Early Enteral Nutrition for Burn Injury

Higher energy delivery is associated with improved long-term survival among adults with major burn injury: A multicenter, multinational, observational study

BACKGROUND

Numerous feeding strategies have been used to mitigate the catabolism of major burn injury. Whether higher energy and/or protein delivery results in better long-term outcomes is unknown.

METHODS

We performed a secondary analysis of data from adults with major burn injuries enrolled in the Randomized Trial of Enteral Glutamine to Minimize the Effects of Burn Injury at 54 burn centers in 18 countries. The sample was restricted to those who were mechanically ventilated within 72 hours of injury and for ≥7 days. Our key exposure was adequacy of energy, and protein ([Delivered i /Prescribed i ] × 100) was categorized into three groups each: low, 0% to 50%; moderate, ≥50% to 79%; and high, ≥80%. We also analyzed adequacy using restricted cubic splines. Primary and secondary outcomes included 6-month mortality and functional outcomes (i.e., 36-Item Short-Form Health Survey, Katz Index of Independence in Activities of Daily Living, Lawton Activities of Daily Living scores), respectively. Regression models were adjusted for age, body mass index, Charlson Comorbidity Index, baseline Acute Physiology and Chronic Health Evaluation II and modified Sequential Organ Failure Assessment scores, burn size, energy/protein adequacy, and study site.

RESULTS

A total of 493 participants met the cohort restriction criteria; 336 participants were alive at 6 months. 36-Item Short-Form Health Survey, Katz Index of Independence in Activities of Daily Living, and Lawton Instrumental Activities of Daily Living Scale were completed by 218, 216, and 215 participants, respectively. The mean ± SD age was 48 ± 17 years, and 74% were male. The mean ± SD burn size was 41% ± 18% total body surface area. Participants who received 25% of recommended calories had nearly four times the hazard of death during the 6-month follow-up period than participants who received 100% of prescribed calories (adjusted hazard ratio, 3.89; 95% confidence interval, 1.35-11.20) ( p = 0.02). There was no significant association between protein and 6-month mortality or energy/protein delivery and 6-month functional outcomes.

CONCLUSION

There was a positive association between higher doses of energy and 6-month survival. This relationship conflicts somewhat with several energy studies among critically ill and non-burn-injured patients. The lack of consistent evidence on optimal nutrition for critically injured patients, a fundamental component of burn care, suggests potential for a randomized trial of lower versus higher energy to improve long-term outcomes after burn injury.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Development and validation of a risk prediction model for feeding intolerance in neurocritical patients with enteral nutrition

Background

This study collects and analyzes clinical data on enteral nutrition therapy in neurocritical patients, develops and validates a feeding intolerance (FI) risk prediction model, and provides a theoretical basis for screening patients with high risk of feeding intolerance (FI) and delivering personalized care.

Methods

A convenience sampling method was employed to select 300 patients who were admitted to a tertiary hospital in China for early enteral nutrition therapy in the neurointensive care unit between April 2022 and December 2022. Independent risk factors for FI were identified using univariate and logistic regression analyses. A prediction model was established, and the goodness of fit and discriminant validity of the model were evaluated.

Results

The incidence of FI in neurocritical patients receiving enteral nutrition was 71%. Logistic regression analysis identified age, Glasgow Coma Scale (GCS) scores, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, mechanical ventilation, feeding via the nasogastric tube route, hyperglycemia, and low serum albumin as independent risk factors for the development of FI (p < 0.05). The predictive formula for FI risk was established as follows: Logit p = -14.737 + 1.184 × mechanical ventilation +2.309 × feeding route +1.650 × age + 1.336 × GCS tertile (6-8 points) + 1.696 × GCS tertile (3-5 points) + 1.753 × APACHE II score + 1.683 × blood glucose value +1.954 × serum albumin concentration. The Hosmer-Lemeshow test showed χ2  = 9.622, p = 0.293, and the area under the ROC curve was 0.941 (95% confidence interval: 0.912-0.970, p < 0.001). The optimal critical value was 0.767, with a sensitivity of 85.9%, a specificity of 90.8%, and a Youden index of 0.715.

Conclusion

The early enteral nutrition FI risk prediction model developed in this study demonstrated good predictive ability. This model can serve as a valuable reference for effectively assessing the risk of FI in neurocritical patients, thereby enhancing clinical outcomes.

Effect of three different exercise trainings on functional capacity in early stage severe burn patients: A randomized controlled trial

BACKGROUND

This study investigated the effects of three different exercise protocols on functional capacity in early-stage burn patients.

METHODS

A total of 25 patients hospitalized in the Burn Center (wards and intensive care unit) were included in the study. The individuals were divided into three groups by covariate adaptive randomization according to burn percentage and type: 1 - standard treatment, 2 - standard treatment + aerobic exercise training, 3 - standard treatment + combined exercise (aerobic and resistance) determined by metabolic status. Individuals were evaluated weekly for six weeks from the first day of hospitalization using the 6-minute walk test, physiological cost index, and Medical Research Council muscle-strength measurements to assess functional capacity. A portable metabolism tracker device measured the metabolic status of all patients.

RESULTS

Aerobic exercises and combined exercise (aerobic and resistance), when added to standard treatment and determined by metabolic status, were more effective in enhancing functional capacity than standard treatment alone (p<0.05). Patients performing the combined exercise (aerobic and resistance) showed faster improvement in functional capacity determined according to metabolic status than those in the other two groups (p<0.05).

CONCLUSION

Aerobic exercises, when added to standard treatment and combined with aerobic and resistance exercises based on metabolic status, are more effective at improving functional capacity than standard treatment alone. Further controlled studies are required to explore the potential long-term benefits of this approach.

Impact of an enteral nutrition protocol in critically ill patients with burn injuries

OBJECTIVES

The objective of this study is to characterize the University of Florida (UF) Health Shands Burn Centers enteral nutrition protocol as it relates to total protein intake and clinical outcomes.

METHODS

This retrospective chart review study included 99 adult patients admitted to the UF Health Shands Burn Center from January 2012 through August 2016 with burns of twenty percent or greater TBSA and required enteral nutrition supplementation.

RESULTS

Patients received an average of 137.8 g or 2.03 g/kg protein daily. Fifteen percent of patients experienced graft loss. The median length of stay was 35 days. Seventy-six percent survived to hospital discharge. There was no significant association between total protein intake and incidence of severe diarrhea (P=0.132).

CONCLUSION

The institutions protocol achieved high protein administration while still being consistent with recommendations from the American Society of Enteral and Parenteral Nutrition (ASPEN).

Optimizing Nutritional Needs of Burn Patients: An Evaluation of Nutritional Assessment Tools, Feeding Strategies, and Their Impact on Patient Outcomes

BACKGROUND

Optimal nutritional support is essential to the recovery and improved outcomes of burn patients. This review aims to explore existing literature to evaluate nutrition assessment tools, feeding formulations' caloric predictive ability, timing of initiation of feeding, optimal nutritional composition, and caloric intake in burn patients.

METHODS

Three databases were searched to glean studies investigating nutrition in acute severe adult burn patient populations in four areas: outcomes based on feeding type and timing, the caloric predictability of nutritional assessment tools, outcomes associated with the composition of feeding formulas, and considerations related to caloric intake. Outcomes of interest included the effects of nutritional assessments using feeding type, nutritional administration timing, formula composition, and caloric intake on mortality rate, length of stay, and infection.

RESULTS

A total of 19 studies were included. Nutritional assessment tools were determined to over- or underestimate resting energy expenditure (REE). Milner was the most accurate alternative to indirect calorimetry. Early enteral nutrition in burn patients within 24 hours of admission was preferred. 5 studies evaluated micronutrients and yielded variable results. Low-fat high-carbohydrate diets were the ideal macronutrient composition. Burn patients were shown to receive lower caloric intake than recommended.

CONCLUSIONS

Findings showed that while nutritional assessment tools tend to inaccurately estimate REE in burn patients, the ideal alternative to indirect calorimetry is the Milner equation. Several new equations may be worthy alternatives but require further validation. Enteral feeding should be initiated within the first 24 hours of burn injury whenever possible and should contain a high-carbohydrate/low-fat composition.

Effect of anti-gravity treadmill (Alter G) training on gait characteristics and postural stability in adult with healed burns: A single blinded randomized controlled trial

BACKGROUND

Burns constitute one of the foremost contributors to premature mortality and morbidity, and the recovery process from burn injuries is characterized by its intricate and protracted nature.

OBJECTIVE

The principal aim of this study was to assess the influence of an anti-gravity treadmill (Alter G) training program on both gait characteristics and postural stability indices (PSI) in adult individuals who have recovered from burns.

DESIGN

This study followed a single-blind, randomized, controlled design.

METHODS

A total of 45 adults, aged 18-35 years, with healed lower extremity burns that were circumferential and encompassed 35-50% of their total body surface area (TBSA) were randomly allocated to either the anti-gravity treadmill (Alter G) Training group (n = 22) or the traditional physical therapy program (TPTP) group (n=23). The TPTP group received conventional physical therapy, while the anti-gravity treadmill (Alter G) training group engaged in anti-gravity treadmill exercises alongside the traditional physical therapy program. The primary outcome measures, evaluated at both baseline and the conclusion of the 12-week intervention, included gait characteristics assessed using the GAITRite system and PSI measured by the Biodex Balance System (BBS).

RESULTS

The anti-gravity treadmill (Alter G) training group exhibited significantly greater enhancements than the TPTP group in terms of mean values and percentage changes in gait characteristics and PSI. Specifically, the percentage changes for the Alter G group were as follows: stride length (20.57%), step time (22.58%), step length (20.47%), velocity (15.67%), cadence (23.28%), and double support time (29.03%). In contrast, the TPTP group's percentage changes were: 6.73%, 8.19%, 7.65%, 7.75%, 8.89%, and 9.37%, respectively. Concerning PSI, the Alter G group exhibited percentage changes of 55.17% for the medio-lateral stability index (MLI), 48.21% for antero-posterior stability index (API), and 48.48% for the overall stability index (OSI). The TPTP group's corresponding percentage changes were 20%, 14.03%, and 16.41%.

CONCLUSIONS

The amalgamation of anti-gravity treadmill training with the traditional physical therapy program yields greater efficacy than TPTP in isolation. Consequently, the findings underscore the efficiency of anti-gravity treadmill (Alter G) Training as a valuable tool for rehabilitating patients with burn injuries.

The Role of Vitamin E in Thermal Burn Injuries, Infection, and Sepsis: A Review

Thermal burn injuries are still a serious public health concern in the United States, due to the initial insult and resulting comorbidities. Burned patients are increasingly susceptible to colonization by endogenous and exogenous microorganisms after having lost skin, which acts as the primary protective barrier to environmental contaminants. Furthermore, the onset of additional pathophysiologies, specifically sepsis, becomes more likely in burned patients compared to other injuries. Despite improvements in the early care of burn patients, infections, and sepsis, these pathophysiologies remain major causes of morbidity and mortality and warrant further investigation of potential therapies. Vitamin E may be one such therapy. We aimed to identify publications of studies that evaluated the effectiveness of vitamin E as it pertains to thermal burn injuries, infection, and sepsis. Several investigations ranging from in vitro bench work to clinical studies have examined the impact on, or influence of, vitamin E in vitro, in vivo, and in the clinical setting. To the benefit of subjects it has been shown that enteral or parenteral vitamin E supplementation can prevent, mitigate, and even reverse the effects of thermal burn injuries, infection, and sepsis. Therefore, a large-scale prospective observational study to assess the potential benefits of vitamin E supplementation in patients is warranted and could result in clinical care practice paradigm changes.

Soluble Expression, One-Step Purification and Characterization of Recombinant Human Growth Hormone Fused with ompA3 in Escherichia coli

BACKGROUND

Human growth hormone (hGH) is the first recombinant protein approved for the treatment of human growth hormone deficiency. However, expression in inclusion bodies and low expression levels are enormous challenges for heterologous expression of hGH in Escherichia coli.

OBJECTIVE

To increase the soluble expression of recombinant hGH with correct folding in E. coli.

METHODS

We constructed a new recombinant expression plasmid containing the coding sequence of the outer membrane protein A (ompA3) which was used for the expression in Transetta (DE3) E. coli. In order to simplify the purification process and cleavage of recombinant proteins, the fusion sequence should contain hexahistidine-tag (His₆) and enterokinase recognition sites (D₄K). The effect of different expression conditions on recombinant hGH expression was optimized in flask cultivations. Furthermore, the periplasmic solution containing soluble hGH was purified by Ni-NTA affinity chromatography. Circular dichroism (CD), western blot and mass spectrometry analyses were used to characterize the protein. Moreover, the growth-promoting effect of the purified hGH was also evaluated by cell proliferation assay.

RESULTS

High-level expression (800 μg/mL) was achieved by induction with 0.5 mM IPTG at 30°C for 10 hours. The purity of hGH was over 90%. The immunological activity, secondary structure and molecular weight of the purified hGH were consistent with native hGH. The purified hGH was found to promote the growth of MC3T3-E1 cells, and was found to show the highest activity at a concentration of 100 ng/mL.

CONCLUSION

Our research provides a feasible and convenient method for the soluble expression of recombinant hGH in E. coli, and may lay a foundation for the production and application of hGH in the industry.

Evaluation of Pseudomonas aeruginosa pathogenesis and therapeutics in military-relevant animal infection models

Modern combat-related injuries are often associated with acute polytrauma. As a consequence of severe combat-related injuries, a dysregulated immune response results in serious infectious complications. The gram-negative bacterium Pseudomonas aeruginosa is an opportunistic pathogen that often causes life-threatening bloodstream, lung, bone, urinary tract, and wound infections following combat-related injuries. The rise in the number of multidrug-resistant P. aeruginosa strains has elevated its importance to civilian clinicians and military medicine. Development of novel therapeutics and treatment options for P. aeruginosa infections is urgently needed. During the process of drug discovery and therapeutic testing, in vivo testing in animal models is a critical step in the bench-to-bedside approach, and required for Food and Drug Administration approval. Here, we review current and past literature with a focus on combat injury-relevant animal models often used to understand infection development, the interplay between P. aeruginosa and the host, and evaluation of novel treatments. Specifically, this review focuses on the following animal infection models: wound, burn, bone, lung, urinary tract, foreign body, and sepsis.

Burns: modified metabolism and the nuances of nutrition therapy

OBJECTIVE

To review the effects of burn injury on nutritional requirements and how this can best be supported in a healthcare setting.

METHOD

A literature search for articles discussing nutrition and/or metabolism following burn injury was carried out. PubMed, Embase and Web of Science databases were searched using the key search terms 'nutrition' OR 'metabolism' AND 'burn injury' OR 'burns'. There was no limitation on the year of publication.

RESULTS

A total of nine articles met the inclusion criteria, the contents of which are discussed in this manuscript.

CONCLUSION

Thermal injury elicits the greatest metabolic response, among all traumatic events, in critically ill patients. In order to ensure burn patients can meet the demands of their increased metabolic rate and energy expenditure, adequate nutritional support is essential. Burn injury results in a unique pathophysiology, involving alterations in endocrine, inflammatory, metabolic and immune pathways and nutritional support needed during the inpatient stay varies depending on burn severity and idiosyncratic patient physiologic parameters.

Nutrition: reducing the hypermetabolic response to thermal injury

Nutritional support is seen as a vital component in the battle to attenuate the extreme hypermetabolic response experienced by patients suffering from large thermal injuries. Protein catabolism precipitating protein malnutrition places patients at greater risk of wound infection and sepsis due to delayed wound healing. Underfeeding, aggressive feeding, feeding routes, timing of initiation of feeding and tight insulin control have all been explored extensively in the quest to understand what nutritional treatment will best attenuate the hypermetabolic response. Despite this it is suggested that the majority of patients with large thermal injuries do not receive adequate nutritional support immediately post injury. Nurses have a pivotal role to play in ensuring that thermal injury patients receive appropriate nutritional support based on the best available evidence.

Feeding During Resuscitation After Burn Injury

Burn injury results in a sustained hypermetabolic state with resulting increased caloric and protein requirements to support the stress and immune responses; augmented protein, fat, and carbohydrate catabolism; oxidative stress; and exudative losses. Along with surgical debridement, nutrition and resuscitation are the foundations of patient management after severe burn injury. Recent literature has demonstrated a clear benefit to early enteral nutrition initiation during the resuscitation period. This review aims to examine recent literature discussing both physiologic impact of burn injury and approaches to feeding during resuscitation after burn injury; including methods of determining nutrition requirements, routes, timing, and monitoring response and the associated benefits and consequences thereof.

Identification and Structure-Activity Relationship of Intestinal Epithelial Barrier Function Protective Collagen Peptides from Alaska Pollock Skin

The effect of collagen peptides (CPs) in intestinal mucosal protection has been approved in both cell and animal models. However, its structure–activity relationship and efficient peptide sequences are unclear, which hinders the in-depth study of its action mechanism and relative nutraceuticals and pharmaceuticals development. In this work, size exclusion chromatography, cation-exchange chromatography, and RP-HPLC were used to separate Alaska pollock skin-derived collagen hydrolysates based on their molecular weight, charge property, and hydrophobicity. The intestinal epithelial barrier function (IEBF) protective effect of separated peptide fractions were evaluated by tumor necrosis factor (TNF)-α-induced Caco-2 cell model. Results indicated that lower molecular weight (500–1000 Da) and higher hydrophilicity of CPs were related to better IEBF protective effect. Two high-efficiency IEBF protective peptide sequences, GPSGPQGSR and GPSGLLGPK with the corresponding molecular weights of 841.41 Da and 824.38 Da, were subsequently identified by UPLC-QToF-MS/MS. Their IEBF protective ability are comparable or even better than the currently used intestinal health supplements glutamine and arginine. The present findings suggested that the hydrophilic CPs, with molecular weight between 500 Da to 1000 Da, should be preferred in IEBF protective peptides preparation. GPSGPQGSR and GPSGLLGPK might have the potential of being IEBF protective ingredients used in intestinal health supplements and drugs.

Early postoperative oral feeding shortens first time of bowel evacuation and prevents long term hospital stay in patients undergoing elective small intestine anastomosis

AIM

This study was conducted to compare outcome of early oral feeding (EOF) versus traditional oral feeding (TOF) in patients undergoing elective small intestine anastomosis.

BACKGROUND

Appropriate nutritional support after major surgeries is a real medical concern. As traditional surgical techniques have been replaced by novel methods, postoperative care should be revised as well. Early postoperative oral feeding was studied in trauma and burn. However, there are few trials among patients after major surgeries.

METHODS

This randomized single-blinded controlled trial was performed on 108 patients who had small intestine anastomosis at Imam Hossein Medical Centre in 2012. The patients were randomly assigned to schedule EOF (with starting oral feeding on the first day after surgery and complete return of the Gag reflex) or TOF (with delaying oral feeding till first passage of flatus and bowel movement). We compared overall prevalence of postoperative complication, length of hospital stay and outcome of surgery in two groups.

RESULTS

The time of the first passage of stool was shorter in EOF group than in TOF group (3.2 ± 0.59 days versus 3.6 ± 0.66 days (p= 0.006). The mean length of hospital stay in EOF group was also shorter than in TOF group (3.8 ± 1.06 days versus 6.3 ± 1.0 days, p= 0.001). The length of hospital stay shorter than 4 days was found in 75.9% of patients in EOF group and 11.1% of those patients in TOF group (p < 0.001).

CONCLUSION

The use of EOF in patients undergoing small intestine anastomosis can shorten time of the first passage of stool as well as reduce length of hospital stay.

New technologies in global burn care - a review of recent advances

There have been truly incredible strides in the standard of burn care. The mortality from burn injuries has more than halved since the 1950s, making it hugely unique among major diseases of the developed world. There can be no doubt technology and technological advances have driven this process, dramatically improved every aspect of burn care, from the intensive care management, the surgical management, management of the healing wound to the post burn sequelae, specifically scar management. This review aims to identify key technological advances in burns, in both the developed and developing world, and evaluate their influence in the continued strategy to improve the standards of global burn care.

Effects of early enteral nutrition supplemented with collagen peptides on post-burn inflammatory responses in a mouse model

The effect of early enteral nutrition (EN) supplemented with Alaska pollock skin-derived collagen peptides (CPs) on post-burn inflammatory responses was investigated in a mouse model. Male blab/c mice were randomly assigned to four groups: a sham burn (SB) group, a control group (burn + EN + glycine, BE), a positive control group (burn + EN + glutamine, BEG) and a treatment group (burn + EN + CPs, BEC). Burn-induced increases of serum endotoxin level, and systemic and intestinal concentration of TNF-α and IL-6 were attenuated in BEG and BEC at post-burn day (PBD) 1, 3 and 7 (p < 0.05 vs. BE). Notably, BEC revealed a prominent decrease of the serum endotoxin level, TNF-α and IL-6 as compared to BEG at PBD 7 (p < 0.05). Furthermore, EN supplemented with CPs diminished the phosphorylation of intestinal NF-κB p65 and simultaneously down-regulated the mRNA expression of TNF-α and IL-6 in small intestine (p < 0.05 vs. BE). Also, it demonstrated a comparable effect with glutamine in ameliorating post-burn inflammatory responses in mice with burns. Therefore, CPs could be considered as a potential immunonutrient supplement in EN to improve post-burn outcomes in burn patients.

Determination of lymphocytes surface markers in patients with thermal burns and the influence of burn size on mononuclear cell subsets

Background: Thermal burn injuries impair the host defence system. Hence, in the present study, we aimed at investigating the changes in the number and phenotype of peripheral blood lymphocyte populations (T, B, and natural killer cells) and their subpopulations in patients with thermal burns and determining the relationships with different sizes of total body surface area (TBSA). Methods: Blood samples from 67 patients, admitted to Motahary Burn Center in Tehran, with burns from 30% to more than 70% TBSA were collected on Days 3 and 7 postburn. Lymphocytes and their subpopulations were identified by monoclonal antibodies. The cells were analyzed using flow cytometry. The results were compared with healthy controls. Results: In this study, 3 and 7 days after burn injury, the percentages of CD3+, CD4+ and CD8+ lymphocyte significantly decreased, CD4+/CD8+ ratios were below the normal range, and CD19+ (B cells) significantly increased. No significant difference was obtained in the mean percentage of CD16+ (NK cells) between Days 3 and 7 postburn. Patients with burns of 30% TBSA or greater (>70%) had a significant reduction in CD3+, CD4+ and CD8+ ( T cells) numbers up to 7 days compared with 3 days after burn injury. Patients with 30% to >70 % TBSA burn failed to show any significant changes in CD4+/CD8+ ratio as well as CD16+ (NK cells) 3 to 7 days after burn. In patients with burns more than 30% to>70% TBSA, CD19+ (B cells) number changes were found to be complicated after 3 and 7 days. Conclusion: The results of this study suggest that alterations of immune cell surface markers and TBSA% can reflect postburn lymphocyte activation.

Effect of parenteral glutamine supplementation combined with enteral nutrition on Hsp90 expression and lymphoid organ apoptosis in severely burned rats

OBJECTIVE

The aim of this study is to investigate the effects of parenteral glutamine(GLN) supplementation combined with enteral nutrition (EN) on heat shock protein 90(Hsp90) expression, apoptosis of lymphoid organs and circulating lymphocytes, immunological function and survival in severely burned rats.

METHODS

Male SD rats were randomly assigned into 4 groups: a sham burn+EN+GLN-free amino acid (AA) group (n=10), a sham burn+EN+GLN group (n=10), a burn+EN+AA group (n=10), and a burn +EN +GLN group (n=10). Two hours after a 30% total body surface area (TBSA), full-thickness scald burn injury on the back was made, the burned rats in two experimental groups (the burn+EN+AA group and the burn+EN +GLN group) were fed with a conventional enteral nutrition solution by oral gavage for 7 days. Simultaneously, the rats in the burn+EN+GLN group were given 0.35g GLN/kg body weight/day once via a tail vein injection for 7 days, whereas those in the burn+EN+AA group were administered isocaloric/isonitrogenous GLN-free amino acid solution (Tyrosine) for comparison. The rats in two sham burn control groups (the sham burn+EN+AA group and the sham burn+EN +GLN group) were treated in the same procedure as above, except for burn injury. All rats in each of the four groups were given 175kcal/kg body wt/day. There was isonitrogenous, isovolumic and isocaloric intake among four groups. At the end of the 7th day after nutritional programme were finished, all rats were anesthetized and samples were collected for further analysis. Serum immunoglobulin quantification was conducted by ELISA. Circulating lymphocyte numbers were counted by Coulter LH-750 Analyzer. The percentages and apoptotic ratio of CD4 and CD8T lymphocytes in circulation were determined by flow cytometry (FCM). The neutrophil phagocytosis index (NPI) was examined. The GLN concentrations in plasma, thymus, spleen and skeletal muscle were measured by high performance liquid chromatography (HPLC). The organ index evaluation and TUNEL analysis of thymus and spleen were carried out. The expression of Hsp90 in thymus and spleen was analyzed by western blotting. Moreover, the survival in burned rats was observed.

RESULTS

The results revealed that parenteral GLN supplementation combined with EN significantly increased the GLN concentrations of plasma and tissues, the serum immunoglobulin content, the circulating lymphocyte number, the CD4/CD8 ratio, the indexes of thymus and spleen, NPI and survival as compared with the burn+EN+AA group (p<0.05). The expression of Hsp90 in thymus and spleen in the burn+EN+GLN group was significantly up-regulated as compared with the burn+EN+AA group (p<0.05). The apoptosis in circulating CD4 and CD8 lymphocytes, thymus and spleen in the burn+EN+GLN group was significantly decreased as compared with the burn+EN+AA group (p<0.05).

CONCLUSION

The results of this study show that parenteral GLN supplementation combined with EN may increase the GLN concentrations of plasma and tissues, up-regulate the expression of Hsp90, attenuate apoptosis in lymphoid organ and circulating lymphocyte, enhance the immunological function and improve survival in severely burned rats. Clinically, therapeutic efforts at the modulation of the immune dysfunction may contribute to a favorable outcome in severely burned patients.