Cervical Spine Injury in Burned Trauma Patients: Incidence, Predictors, and Outcomes

Cervical spine injuries (CIs) carry significant morbidity and mortality; hence, cervical spine immobilization is used liberally in trauma patients, including burns. The incidence, predictors, and outcomes of CI in burn patients are unknown. A retrospective cohort from the National Trauma Data Bank between 2007 and 2012 included all burned patients with and without CI. Predictors of CI were identified by logistic regression. Outcomes with and without CI were compared with Wilcoxon rank sum test. A total of 94,964 patients were identified with burn injuries. The incidence of CI was 0.79% (n = 745). Mechanism of injury, age, and injury severity score (ISS) were significant predictors of CI. Odds of CI were 109.4 (95% CI: 61.2-195.3, P < .0001) for motor vehicle injury, 87.8 (95% CI: 47.0-164.0, P < .0001) for falls, 1.2 (95% CI: 0.6-2.3, P = .66) for fire/flame, and 2.4 (95% CI: 1.0-5.5, P < .0001) for explosion compared with reference of hot object/substance. For every year increase in age, there were 1.02 higher odds of CI (95% CI: 1.01-1.02, P < .0001). For each point increase in ISS, there were 1.05 higher odds of CI (95% CI: 1.04-1.05, P < .0001). Patients with CI had higher mortality (10.3% vs 2.9%, P < .0001), longer total length of stay (12.0 vs 2.0 days, P < .0001), intensive care unit length of stay (4.0 vs 0.0 days, P < .001), and ventilator days (1.0 vs 0.0 days, P < .0001). The incidence of CI in burn patients is low, especially when due to fire, flame, or scalds; however, CI is associated with higher mortality and worse outcomes.

Uncovering a multitude of human glucocorticoid receptor variants: an expansive survey of a single gene

Background

Glucocorticoids are commonly used in the clinical setting for their potent anti-inflammatory effects; however, significant variations in response to treatment have been demonstrated. Although the underlying mechanisms have yet to be fully understood, this variable response may be a result of alterations in human glucocorticoid receptor (hGR) expression and function. In addition to hGRα, the biologically active isoform, a screening of current databases and publications revealed five alternative splice isoforms and hundreds of variants that have been reported to date. Many of these changes in the hGR-coding gene, NR3C1, have been linked to pathophysiology. However, many studies focus on evaluating hGR expression in vitro or detecting previously reported variants.

Results

In this study, blood from healthy volunteers, burn and asthma patients, as well as from peripheral blood mononuclear cells isolated from leukoreduced donor whole blood, were screened for NR3C1 isoforms. We identified more than 1500 variants, including an additional 21 unique splice isoforms which contain 15 new cryptic exons. A dynamic database, named the Universal hGR (UhGR), was created to annotate and visualize the variants.

Conclusion

This identification of naturally occurring and stress-induced hGR isoforms, as well as the establishment of an hGR-specific database, may reveal new patterns or suggest areas of interest that will lead to the improved understanding of the human stress response system.

Electronic supplementary material

The online version of this article (10.1186/s12863-019-0718-z) contains supplementary material, which is available to authorized users.

Building the Burn Physician Workforce for the 21st Century: Report From February 2014 Burns Workforce Conference

American Burn Association Past President Palmer Q. Bessey, MD, orchestrated a Burn Workforce Conference in Washington, DC in February, 2014, with the goal of evaluating the workforce needs for doctors, nurses, and occupational/physical therapists. This report summarizes the issues related to the need for training future surgeons to manage burn patients. General surgery and plastic surgery residents currently have minimal requirements for burn experience during their training. The respective Boards, however, do require knowledge in the management of burn care. The number of surgeons entering burn fellowships is limited to approximately 10 per year and there are only a handful of burn fellowship programs to train future burn surgeons. A survey sent to burn surgeons revealed that the current workforce is aging and needs to a constant supply of new physicians. It is clear that there is a need to formalize burn fellowships and it was felt that the American Burn Association should be responsible for accreditation of those fellowships.

Timing of Laparotomy and Closure in Burn Patients with Abdominal Compartment Syndrome: Effects on Survival

BACKGROUND

Survival of burn patients with abdominal compartment syndrome (ACS) is uniformly reported to be poor, averaging just 16% after laparotomy. We hypothesize that better outcomes can be achieved with a strategy of immediate laparotomy and early fascial closure.

STUDY DESIGN

Patients with burn injury who were diagnosed with ACS between 2005 and 2016 were identified through a search of databases. Data were gathered from electronic medical records. Timing of laparotomy and closure were calculated for each patient. Patients were stratified into predefined groups based on timing of laparotomy, cause of ACS, patient age, and timing of abdominal closure. Survival rates were calculated and compared.

RESULTS

Forty-six patients with burn injury and ACS were identified. Abdominal compartment syndrome developed during initial resuscitation in 27 patients, during perioperative resuscitation in 5 patients, and during an episode of sepsis in 13 patients. Overall survival was 56%. Mean time to laparotomy from diagnosis of ACS was 1 hour 8 minutes (SD 59 minutes). When ACS developed in patients during initial resuscitation, the mean time to laparotomy from hospital admission was 13 hours (SD 7 hours). Survival rate in this group was 70%, and survival rate in patients treated for ACS later in their hospital course was 33% (p = 0.03). Survival among patients whose laparotomy was closed within 48 hours was 100%, and survival among patients whose laparotomy was not closed within 48 hours was 48% (p = 0.01).

CONCLUSIONS

Immediate laparotomy resulted in much higher survival rates than previously reported in burn patients with ACS. Survival was higher when ACS was diagnosed during initial resuscitation. Fascial closure within 48 hours was associated with improved survival compared with later fascial closure.

Sodium variability is associated with increased mortality in severe burn injury

BACKGROUND

Dysnatremias are associated with increased mortality in critically ill patients. Hypernatremia in burn patients is also associated with poor survival. Based on these findings, we hypothesized that high plasma sodium variability is a marker for increased mortality in severely burn-injured patients.

METHODS

We performed a retrospective review of adult burn patients with a burn injury of 15% total body surface area (TBSA) or greater from 2010 to 2014. All patients included in the study had at least three serum sodium levels checked during admission. We used multivariate logistic regression analysis to determine if hypernatremia, hyponatremia, or sodium variability independently increased the odds ratio (OR) for death.

RESULTS

Two hundred twelve patients met entry criteria. Mean age and %TBSA for the study was 45 ± 18 years and 32 ± 19%. Twenty-nine patients died for a mortality rate of 14%. Serum sodium was measured 10,310 times overall. The median number of serum sodium measurements per patient was 22. Non-survivors were older (59 ± 19 vs. 42 ± 16 years) and suffered from a more severe burn injury (50 ± 25% vs. 29 ± 16%TBSA). While mean sodium was significantly higher for non-survivors (138 ± 3 milliequivalents/liter (meq/l)) than for survivors (135 ± 2 meq/l), mean sodium levels remained within the laboratory reference range (135 to 145 meq/l) for both groups. Non-survivors had a significantly higher median number of hypernatremic (> 145 meq/l) measurements (2 vs. 0). Coefficient of variation (CV) was significantly higher in non-survivors (2.85 ± 1.1) than survivors (2.0 ± 0.7). Adjusting for TBSA, age, ventilator days, and intensive care unit (ICU) stay, a higher CV of sodium measurements was associated with mortality (OR 5.8 (95% confidence interval (CI) 1.5 to 22)). Additionally, large variation in sodium ranges in the first 10 days of admission may be associated with increased mortality (OR 1.35 (95% CI 1.06 to1.7)).

CONCLUSIONS

Increased variability in plasma sodium may be associated with death in severely burned patients.

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

Sepsis has recently been defined as "life-threatening organ dysfunction caused by a dysregulated host response to infection". A great amount of effort has been made to develop early treatments for sepsis through the Surviving Sepsis Campaign. There are similar but slightly different recommendations for the treatment of sepsis in the pediatric population. These international efforts have led to earlier diagnosis and treatments for sepsis that have led to improvements in survival. Sepsis is also the leading cause of death in the burn patient but most clinical sepsis studies have excluded burns. The reason for the exclusion is that the sepsis found in burn patients is different than that of the general population. The early treatment strategies, such as those directed by the Surviving Sepsis Campaign, focus on patients presenting to hospitals with recent signs of infection. Burn patients lose their primary barrier to infection, the skin, and thus the risk of infection persists as long as that barrier is absent. Efforts have been made to define sepsis, septic shock and infection in the burn population but there is constant need for revisions. One focus of this review is to discuss the differences in burn sepsis versus sepsis of the general population. Children often have profound responses to sepsis but can also make remarkable recoveries. This review will also explore problems specific to pediatric burns. The treatment of burns requires a continuous vigilance to watch for the subtle early signs of sepsis and then expeditious initiation of aggressive therapy. Strategies covering optimal management of pediatric burn sepsis will also be summarized.

A novel human glucocorticoid receptor SNP results in increased transactivation potential

Glucocorticoids are one of the most widely used therapeutics in the treatment of a variety of inflammatory disorders. However, it is known that there are variable patient responses to glucocorticoid treatment; there are responders and non-responders, or those that need higher dosages. Polymorphisms in the glucocorticoid receptor (GR) have been implicated in this variability. In this study, ninety-seven volunteers were surveyed for polymorphisms in the human GR-alpha (hGRα), the accepted biologically active reference isoform. One isoform identified in our survey, named hGR DL-2, had four single nucleotide polymorphisms (SNPs), one synonymous and three non-synonymous, and a four base pair deletion resulting in a frame shift and early termination to produce a 743 amino acid putative protein. hGR DL-2 had a decrease in transactivation potential of more than 90%. Upon further analysis of the individual SNPs and deletion, one SNP, A829G, which results in a lysine to glutamic acid amino acid change at position 277, was found to increase the transactivation potential of hGR more than eight times the full-length reference. Furthermore, the hGRα-A829G isoform had a differential hyperactive response to various exogenous steroids. Increasing our knowledge as to how various SNPs affect hGR activity may help in understanding the unpredictable patient response to steroid treatment, and is a step towards personalizing patient care.

Inherently variable responses to glucocorticoid stress among endogenous retroviruses isolated from 23 mouse strains

Active participation of endogenous retroviruses (ERVs) in disease processes has been exemplified by the finding that the HERV (human ERV)-W envelope protein is involved in the pathogenesis of multiple sclerosis, an autoimmune disease. We also demonstrated that injury-elicited stressors alter the expression of murine ERVs (MuERVs), both murine leukemia virus-type and mouse mammary tumor virus (MMTV)-type (MMTV-MuERV). In this study, to evaluate MMTV-MuERVs' responses to stress (e.g., injury, infection)-elicited systemic glucocorticoid (GC) levels, we examined the GC-stress response of 64 MMTV-MuERV promoters isolated from the genomes of 23 mouse strains. All 64 promoters responded to treatment with a synthetic GC, dexamethasone (DEX), at a wide range from a 0.6- to 85.7-fold increase in reporter activity compared to no treatment. An analysis of the 10 lowest and 10 highest DEX responders revealed specific promoter elements exclusively present in either the three lowest or the two highest responders. Each promoter had a unique profile of transcription regulatory elements and the glucocorticoid response element (GRE) was identified in all promoters with the number of GREs ranging from 2 to 7. The three lowest DEX responders were the only promoters with two GREs. The findings from this study suggest that certain MMTV-MuERVs are more responsive to stress-elicited systemic GC elevation compared to the others. The mouse strain-specific genomic MMTV-MuERV profiles and individual MMTV-MuERVs' differential responses to GC-stress might explain, at least in part, the variable inflammatory responses to injury and/or infection, often observed among different mouse strains. This article is part of a Special Issue entitled: Immune and Metabolic Alterations in Trauma and Sepsis edited by Dr. Raghavan Raju.

Real-Time Prediction for Burn Length of Stay Via Median Residual Hospital Length of Stay Methodology

Hospital length of stay (LOS) after burn injury is commonly estimated as 1 day per percent burn, but LOS often exceeds that estimate. The purpose of this study is to develop a novel method for estimating burn hospital LOS at any time during hospitalization. The authors used the American Burn Association National Burn Repository from 2000 to 2009 to directly estimate the median residual LOS (MRLOS) of patients hospitalized for burn injuries and who survived to discharge. The MRLOS is the median of how many more days a burn patient will be hospitalized given that the person has been in hospital for a specified time period. The authors also estimated the 25th and 75th percentiles of residual life and quantified the relationship between MRLOS and LOS with ordinary least squares for all burn patients, by burn size and by presence of inhalation injury. MRLOS increased with increasing LOS, confirming that discharge estimates change over time. Patients with inhalation injury had longer MRLOS than patients without inhalation injury in the first 100 hospital days. Patients with large burns (>25%) had large MRLOS consistent with prolonged hospitalization, but patients with small burns (<25%) also had steadily increasing MRLOS during hospitalization (ie, the longer the patient was in the hospital, the longer the predicted LOS regardless of initial LOS estimate). Estimating remaining hospital LOS at any time during admission has been problematic; MRLOS can be used to provide an estimate of remaining hospital LOS and resource utilization to families, administrators, and other medical professionals.

A competing risk analysis for hospital length of stay in patients with burns

IMPORTANCE

Current outcome predictors for illness and injury are measured at a single time point-admission. However, patient prognosis often changes during hospitalization, limiting the usefulness of those predictions. Accurate depiction of the dynamic interaction between competing events during hospitalization may enable real-time outcome assessment.

OBJECTIVE

To determine how the effects of burn outcome predictors (ie, age, total body surface area burn, and inhalation injury) and the outcomes of interest (ie, mortality and length of stay) vary as a function of time throughout hospitalization.

DESIGN, SETTING, AND PARTICIPANTS

In this retrospective study, we used the American Burn Association's National Burn Repository, containing outcomes and patient and injury characteristics, to identify 95 579 patients admitted with an acute burn injury to 80 tertiary American Burn Association burn centers from 2000 through 2009. We applied competing risk statistical methods to analyze patient outcomes.

MAIN OUTCOMES AND MEASURES

We estimated the cause-specific hazard rates for death and discharge to assess how the instantaneous risk of these events changed across time. We further evaluated the varying effects of patient age, total body surface area burn, and inhalation injury on the probability of discharge and death across time.

RESULTS

Maximum length of stay among patients who died was 270 days and 731 days among those discharged. Total body surface area, age, and inhalation injury had significant effects on the subdistribution hazard for discharge (P < .001); these effects varied across time (P < .002). Burn size (coefficient -0.046) determined early outcomes, while age (coefficient -0.034) determined outcomes later in the hospitalization. Inhalation injury (coefficient -0.622) played a variable role in survival and hospital length of stay.

CONCLUSIONS AND RELEVANCE

Real-time measurement of dynamic interrelationships among burn outcome predictors using competing risk analysis demonstrated that the key factors influencing outcomes differed throughout hospitalization. Further application of this analytic technique to other injury or illness types may improve assessment of outcomes.

Predicting mortality from burns: the need for age-group specific models

Traditional burn mortality models are derived using all age groups. We hypothesized that age variably impacts mortality after burn and that age-specific models for children, adults, and seniors will more accurately predict mortality than an all-ages model. We audited data from the American Burn Association (ABA) National Burn Repository (NBR) from 2000 to 2009 and used mixed effect logistic regression models to assess the influence of age, total body surface area (TBSA) burn, and inhalation injury on mortality. Mortality models were constructed for all ages and age-specific models: children (<18 years), adults (18-60 years), and seniors (>60 years). Model performance was assessed by area under the receiver operating curve (AUC). Main effect and two-way interactions were used to construct age-group specific mortality models. Each age-specific model was compared to the All Ages model. Of 286,293 records 100,051 had complete data. Overall mortality was 4% but varied by age (17% seniors, <1% children). Age, TBSA, and inhalation injury were significant mortality predictors for all models (p<0.05). Differences in predicted mortality between the All Ages model and the age-specific models occurred in children and seniors. In the age-specific pediatric model, predicted mortality decreased with age; inhalation injury had greater effect on mortality than in the All Ages model. In the senior model mortality increased with age. Seniors had greater increase in mortality per 1% increment in burn size and 1 year increase in age than other ages. The predicted mortality in seniors using the senior-specific model was higher than in the All Ages model. "One size fits all" models for predicting burn outcomes do not accurately reflect the outcomes for seniors and children. Age-specific models for children and seniors may be advisable.

Redefining the outcomes to resources ratio for burn patient triage in a mass casualty

Recent disasters highlight the need for predisaster planning, including the need for accurate triage. Data-driven triage tables, such as that generated from the 2002 National Burn Repository, are vital to optimize resource use during a disaster. The study purpose was to generate a burn resource disaster triage table based on current burn-treatment outcomes. Data from the NBR after the year 2000 were audited. Records that missed age, burn size, or survival status were excluded from analysis. Duplicate records, readmissions, transfers, and nonburn injuries were eliminated. Resource use was divided into expectant (predicted mortality >90%), low (mortality 50-90%), medium (mortality 10-50%), high (mortality <10%, admission 14-21 days), very high (mortality <10%, admission <14 days), and outpatient. Tables were created for all patient admissions and with/without inhalation injury. Of the 286,293 records, 210,683 were from the year 2000 or later. Expectant status for those aged >70 years began at 50% burn; a 20- to 29-year-old never reached expectant status. Inhalation injury lowered the expectant category to a burn size of 40% in >70-year-olds, and at >90% in 20- to 29-year-olds. The 0- to 1.9-year old group without inhalation injury never reached expectant status; with inhalation injury, expectant status was reached at >80% burn. Changes in the triage tables suggest that burn care has changed in the past 10 years. Inhalation injury significantly alters triage in a burn disaster. Use of these updated tables for triage in a disaster may improve our ability to allocate resources.

A ten-year review of lower extremity burns in diabetics: small burns that lead to major problems

Diabetes mellitus with its resulting neurovascular changes may lead to an increased risk of burns and impaired wound healing. The purpose of this article is to review 10 years of experience with foot and lower leg burns in patients with diabetes at a single adult burn center. Patients with lower extremity burns and diabetes mellitus, between May 1999 and December 2009, were identified in the Trauma Registry of the American College of Surgeons database, and their charts were reviewed for data related to their outcomes. Sixty-eight diabetic patients, 87% male, with a mean age of 54 years, sustained foot or lower extremity burns with 37 having burns resulting from insensate feet. The pathogenesis included walking on a hot or very cold surface (8), soaking feet in hot water (22), warming feet on or near something hot such as a heater (13), or spilling hot water (7). The majority of patients were taking insulin (59.6%) or oral hyperglycemic medications (34.6%). Blood sugar levels were not well controlled (mean glucose, 215.8 mg/dl; mean hemoglobin A1c, 9.08%). Renal disease was common with admission serum blood urea nitrogen (27.5 mg/dl) and creatinine (2.21 mg/dl), and 13 were on dialysis preinjury. Cardiovascular problems were common with 39 (57%) having hypertension or cardiac disease, 3 having peripheral vascular disease, and 9, previous amputations. The mean burn size was 4.2% TBSA (range, 0.5-15%) with 57% being full thickness. Despite the small burn, the mean length of stay was 15.2 days (range, 1-95), with 5.65 days per 1% TBSA. Inability to heal these wounds was evident in 19 patients requiring readmission (one required 10 operative procedures). At least one patient sustained more than one burn. There were 62 complications with 30 episodes of infection (cellulitis, 28; osteomyelitis, 4; deep plantar infections, 2; ruptured Achilles tendon, 1) and 3 deaths. Eleven patients needed amputations (7 below-knee amputations, 4 transmetatarsal amputations, and 20 toe amputations) with several needing revisions or higher amputations. Patients with diabetes have an increased risk for lower extremity complications, but the risk of burns is not well known. The majority of lower extremity burns result from intentional exposure to sources of heat without recognition for the risk of burns. Once a burn occurs, morbidity and cost to the patient and society are severe. Prevention programs should be initiated to make diabetic patients and their doctors aware of the significant risk for burns.

Identification of a group of Mus dunni endogenous virus-like endogenous retroviruses from the C57BL/6J mouse genome: proviral genomes, strain distribution, expression characteristics, and genomic integration profile

About 10 % of the mouse genome is occupied by sequences associated with endogenous retroviruses (ERVs). However, a comprehensive profile of the mouse ERVs and related elements has not been established yet. In this study, we identified a group of ERVs from the mouse genome and characterized their biological properties. Using a custom ERV mining protocol, 191 ERVs (159 loci reported previously and 32 new loci), tentatively named Mus dunni endogenous virus (MDEV)-like ERVs (MDL-ERVs), were mapped on the C57BL/6J mouse genome. Seven of them retained putative full coding potentials for three retroviral polypeptides (gag, pol, and env). Among the 57 mouse strains examined, all but the Mus pahari/Ei strain had PCR amplicons corresponding to a conserved MDL-ERV region. Interestingly, the Mus caroli/EiJ's amplicon was somewhat larger than the others, coinciding with a substantial phylogenetic distance between the MDL-ERV populations of M. caroli/EiJ and C57BL/6J strains. MDL-ERVs were highly expressed in the lung, spleen, and thymus of C57BL/6J mice compared to the brain, heart, kidney, and liver. Seven MDL-ERVs were mapped in the introns of six annotated genes. Of interest, some MDL-ERVs were mapped periodically on three clusters in chromosome X. The finding that these MDL-ERVs were one of several types of retroelements, which form mosaic-repeat units of tandem arrays, suggests that the formation of the mosaic-repeat unit preceded the tandem arrangement event. Further studies are warranted to understand the biological roles of MDL-ERVs in both normal and pathologic conditions.

ERE database: a database of genomic maps and biological properties of endogenous retroviral elements in the C57BL/6J mouse genome

Endogenous retroviral elements (EREs), a family of transposable elements, constitute a substantial fraction of mammalian genomes. It is expected that profiles of the ERE sequences and their genomic locations are unique for each individual. Comprehensive characterization of the EREs' genomic locations and their biological properties is essential for understanding their roles in the pathophysiology of the host. In this study, we identified and mapped putative EREs (a total of 111 endogenous retroviruses [ERVs] and 488 solo long terminal repeats [sLTRs]) within the C57BL/6J mouse genome. The biological properties of individual ERE isolates (both ERVs and sLTRs) were then characterized in the following aspects: transcription potential, tropism trait, coding potential, recombination event, integration age, and primer binding site for replication. In addition, a suite of database management system programs was developed to organize and update the data acquired from current and future studies and to make the data accessible via internet.