and mortality in major burns a retrospective observational outcome study

Blood group has been found to be important in the development of many diseases and the outcome of several disease processes, especially cardiovascular morbidity and mortality, such as caused by trauma and sepsis. The main reason is claimed to be related to glycobiology and effects mediated through the endothelium. This study investigated the possible effect of blood group (ABO) on burn care outcome. Burn outcome prediction models are extremely accurate and as such can be used to identify outcome effects even in single centre settings. In this retrospective risk adjusted observational study, we investigated the effect of ABO blood group on ventilatory time, length of hospital stay (LOS), and 90 day mortality among patients with burns. RESULTS: A total of 225 patients were included (2008-2019) with median TBSA of 26%; interquartile range (IQR) of 20-37%; median age 45 years (IQR 22-65 years); median Baux score (age + TBSA%); 76 (IQR 53- 97); 168 (75%) were male; median duration of hospital stay was 31 days (IQR 19-56); a total of 138 (61%) received treatment with mechanical ventilation; and 29 (13%) died. In a multivariable regression model, we were unable to isolate any significant effect of any blood group (O, A, B, AB) on the outcome measures studied (ventilatory time, LOS, and mortality). IN SUMMARY: contrary to many other major areas of disease in which ABO blood groups affect outcome, we were unable to find any such effect on patients with burns. Given the precision of the outcome models presented (AUC 0.93) any such an effect, if missed due to the limited study cohort, may be considered limited and to have only a minor clinical impact.

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 &gt;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 &lt; 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.

Addition of admission lactate levels to Baux score improves mortality prediction in severe burns

Risk adjustment and mortality prediction models are central in optimising care and for benchmarking purposes. In the burn setting, the Baux score and its derivatives have been the mainstay for predictions of mortality from burns. Other well-known measures to predict mortality stem from the ICU setting, where, for example, the Simplified Acute Physiology Score (SAPS 3) models have been found to be instrumental. Other attempts to further improve the prediction of outcome have been based on the following variables at admission: Sequential Organ Failure Assessment (_aSOFA) score, determinations of _aLactate or Neutrophil to Lymphocyte Ratio (_aNLR). The aim of the present study was to examine if estimated mortality rate (EMR, SAPS 3), _aSOFA, _aLactate, and _aNLR can, either alone or in conjunction with the others, improve the mortality prediction beyond that of the effects of age and percentage total body surface area (TBSA%) burned among patients with severe burns who need critical care. This is a retrospective, explorative, single centre, registry study based on prospectively gathered data. The study included 222 patients with median (25th–75th centiles) age of 55.0 (38.0 to 69.0) years, TBSA% burned was 24.5 (13.0 to 37.2) and crude mortality was 17%. As anticipated highest predicting power was obtained with age and TBSA% with an AUC at 0.906 (95% CI 0.857 to 0.955) as compared with EMR, _aSOFA, _aLactate and _aNLR. The largest effect was seen thereafter by adding _aLactate to the model, increasing AUC to 0.938 (0.898 to 0.979) (p < 0.001). Whereafter, adding EMR, _aSOFA, and _aNLR, separately or in combinations, only marginally improved the prediction power. This study shows that the prediction model with age and TBSA% may be improved by adding _aLactate, despite the fact that _aLactate levels were only moderately increased. Thereafter, adding EMR, _aSOFA or _aNLR only marginally affected the mortality prediction.

Meta-Analysis of Renal Replacement Therapy for Burn Patients: Incidence Rate, Mortality, and Renal Outcome

Background: Renal replacement therapy (RRT) was often needed by some severe burn patients with acute kidney injury (AKI). The primary aim of this study was to review incidence rate and mortality of RRT in severe burn patients. Second aims were to review RRT complications and renal outcome.

Methods: We searched multiple databases for studies published between 1 January 1960 and 31 December 2019. Studies about adult populations with burn injury, providing epidemiologic data on prevalence or mortality of RRT, were included.

Results: A total of selected 57 studies, including 27,437 patients were enrolled in our analysis. The prevalence rates of RRT were 8.34% (95% CI 7.18–9.5%) in all burn patients and 37.05% (95% CI 29.85–44.24%) in AKI patients. The mortality of all burn patients with RRT was 65.52% (95% CI 58.41–72.64%). The prevalence rates of RRT in sample size≥100 group were 6.86% (95% CI 5.70–8.03%), which was lower than that of <100 group (17.61%, 95% CI 13.39–21.82%). With the increase of TBSA, the prevalence of RRT may have the increasing trend. The prevalence rates of RRT in Asian group was 12.75% (95% CI 9.50–16.00%), which was higher than that of European (10.45%, 95% CI 7.30–13.61%) and North America group (5.61%, 95% CI 4.27–6.95%). The prevalence rates of RRT in 2010–2019 group was 12.22% (95% CI 10.09–14.35%), which was higher than that of 2009–2000 group (5.17%, 95% CI 2.88–7.46%). The prevalence rates of RRT in 1989 and before group was the lowest, which was 1.56% (95% CI 0–3.68%). However, there was no significant correlation between the year of publication and the mortality of burn patients with RRT. Dialysis-requiring AKI in burn patients could increases the risk of chronic kidney disease progression and end-stage renal disease. About 35% of RRT patients need to maintain haemodialysis temporarily, even if they survive and leave hospital.

Conclusions: The prevalence rate of RRT is about 6–8%; approximately, one-third of burn patients with AKI need RRT. The prevalence rate of RRT increased over time, but the mortality did not change. The prevalence rates of RRT in Asian group was higher than that of European and North America group.

Admission creatinine is associated with poor outcomes in burn patients

INTRODUCTION

Renal failure is the most common organ failure in severely burned patients. However, defining acute kidney injury and renal failure is very challenging. This study was designed to determine the relationship between a biomarker commonly measured on admission, serum creatinine, and outcomes in burn patients.

METHODS

We conducted a retrospective cohort study of adult patients (≥ 18 years) with a burn ≥ 5% total body surface area (TBSA) and a serum creatinine level measured within the first 72 h after injury. Patients were admitted over an 11-year period and divided into two groups based on creatinine levels measured within the first 72 h after injury. Patients were categorized in the high creatinine group if they had a measured creatinine ≥107 μmol/L (≥1.21 mg/dL); this value was chosen as the threshold for creatinine based on our institution's reference range. Clinical outcomes included morbidities, hospital length of stay, and mortality. Multivariable logistic regression was used to model the association between high admission creatinine and each outcome, adjusting for patient and injury characteristics.

RESULTS

We studied 923 patients, mean age 47 ± 18 years and median 13% (IQR 8-24) TBSA burned. There were 718 patients categorized with low admission creatinine and 205 patients with high admission creatinine. After adjustment for patient and injury characteristics, high admission creatinine was associated with a significantly higher rate of sepsis (OR 3.44; 95% CI 2.11-5.59), pneumonia (OR 4.56; 95% CI 1.8-11.53), and mortality (OR 3.59; 95% CI 1.91-6.75).

CONCLUSIONS

Elevated creatinine on admission is associated with an increased risk of morbidity and mortality. We suggest that admission creatinine can be used as a "red flag" to identify patients at a higher risk for poor outcomes.

Protective Effect of Calcium Dobesilate on Induced AKI in Severely Burned Mice

BACKGROUND

Early acute kidney injury (AKI) predicts a high mortality rate in severely burned patients. However, the pathophysiology of early AKI induced by severe burn has not been well-defined. This study was designed to examine the protective effects of calcium dobesilate (CaD) against severe burn-induced early AKI in mice and explore the mechanism.

METHODS

The shaved backs of mice were immersed in 100°C water for 10 s to make severe burn (40% of the total body surface area). CD-57 male mice were randomly divided into sham, burn, burn + vehicle, and burn + CaD groups. Renal function, reactive oxygen species generation, tubular necrosis, and phosphorylation of mitogen-activated protein kinase, protein kinase B (Akt), and nuclear factor (NF)-κB were measured at 24 and 48 h after the burn. Renal histology, ELISA, qRT-PCR, and Western blotting were performed on the renal tissue of mice to examine the effects and mechanisms at 24 and 48 h after the burn.

RESULTS

Tubular damage, cast formation, and elevations of serum creatinine, BUN, and renal tissue kidney injury molecule 1 levels were all observed in the burned mice, and these were all alleviated in the mice with CaD treatment. In addition, the levels of oxidation-reduction potential and malondialdehyde were decreased, while the activities of the endogenous antioxidative enzymes were increased in the kidney tissues from the mice after CaD treatment. Furthermore, the activities of Akt, p38, extracellular sign-regulated kinase, Jun N-terminal kinase, and NF-κB signaling were increased in the kidney of burned mice and normalized after CaD treatment.

CONCLUSION

This study has established, for the first time, the protective effect of CaD against early AKI in severely burned mice. CaD may exert its protective effect through alleviating oxidative stress, apoptosis, and inflammation, as well as modulating some signaling pathways in the kidney.

Early Initiation of Renal Replacement Therapy Among Burned Patients With Acute Kidney Injury

BACKGROUND

Burned patients with acute kidney injury (AKI) requiring renal replacement therapy (RRT) have exceedingly high mortality rates of 73% to 100%. Since January 2011, we have been adopting an early RRT approach in managing burned patients with AKI. Our hypothesis was that early initiation of RRT leads to improved outcome and survival among burned patients with AKI.

METHODOLOGY

We conducted a retrospective analysis of Burns Database in Singapore General Hospital from January 2011 to February 2016. Indications for dialysis included serum creatinine of greater than 1.5 times baseline or urine output of less than 0.5 mL/kg per hour for at least 6 consecutive hours. Patients with similar condition from January 2006 to December 2010 were recruited for comparison.

RESULT

A total of 27 patients with burns and AKI were recruited from January 2011 to February 2016. The mean age was 45.4 years and 88.9% were male. The mean total burn surface area (TBSA) was 54.8%. The total volume of fluid resuscitation was 2.7 mL/kg per TBSA. The time from onset of burn to RRT was 6.4 days. Most patients presented with stage 1 AKI (51.9%), whereas 22.2% and 25.9% had stage 2 and stage 3 AKI, respectively. Most patients (74.1%) received CRRT and 18.5% received SLED. The mortality rate was 37.0% with majority of death (70%) due to sepsis/multiorgan failure. Only 1 patient required long-term RRT after discharge, and there was no occurrence of abdominal compartment syndrome. The mean age of 15 patients from 2006 to 2010 was 47.8 years. The mean TBSA was 49.5%. Only 26.7% of patients were started on RRT. The mortality rate was 66.7%, which was higher than that of subjects from 2011 to 2016 (37.0%) (P = 0.039).

CONCLUSIONS

Optimal timing of RRT for burned patients with AKI has not been established and data on early RRT approach are scarce. The findings of our study suggested that early RRT was associated with lower mortality rates among burned victims with AKI.

Renin signals renal hypoperfusion during Parkland fluid resuscitation of severe burns - a prospective longitudinal cohort study

INTRODUCTION

Previous investigations have shown that fluid resuscitation of burns using the Parkland formula results in controlled hypovolaemia and that kidney injury is a common complication. Enhancing monitoring of tissue perfusion might reduce complications. Plasma renin has recently been suggested to be a promising marker for tissue hypoperfusion in intensive care patients. The aim of this study was to explore plasma renin levels during the first 48 hours after major burns in patients resuscitated using the Parkland formula.

MATERIALS AND METHODS

Patients 18 years or older of age with 10% or more total body surface area (TBSA) burned, admitted to Linköping Burn Intensive Care Unit, and resuscitated using the Parkland formula were included. Samples for plasma renin were drawn at admission and eight-hourly thereafter for 48 hours.

RESULTS

Fifteen patients were included. Median TBSA burned was 36% and age 53 years. The fluid volumes provided were in accordance with the Parkland formula. Mean arterial pressure, urinary output, and lactate remained within reference ranges during the first 48 hours. At eight hours after burn median plasma renin was elevated to more than 25 times the upper reference value, decreasing to about four times the upper reference at 48 hours. Renin concentration was associated with lactate levels and TBSA burned.

CONCLUSION

During Parkland fluid resuscitation of severe burns, plasma renin levels were extremely elevated. The fact that the traditionally used endpoints for Parkland fluid resuscitation remained within the reference range raises concerns about whether the increased renin concentrations may signal a relative renal hypoperfusion.

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.

High Versus Low Volume Fluid Resuscitation Strategies in a Porcine Model (Sus scrofa) of Combined Thermal and Traumatic Brain Injury

BACKGROUND

Combined burn and traumatic brain injury (TBI) treatment priorities may not align due to opposing fluid resuscitation paradigms used in treating burns and TBI. We developed a porcine model of combined thermal injury/TBI and compared an "aggressive" fluid resuscitation strategy using the Parkland formula and a "restrictive" resuscitation strategy using the modified Brooke formula.

METHODS

Twenty-eight swine were deeply anesthetized and received a 40% total body surface area full-thickness burn injury and TBI. Swine were then randomized to receive restrictive or aggressive resuscitation for 8 h after which time animals were euthanized and necropsy was performed. Volume of brain injury was assessed after analyzing segmental slices of brain tissue.

RESULTS

There were no differences between the restrictive and aggressive resuscitation groups in blood pressure, heart rate, central venous pressure, intra-cranial pressure (ICP), or serum lactate levels after 8 h of resuscitation. Urine output was higher in the aggressive resuscitation group. The restrictive group had a significantly higher serum blood urea nitrogen (BUN) compared with baseline and compared with the aggressive group. There was no significant difference in size of brain injury between groups.

CONCLUSIONS

Both restrictive and aggressive resuscitation demonstrated adequate resuscitation at 8 h postinjury. Increased serum BUN in the restrictive group may be an indicator of early acute kidney injury, despite adequate urine output. Resuscitation strategy did not appear to affect ICP or the size of brain injury.

A Combination of Kidney Ischemia and Injection of Isolated Mitochondria Leads to Activation of Inflammation and Increase in Mortality Rate in Rats

We studied the development of acute kidney injury and animal death in the model of combined injury caused by kidney ischemia/reperfusion with simultaneous systemic administration of mitochondria. It was found that intraperitoneal injection of isolated mitochondria led to the appearance of mitochondrial DNA in the peripheral blood that could activate innate immunity. After administration of mitochondria, as well as after renal ischemia/reperfusion, proinflammatory changes were observed, primarily leukocytosis and granulocytosis. The combination of ischemia/reperfusion with injection of mitochondria caused a sharp increase in animal death, which may indicate a direct link between activation of TLR-signaling and high mortality of patients with combined injuries and multiple-organ failure in intensive care units. Treatment with mitochondria-targeted antioxidant increased animal survival, which indicated the participation of mitochondrial ROS in the development of systemic inflammatory response and death caused by acute renal failure.

Long-Term Outcome After Renal Replacement Therapy in Severe Burns

Acute kidney injury is a common sequela after major burn injury, but only a small proportion of patients need renal replacement therapy. In the majority of patients, need for renal replacement therapy subsides before discharge from the burn center but limited literature exists on long-term outcomes. A few studies report an increased risk for chronic renal failure after burn injury. We investigated the long-term outcome of severely burned patients receiving renal replacement therapy during acute burn injury treatment. Data on 68 severely burned patients who received renal replacement therapy in Helsinki Burn Centre between November 1988 and December 2015 were collected retrospectively. Thirty-two patients survived and remained for follow-up after the primary hospital stay until December 31, 2016. About 56.3% of discharged patients were alive at the end of follow-up. In 81.3% of discharged patients, need for renal replacement therapy subsided before discharge. Two patients received renal replacement therapy for longer than 3 months; however, need for renal replacement therapy subsided in both patients. One patient required dialysis several years later on after the need for renal replacement therapy had subsided. This study showed that long-term need for renal replacement therapy is rare after severe burn injury. In the vast majority of patients, need for renal replacement therapy subsided before discharge from primary care. Acute kidney injury in association with burns is a potential but small risk factor for later worsening of kidney function in fragile individuals.

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.

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)

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.

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.

Effects of Diabetes Mellitus on the Mortality, Length of Hospital Stay and Number of Operations in Burn Patients

Background

The effects of diabetes mellitus (DM) on mortality and morbidities in burn patients have not been sufficiently elucidated.

Objective

The present study aimed to investigate the effects of DM on the mortality, length of hospital stay, and number of operations in burn patients.

Methods

A retrospective cohort study was performed using medical records of 3,220 burn patients. Multiple logistic regression, linear regression, and Poisson regression models were used to determine whether DM increases mortality in patients with burn injury, whether DM prolongs length of hospital stay in burn survivors, and whether DM increases the number of operations in burn survivors, respectively.

Results

After adjusting for potential confounding factors, DM significantly increased odds of death in burn patients (adjusted odds ratio 3.225 [95% confidence interval 1.405~7.400], p=0.006). DM also increased the mean length of hospital stay in burn survivors (adjusted mean ratio 1.312 [95% confidence interval 1.198~1.437], p<0.001). Furthermore, DM significantly increased the mean number of operations in burn survivors (adjusted mean ratio 1.576 [95% confidence interval 1.391~1.785], p<0.001).

Conclusion

DM increases mortality, elongates hospital stay and makes more operations required in patients with burn injury.

Predicting wound healing rates and survival with the use of automated serial evaluations of burn wounds

Healing of burn wounds is necessary for survival; however tracking progression or healing of burns is an inexact science. Recently, the relationship of mortality and wound healing has been documented with a software termed WoundFlow. The objective of the current study was to confirm various factors that impact burn wound healing, as well as to establish a timeline and rate of successful healing. A retrospective analysis was performed on adults (n=115) with at least 20% TBSA burn that had at least two computer-based wound mappings. The % open wound (%OW) was calculated over time to document healing trajectory until successful healing or death. Only 2% of patients in the group with successful wound healing died. A decrease in the %OW of 0.8 (IQR: 0.7-1.1) was associated with survival. Disparities in wound healing trajectories between survivors and non-survivors were distinguishable by 2weeks post-injury (P<0.05). When %TBSA was stratified by decile, the 40-49% TBSA group had the highest healing rate. Taken together, the data indicate that wound healing trajectory (%OW) varies with injury severity and survival. As such, automated mapping of wound healing trajectory may provide valuable information concerning patient/prognosis, and may recommend early interventions to optimize wound healing.

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.

Burn injury mortality in patients with preexisting and new onset renal disease

INTRODUCTION

We sought to examine the impact of preexisting and new onset renal disease on burn injury mortality.

METHODS

Retrospective analysis of patients admitted to a regional burn center from 2002-2012 was performed. Variables analyzed included demographics, burn mechanism, inhalation injury status, and % TBSA. Poisson regression was performed to estimate risk of in-hospital burn mortality.

RESULTS

There were a total of 7640 patients over the study period. The adjusted 60-day risk of in-hospital mortality in patients with preexisting renal disease (PRD was 3 times higher compared to patients with no preexisting renal disease (IRR = 3.22, 95% CI = 1.26-8.25). The adjusted 60-day risk of mortality is 2 times higher for patients with new onset renal disease compared to those without (IRR = 2.11, 95% CI = 1.55-2.87).

CONCLUSION

Preexisting and new onset renal disease results in a significantly higher risk of mortality following burn injury compared to patients without renal disease. Prevention of new onset renal injury and careful management of patients with preexisting renal disease to prevent exacerbation should be pursued.

Validation of the burn intervention score in a National Burn Centre

The Linköping burn score has been used for two decades to calculate the cost to the hospital of each burned patient. Our aim was to validate the Burn Score in a dedicated Burn Centre by analysing the associations with burn-specific factors: percentage of total body surface area burned (TBSA%), cause of injury, patients referred from other (non-specialist) centres, and survival, to find out which of these factors resulted in higher scores. Our second aim was to analyse the variation in scores of each category of care (surveillance, respiration, circulation, wound care, mobilisation, laboratory tests, infusions, and operation). We made a retrospective analysis of all burned patients admitted during the period 2000-15. Multivariable regression models were used to analyse predictive factors for an increased daily burn score, the cumulative burn score (the sum of the daily burn scores for each patient) and the total burn score (total sum of burn scores for the whole group throughout the study period) in addition to sub-analysis of the different categories of care that make up the burn score. We retrieved 22301 daily recordings for inpatients. Mobilisation and care of the wound accounted for more than half of the total burn score during the study. Increased TBSA% and age over 45 years were associated with increased cumulative (model R² 0.43, p<0.001) and daily (model R² 0.61, p<0.001) burn scores. Patients who died had higher daily burn scores, while the cumulative burn score decreased with shorter duration of hospital stay (p<0.001). To our knowledge this is the first long term analysis and validation of a system for scoring burn interventions in patients with burns that explores its association with the factors important for outcome. Calculations of costs are based on the score, and it provides an indicator of the nurses' workload. It also gives important information about the different dimensions of the care provided from thorough investigation of the scores for each category.

Hyperphosphatemia is associated with high mortality in severe burns

Introduction

Phosphate level is often deranged during acute illness, regardless of the presence of kidney injury or not. A few studies described that hypophosphatemia may associated with outcome in patients admitted to the burn unit, but the literatures for hyperphosphatemia is limited. Our study aims to evaluate if hyperphosphatemia, one of the sign of severe tissue damage or kidney injury, will associate with mortality of patients with severe burns.

Materials and methods

The study was a post hoc analysis of prospectively collected data from patients admitted to the burn unit between September 2006 and December 2011. Patients were stratified into normophosphatemic or hyperphosphatemic group by baseline plasma phosphate level. The primary endpoint is 90-day mortality.

Results

Total 301 patients were included (hyperphosphatemia: n = 52; normophosphatemia: n = 249). The hyperphosphatemic group had lower Glasgow Coma Scale, mean arterial blood pressure, hemoglobin level, albumin, and higher TBSA of burns, APACHE II score, ABSI score, Acute kidney injury (AKI), and creatinine. The 90-day mortality was higher in the hyperphosphatemic group than in the normal group (53.8% vs 18.1%, P < .001) and this difference was still significant when adjusting for several confounding factors (hazard ratio, 2.05; 95% CI, 1.17–3.59). Multivariable Cox analysis showed risk factors of mortality included TBSA of burns, hyperphosphatemia, reduced urine output, and APACHE II score.

Conclusions

Our study found in addition to TBSA of burns and inhalation injury, baseline hyperphosphatemia in patients with severe burns is also associated with higher mortality.

Co-administration of vancomycin and piperacillin-tazobactam is associated with increased renal dysfunction in adult and pediatric burn patients

Background

Burn patients are prone to infections which often necessitate broad antibiotic coverage. Vancomycin is a common antibiotic after burn injury and is administered alone (V), or in combination with imipenem-cilastin (V/IC) or piperacillin-tazobactam (V/PT). Sparse reports indicate that the combination V/PT is associated with increased renal dysfunction. The purpose of this study was to evaluate the short-term impact of the three antibiotic administration types on renal dysfunction.

Methods

All pediatric and adult patients admitted to our centers between 2004 and 2016 with a burn injury were included in this retrospective review if they met the criteria of exposition to either V, V/IC, or V/PT for at least 48 h, had normal baseline creatinine, and no pre-existing renal dysfunction. Creatinine was monitored for 7 days after initial exposure; the absolute and relative increase was calculated, and patient renal outcomes were classified according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria depending on creatinine increases and estimated creatinine clearance. Secondary endpoints (demographic and clinical data, incidences of septicemia, and renal replacement therapy) were analyzed. Antibiotic doses were modeled in logistic and linear multivariable regression models to predict categorical KDIGO events and relative creatinine increase.

Results

Out of 1449 patients who were screened, 718 met the inclusion criteria, 246 were adults, and 472 were children. Between the study cohorts V, V/IC, and V/PT, patient characteristics at admission were comparable. V/PT administration was associated with a statistically higher serum creatinine, and lower creatinine clearance compared to patients receiving V alone or V/IC in adults and children after burn injury. The incidence of KDIGO stages 1, 2, and 3 was higher after V/PT treatment. In children, the incidence of KDIGO stage 3 following administration of V/PT was greater than after V/IC. In adults, the incidence of renal replacement therapy was higher after V/PT compared with V or V/IC. Multivariate modeling demonstrated that V/PT is an independent predictor of renal dysfunction.

Conclusion

Co-administration of vancomycin and piperacillin-tazobactam is associated with increased renal dysfunction in pediatric and adult burn patients when compared to vancomycin alone or vancomycin plus imipenem-cilastin. The mechanism of this increased nephrotoxicity remains elusive and warrants further scientific evaluation.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1899-3) contains supplementary material, which is available to authorized users.

Acute Kidney Injury in Burn Patients: Clinically Significant Over the Initial Hospitalization and 1 Year After Injury: An Original Retrospective Cohort Study

OBJECTIVE

To examine the development of acute kidney injury (AKI) after burn injury as an independent risk factor for increased morbidity and mortality over initial hospitalization and 1-year follow-up.

BACKGROUND

Variability in fluid resuscitation and difficulty recognizing early sepsis are major barriers to preventing AKI after burn injury. Expanding our understanding of the burden AKI has on the clinical course of burn patients would highlight the need for standardized protocols.

METHODS

We queried the Healthcare Cost and Utilization Project State Inpatient Databases in the states of Florida and New York during the years 2009 to 2013 for patients over age 18 hospitalized with a primary diagnosis of burn injury using ICD-9 codes. We identified and grouped 18,155 patients, including 1476 with burns >20% total body surface area, by presence of AKI. Outcomes were compared in these cohorts via univariate analysis and multivariate logistic regression models.

RESULTS

During initial hospitalization, AKI was associated with increased pulmonary failure, mechanical ventilation, pneumonia, myocardial infarction, length of stay, cost, and mortality, and also a lower likelihood of being discharged home. One year after injury, AKI was associated with development of chronic kidney disease, conversion to chronic dialysis, hospital readmission, and long-term mortality.

CONCLUSIONS

AKI is associated with a profound and severe increase in morbidity and mortality in burn patients during initial hospitalization and up to 1 year after injury. Consensus protocols for initial burn resuscitation and early sepsis recognition and treatment are crucial to avoid the consequences of AKI after burn injury.

Staged excisions of moderate-sized burns compared with total excision with immediate autograft: an evaluation of two strategies

BACKGROUND

Different surgical techniques have evolved since excision and autografting became the treatment of choice for deep burns in the 1970s. The treatment plan at the Burn Center, Linköping University Hospital, Sweden, has shifted from single-stage excision and immediate autografting to staged excisions and temporary cover with xenografts before autografting. The aim of this study was to find out if the change in policy resulted in extended duration of hospital stay/total body surface area burned (LOS/TBSA%).

METHODS

Retrospective clinical cohort including surgically-managed patients with burns of 15%-60% TBSA% within each treatment group. The first had early full excisions of deep dermal and full thickness burns and immediate autografts (1997-98), excision and immediate autograft group) and the second had staged excisions before final autografts using xenografts for temporary cover (2010-11, staged excision group).

RESULTS

The study included 57 patients with deep dermal and full-thickness burns, 28 of whom had excision and immediate autografting, and 29 of whom had staged excisions with xenografting before final autografting. Adjusted (LOS/TBSA%) was close to 1, and did not differ between groups. Mean operating time for the staged excision group was shorter and the excised area/operation was smaller. The total operating time/TBSA% did not differ between groups.

CONCLUSION

Staged excisions with temporary cover did not affect adjusted LOS/TBSA% or total operating time. Staged excisions may be thought to be more expensive because of the cost of covering the wound between stages, but this needs to be further investigated as do the factors that predict long term outcome.

Using acute kidney injury severity and scoring systems to predict outcome in patients with burn injury

BACKGROUND/PURPOSE

Acute kidney injury (AKI) is a frequent complication of severe burn injury and is associated with mortality. The definition of AKI was modified by the Kidney Disease Improving Global Outcomes Group in 2012. So far, no study has compared the outcome accuracy of the new AKI staging guidelines with that of the complex score system. Hence, we compared the accuracy of these approaches in predicting mortality.

METHODS

This was a post hoc analysis of prospectively collected data from an intensive care burn unit in a tertiary care university hospital. Patients admitted to this unit from July 2004 to December 2006 were enrolled. Demographic, clinical, and laboratory data and prognostic risk scores were used as predictors of mortality.

RESULTS

A total of 145 adult patients with a mean age of 41.9 years were studied. Thirty-five patients (24.1%) died during the hospital course. Among the prognostic risk models, the Acute Physiology and Chronic Health Evaluation III system exhibited the strongest discriminative power and the AKI staging system also predicted mortality well (areas under the receiver operating characteristic curve: 0.889 vs. 0.835). Multivariate logistic regression analysis identified total burn surface area, ventilator use, AKI, and toxic epidermal necrolysis as independent risk factors for mortality.

CONCLUSION

Our results revealed that AKI stage has considerable discriminative power for predicting mortality. Compared with other prognostic models, AKI stage is easier to use to assess outcome in patients with severe burn injury.

Early and Late Acute Kidney Injury in Severely Burned Patients

Background

This study evaluated factors influencing early and late occurrence of AKI in severely burned patients and assessed the relationship between time of occurrence of AKI and mortality of AKI patients.

Material/Methods

Renal function was evaluated at 3 time points: at admission, at the critical point or middle point of hospitalization, and at the endpoint for which death or a discharge from the center was considered. AKI criteria were: decrease in GFR of less than 60 ml/min at admission, decrease in GFR of more than 75% compared to baseline, and decrease in the daily diuresis of less than 500 ml/24 h.

Results

At admission, 15.1% of the patients had eGFR <60 ml/min. AKI occurred in 38.5% of cases. The occurrence of AKI was associated with: elderly age (p<0.001), female sex (p=0.017), overweight and obesity (p=0.055); extent and depth of burns, respiratory failure, low protein concentration (for all p<0.001), low blood pressure (p=0.014), and high WBC (p=0.010). Early AKI was detected in 28% of patients. Mortality was 100% with the initial GFR ≥60, 100% with the initial GFR <60 and early deterioration of renal function, 80% with the initial GFR <60 and late worsening, and 60% with the initial GFR <60 and no worsening. Late AKI was observed in 10% of patients and mortality in this group was 79.2%. Mortality in the entire group with AKI was 88.0% versus 24.5%.

Conclusions

The frequent occurrence of AKI, especially early, worsens the prognosis for survival. Assessment of renal function should be included in the prognostic scales for burned patients.

Temporary coverage of burns with a xenograft and sequential excision, compared with total early excision and autograft

During the 80s and 90s, early and total excision of full thickness burns followed by immediate autograft was the most common treatment, with repeated excision and grafting, mostly for failed grafts. It was hypothesized, therefore, that delayed coverage with an autograft preceded by a temporary xenograft after early and sequential smaller excisions would lead to a better wound bed with fewer failed grafts, a smaller donor site, and possibly also a shorter duration of stay in hospital. We carried out a case control study with retrospective analysis from our National Burn Centre registry for the period 1997-2011. Patients who had been managed with early total excision and autograft were compared with those who had had sequential smaller excisions covered with temporary xenografts until the burn was ready for the final autograft. The sequential excision and xenograft group (n=42) required one-third fewer autografts than patients in the total excision and autograft group (n=45), who needed more than one operation (p<0.001). We could not detect any differences in duration of stay in hospital / total body surface area burned% (duration of stay/TBSA%) (2.0 and 1.8) (p=0.83). The two groups showed no major differences in terms of adjusted duration of stay, but our findings suggest that doing early, smaller, sequential excisions using a xenograft for temporary cover can result in shorter operating times, saving us the trouble of making big excisions. However, costs tended to be higher when the burns were > 25% TBSA.

Melatonin prevents acute kidney injury in severely burned rats via the activation of SIRT1

Acute kidney injury (AKI) is a common complication after severe burns. Melatonin has been reported to protect against multiple organ injuries by increasing the expression of SIRT1, a silent information regulator that regulates stress responses, inflammation, cellular senescence and apoptosis. This study aimed to investigate the protective effects of melatonin on renal tissues of burned rats and the role of SIRT1 involving the effects. Rat severely burned model was established, with or without the administration of melatonin and SIRT1 inhibitor. The renal function and histological manifestations were determined to evaluate the severity of kidney injury. The levels of acetylated-p53 (Ac-p53), acetylated-p65 (Ac-p65), NF-κB, acetylated-forkhead box O1 (Ac-FoxO1), Bcl-2 and Bax were analyzed to study the underlying mechanisms. Our results suggested that severe burns could induce acute kidney injury, which could be partially reversed by melatonin. Melatonin attenuated oxidative stress, inflammation and apoptosis accompanied by the increased expression of SIRT1. The protective effects of melatonin were abrogated by the inhibition of SIRT1. In conclusion, we demonstrate that melatonin improves severe burn-induced AKI via the activation of SIRT1 signaling.

Acute Kidney Injury in Critically Injured Combat Veterans: A Retrospective Cohort Study

BACKGROUND

Acute kidney injury (AKI) has been associated with mortality after traumatic injury. However, there is a paucity of data for military service members with injuries received in combat. We sought to identify risk factors for AKI after combat trauma and evaluate whether AKI is a predictor of mortality.

STUDY DESIGN

Retrospective observational study.

SETTINGS & PARTICIPANTS

US service members who were critically wounded in Iraq or Afghanistan from February 1, 2002, to February 1, 2011, and survived until evacuation to Landstuhl Regional Medical Center, Germany.

PREDICTORS

Demographic variables, vital signs, injury severity score, presence of burn injury, and mechanism of injury as defined at the time of initial injury, as well as the presence of AKI ascertained within the first 7 days using KDIGO (Kidney Disease: Improving Global Outcomes) serum creatinine criteria.

OUTCOMES

Logistic regression models were used to identify risk factors for both AKI and death.

RESULTS

Of 6,011 records, 3,807 were included for analysis after excluding patients with missing data. AKI occurred in 474 (12.5%) patients and 112 (2.9%) died. More patients with versus without AKI died (n=62 [13.1%] vs n=50 [1.5%]; P<0.001). After adjustment, AKI was a predictor of mortality (OR, 5.14; 95% CI, 3.33-7.93; P<0.001). Predictors of AKI were age, African American race, injury severity score, amputations, burns, and presenting vital signs.

LIMITATIONS

AKI diagnoses limited to creatinine-based definitions.

CONCLUSIONS

AKI predicted mortality in combat veterans injured in the wars in Iraq and Afghanistan.

Effects of hydrogen-rich saline on early acute kidney injury in severely burned rats by suppressing oxidative stress induced apoptosis and inflammation

Background

Early acute kidney injury (AKI) in severely burned patients predicts a high mortality that is multi-factorial. Hydrogen has been reported to alleviate organ injury via selective quenching of reactive oxygen species. This study investigated the potential protective effects of hydrogen against severe burn-induced early AKI in rats.

Methods

Severe burn were induced via immersing the shaved back of rats into a 100°C bath for 15 s. Fifty-six Sprague–Dawley rats were randomly divided into Sham, Burn + saline, and Burn + hydrogen-rich saline (HS) groups, and renal function and the apoptotic index were measured. Kidney histopathology and immunofluorescence staining, quantitative real-time PCR, ELISA and western blotting were performed on the sera or renal tissues of burned rats to explore the underlying effects and mechanisms at varying time points post burn.

Results

Renal function and tubular apoptosis were improved by HS treatment. In addition, the oxidation–reduction potential and malondialdehyde levels were markedly reduced with HS treatment, whereas endogenous antioxidant enzyme activities were significantly increased. HS also decreased the myeloperoxidase levels and influenced the release of inflammatory mediators in the sera and renal tissues of the burned rats. The regulatory effects of HS included the inhibition of p38, JNK, ERK and NF-κB activation, and an increase in Akt phosphorylation.

Conclusion

Hydrogen can attenuate severe burn-induced early AKI; the mechanisms of protection include the inhibition of oxidative stress induced apoptosis and inflammation, which may be mediated by regulation of the MAPKs, Akt and NF-κB signalling pathways.

Serum cystatin C and microalbuminuria in burn patients with acute kidney injury

BACKGROUND

This study was aimed at evaluating the effectiveness of serum cystatin C and microalbuminuria as diagnostic markers for acute kidney injury (AKI) in major burn patients.

MATERIALS AND METHODS

Major burn adult patients admitted to the burn intensive care unit within 24 h from the onset of injury were enrolled. Serum cystatin C and microalbuminuria (albumin-creatinine ratio, ACR) were obtained at postburn days 1, 3, 7, 14, 21 and 28. The patients were divided into two groups of the AKI group and the nonacute kidney injury group.

RESULTS

A total of 97 patients were enrolled in this study. Acute kidney injury was diagnosed in 40 patients (41.2%) at postburn day 17.3 ± 7.9. The area under the curve of the receiver operating characteristic curve for serum cystatin C was 0.808 (95% CI, 0.711-0.905, P < 0.001) at postburn day 7 and 0.908 (95% CI, 0.843-0.973, P < 0.001) at postburn day 14. The results were 0.610 (95% CI, 0.497-0.724, P = 0.069) for ACR at postburn day 7 and 0.694 (95% CI, 0.589-0.798, P = 0.001) at postburn day 14. The optimal cut-off value of serum cystatin C at postburn day 14 and ACR at postburn day 14 were 0.85 mg/L (sensitivity, 89.5%; specificity, 82.5%) and 41.51 mg/g cre (sensitivity, 60.5%; specificity, 61.4%), respectively. Serum cystatin C at postburn day 14 was the only significant factor in relation to AKI.

CONCLUSIONS

Serum cystatin C is a valuable diagnostic marker, whereas microalbuminuria is a relatively less significant marker for AKI in major burn patients.

Astaxanthin attenuates early acute kidney injury following severe burns in rats by ameliorating oxidative stress and mitochondrial-related apoptosis

Early acute kidney injury (AKI) is a devastating complication in critical burn patients, and it is associated with severe morbidity and mortality. The mechanism of AKI is multifactorial. Astaxanthin (ATX) is a natural compound that is widely distributed in marine organisms; it is a strong antioxidant and exhibits other biological effects that have been well studied in various traumatic injuries and diseases. Hence, we attempted to explore the potential protection of ATX against early post burn AKI and its possible mechanisms of action. The classic severe burn rat model was utilized for the histological and biochemical assessments of the therapeutic value and mechanisms of action of ATX. Upon ATX treatment, renal tubular injury and the levels of serum creatinine and neutrophil gelatinase-associated lipocalin were improved. Furthermore, relief of oxidative stress and tubular apoptosis in rat kidneys post burn was also observed. Additionally, ATX administration increased Akt and Bad phosphorylation and further down-regulated the expression of other downstream pro-apoptotic proteins (cytochrome c and caspase-3/9); these effects were reversed by the PI3K inhibitor LY294002. Moreover, the protective effect of ATX presents a dose-dependent enhancement. The data above suggested that ATX protects against early AKI following severe burns in rats, which was attributed to its ability to ameliorate oxidative stress and inhibit apoptosis by modulating the mitochondrial-apoptotic pathway, regarded as the Akt/Bad/Caspases signalling cascade.

Renal replacement therapy in the ICU: comparison of clinical features and outcomes of patients with acute kidney injury and dialysis-dependent end-stage renal disease

BACKGROUND

The goal of this study is to study clinical features and outcomes of the patients who had renal replacement therapy (RRT) in the intensive care unit (ICU) between 2000 and 2007.

METHODS

We retrospectively studied 222 patients.

RESULTS

Overall ICU mortality and invasive mechanical ventilation (IMV) rates were 58.1 and 61.3 %. The mean APACHE II score was 27.6 ± 8.3. Chronic dialysis (CD) patients formed 45.5 % of the study population. Acute kidney injury (AKI) patients had higher rates of IMV (73 vs. 51.5 %, p = 0.002), cancer (27.8 vs. 7.9 %, p ≤ 0.001) and mortality (67.8 vs. 50.5 %, p = 0.010) than CD patients. AKI patients with normal kidney function (NKF) before ICU admission had poorer prognosis than acute-on-chronic kidney disease (CKD) and CD patients (78.6, 51 and 50.5 %, respectively, p ≤ 0.001). Multivariate analysis showed that IMV (OR, 14.8; 95 % CI, 5.47-40.05; p ≤ 0.001) and having NKF before hospitalization (OR, 2.8; 95 % CI, 1.04-7.37; p = 0.041) were predictors of overall ICU mortality. Additionally, IMV is found as a prognostic factor for both AKI (OR, 18.7; 95 % CI, 4.48-77.72; p ≤ 0.001) and CD patients (OR, 8.14; 95 % CI, 2.01-33.04; p = 0.003), but APACHE II score is meaningful only for CD patients (OR, 1.13; 95 % CI, 1.02-1.26; p = 0.024). The areas under the ROC curves for APACHE II score were 0.52 (95 % CI, 0.39-0.66) for AKI and 0.78 (95 % CI, 0.55-0.89) for CD patients.

CONCLUSION

The observed ICU mortality among patients requiring RRT is high and IMV is associated with mortality. AKI patients have increased mortality compared to CD patients. AKI patients with past NKF have poorer prognosis than acute-on-CKD and CD patients.

Burn intensive care

As a result of continuous development in the treatment of burns, the LD50 (the burn size lethal to 50% of the population) for thermal injuries has risen from 42% total body surface area (TBSA) during the 1940s and 1950s to more than 90% TBSA for young thermally injured patients. This vast improvement in survival is due to simultaneous developments in critical care, advancements in resuscitation, control of infection through early excision, and pharmacologic support of the hypermetabolic response to burns. This article reviews these recent advances and how they influence modern intensive care of burns.