Cutaneous copper and zinc losses in burns

Nutritional and metabolic characteristics of critically ill patients admitted for severe toxidermia

INTRODUCTION

Drug-induced toxidermia is an idiosyncratic adverse skin reaction that may become life-threatening in a small portion of patients, requiring intensive care unit (ICU) admission. The treatment recommendations are extrapolated from those of major burns, while prospective data remain sparse. The objective was to observe the application of these recommendations in patients treated in a burn ICU.

METHOD

Retrospective cohort study including patients requiring ICU between 2006 and 2020 in a tertiary university hospital.

INCLUSION CRITERIA

Age >18 years. Patients were categorized as Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis (SJS/TEN), or other toxidermia.

VARIABLES

severity scores, body surface area (BSA) involvement, nutritional and metabolic variables, trace element status, outcome variables. Descriptive statistics: median [IQR].

RESULTS

Altogether 35 patients were included (27 SJS/TEN and 8 "other"), aged 58 [48; 69] years. Skin involvement was 45% [30; 60] of body surface, 17 patients required mechanical ventilation, and length of ICU stay was 16 [6.5; 26] days. Hospital mortality was 23%. Fluid resuscitation requirements were moderate, despite intense inflammation (admission CRP (144 [89; 218] mg/L). The first 2 weeks' energy and protein intakes were below recommendations (p < 0.0001), lowest with oral feeding. Indirect calorimetry showed high energy expenditure in 11 patients (30.4 [23.9; 35.5] kcal/kg) resulting in negative energy balances (mean -245 kcal/day). Copper and zinc levels were below reference range during the first week, the low copper values being a novel finding.

CONCLUSION

Trace elements should be monitored. The cohort was underfed with intakes lower than our ICU protocols, partly explained by short intubation times, and mucocutaneous involvement complicating the management and placement of feeding tubes. Oral feeding was least efficient and may become an indication for supplemental parenteral nutrition in the absence of an enteral feeding tube.

CLINICALTRIALS

gov Identifier: NCT05320653.

Copper deficiency, a rare but correctable cause of pancytopenia: a review of literature

INTRODUCTION

Copper is increasingly being recognized as a vital mineral required by both animals and humans. It plays a vital role in many metabolic processes such as cellular respiration, iron oxidation, and hemoglobin synthesis. Copper deficiency, which can be hereditary or acquired, can lead to a wide spectrum of disease processes such as ringed sideroblastic anemia, myelodysplasia, and pancytopenia. Timely identification and management of copper deficiency is necessary to prevent irreversible complications.

AREAS COVERED

Our study focuses on prevalence, etiology, pathophysiology, complications, and treatment of copper deficiency.

EXPERT OPINION

Copper deficiency is frequently underrecognized as the cause of anemia, neutropenia, and bone marrow dysplasia. As it is potentially treatable, it should always be kept in the differentials when patients present with neurological and hematological abnormalities.

The Extent of Burn Injury Significantly Affects Serum Micro- and Macroelement Concentrations in Patients on the First Day of Hospitalisation

Burns exceeding 30% of total body surface area (TBSA) result in considerable hypovolemia coupled with the formation and release of inflammatory mediators, leading to subsequent systemic effects known as burn shock. Because of plasma exudation and the associated losses of large quantities of minerals, severe burns can lead to nutritional deficiencies and consequently disrupt homeostasis and metabolism of the entire body. The study group comprised 62 patients, who were divided into 3 groups according to the severity of burns. Serum samples were tested for concentrations of Ca, Mg, Mn, P, K, Zn, Cu, Fe, Se, Na, Cr, Ni, and Al. The mineral concentrations in serum of patients with burn injuries differ significantly from reference values, but this is not affected by the extent of the body burn. There are statistically significant decreases in serum concentrations of elements important for antioxidant protection (Zn, Cu, Se), and significant increases in the concentrations of toxic elements (Al and Ni), which may aggravate the effects associated with the state of burn shock. The Spearman rank correlation analysis did not reveal any statistically significant relationships between the serum concentrations of Mn, Ni, Al, K, Na, P, Mg, Zn, Se, Cr and the affected body surface area and severity of the burn—the values were at the lower end of the reference range. The obtained results indicate that proper nutrition, including elements replenishment, is extremely important in the recovery process of burn patients and time to nutrition is an important factor affecting patient survival after severe burn.

Higher baseline copper levels are associated with worse outcome in burn patients with overweight and obesity

INTRODUCTION

We examined the interactive effects of copper (Cu) and overweight (overweight) and obesity on outcomes of burn patients. We posited that higher baseline Cu among burn patients with overweight or obesity will be associated with poor clinical outcomes vs. patients with a normal weight.

METHODS

A retrospective review was conducted on patients with ≥20% total burn surface area (TBSA) with an initial measurement of Cu. Patients were grouped by body mass index (BMI). The interactions between baseline Cu and BMI groups on multiple burn patient outcomes were examined in a series of multiple regression models.

RESULTS

One-hundred-and-sixty patients met eligibility (age 43.9 ± 17.5, males 86.3%, normal weight:overweight:obesity = 53:38:69). BMI groups did not differ significantly on demographics, burn severity, or baseline biochemistry. Normal weight patients with higher baseline Cu had shorter ICU stay (ICUS), shorter length of stay (LOS), and had fewer operations (Ps < 0.05). In contrast, overweight and obese patients with higher baseline Cu had longer ICU stay (p = 0.001 and p = 0.034), LOS (p = 0.005 and p = 0.066), and increased operations (p = 0.001 and p = 0.067).

CONCLUSIONS

Higher baseline Cu seems associated with adverse outcomes in overweight and obese burn patients. Further research is needed to confirm this association and explore the direction of causality.

Hyperregenerative macrocytic anaemia: the role of copper and zinc

In a patient with a history of bariatric surgery, severe copper deficiency presenting with macrocytic hyperregenerative anaemia was diagnosed. Besides the impaired intestinal absorption due to a short bowel syndrome, the enteral zinc supplementation competitively decreased the intestinal copper uptake. Once the zinc supplementation was stopped, enteral copper replacement ensued and normalised haemoglobin levels with decreasing median corpuscular volume were observed during follow-up visits.

Bioelements in the treatment of burn injuries - The complex review of metabolism and supplementation (copper, selenium, zinc, iron, manganese, chromium and magnesium)

Appropriate nutrition is a key component of burn treatment and should be regarded as an integral part of the therapeutic process in burn patients. A nutritional intervention plan should not only allow for adequate quantities of energy and protein but also carefully consider the supply of macro- and micronutrients. As a result of the severe inflammatory response, oxidative stress, and hypermetabolic state, accompanied by often extensive exudation in burn patients, there is a considerable loss of macro- and micronutrients, including essential trace elements. This leads to certain complications, involving e.g. more frequent infections and impaired wound healing. Our current body of knowledge is still insufficient, and the studies carried out to date focus for the most part on the imbalances in trace elements, such as copper (Cu), selenium (Se), and zinc (Zn). Nevertheless, there are many other trace elements involved in immune functions, regulating gene expression or antioxidant defense, and many of those have not been properly investigated in a clinical setting. Due to the insufficient amount of unambiguous literature data and relatively few, often dated, studies carried out with small patient groups, further evaluation of macro- and microelements in burn patients seems indispensable, e.g. to bring up to date local nutritional protocols.

Nutrition and Micronutrient Therapy in Critical Illness Should Be Individualized

Critically ill (intensive care unit [ICU]) patients are characterized by organ failure, intense inflammatory response, insulin resistance, and altered metabolic response. The sicker the patient, the higher the threat to nutrition and micronutrient status. In addition, many patients start the ICU stay with an altered nutrition status, which requires assessment upon admission. Nutrition needs vary among patients as well as during hospitalization, as the metabolic response changes over time. Shock and acute organ failure result in a metabolic shift toward intense catabolism: endogenous glucose production aiming at ensuring the basal adenosine triphosphate production starts immediately and occurs at the expense of the lean body mass using amino acids for neoglucogenesis. Later, the stabilization and recovery phases are characterized by higher energy and substrate needs. Indirect calorimetry is the only tool enabling determination of the metabolic level. When and how should feeding be started? Recent research shows that the route does not matter much, with equipoise between enteral and parenteral nutrition (PN) as long as overfeeding is avoided. As micronutrients are an integral part of metabolism and antioxidant defenses, their delivery must be ensured: whereas needs are well defined for healthy individuals, needs for illness remain poorly defined. PN that contains only macrosubstrates requires the daily prescription of multimicronutrient complements to qualify as total PN. Achievement of goals requires minimal monitoring, consisting of the daily verification of energy and protein goal delivery achievement and daily follow-up determining blood glucose and phosphate levels and insulin requirements.

Parenteral Provision of Micronutrients to Adult Patients: An Expert Consensus Paper

BACKGROUND

Micronutrients, an umbrella term used to collectively describe vitamins and trace elements, are essential components of nutrition. Those requiring alternative forms of nutrition support are dependent on the prescribed nutrition regimen for their micronutrient provision. The purpose of this paper is to assist clinicians to bridge the gap between the available guidelines' recommendations and their practical application in the provision of micronutrients via the parenteral route to adult patients.

METHODS

Based on the available evidenced-based literature and existing guidelines, a panel of multidisciplinary healthcare professionals with significant experience in the provision of parenteral nutrition (PN) and intravenous micronutrients developed this international consensus paper.

RESULTS

The paper addresses 14 clinically relevant questions regarding the importance and use of micronutrients in various clinical conditions. Practical orientation on how micronutrients should be prescribed, administered, and monitored is provided.

CONCLUSION

Micronutrients are a critical component to nutrition provision and PN provided without them pose a considerable risk to nutrition status. Obstacles to their daily provision-including voluntary omission, partial provision, and supply issues-must be overcome to allow safe and responsible nutrition practice.

A 'metabolic bundle' including Oxandrolone in optimising the metabolic status of severely burn injured patients: a retrospective analysis of the first 50 patients

Objective: Severe burn injuries are associated with a rapid escalating hypermetabolic state and catabolism of muscle mass. To ameliorate this process a standardized approach using pharmacological and non-pharmacological interventions was implemented within a single burns center. Whilst individual components of this standardized package are well documented in the literature, their collective or bundled effect has not as yet been assessed. The aim of this study was to evaluate the efficacy of this standardized bundle of metabolic modulators and assess the safety of including the anabolic steroid oxandrolone within it. Methods: This retrospective observational study constituted all patients in whom the metabolic bundle including oxandrolone therapy was applied. The other elements of the metabolic bundle consisted of early surgical burn excision within seven days to completion, early active mobilization, increased ambient room temperature, expediated carbohydrate and protein rich enteral feeding with glutamine and trace element supplements (such as copper and zinc). Finally, administration of propranolol as a non-selective beta-blocker. Data collection was through review of the patient data management system focusing on the outcome criteria and hepatic blood values. Results: The study looked at fifty consecutive patients meeting the inclusion criteria. Median patient age and burned total body surface area (TBSA) were 62 years [51.75; 73] and 33.75% [24.75; 51] respectively with an abbreviated burn severity index (ABSI) of 10 [9; 10.25]. Definitive surgical burn wound excision was completed in 44 patients [88%] within 7 days. 39 patients (78%) received propranolol over a therapeutic period of 29 days [19; 44]. Glutamine was supplemented in 45 patients (90%), while zinc and copper were applied to 42 (84%) and 31 (62%) respectively. Significant low zinc values were noted at therapeutic onset (6.5 mmol/l [4.7; 7.9]) requiring sustained substitution over 37.5 days [22; 46.75]). In respect of the inclusion criteria, all patients received oxandrolone at 20 mg/day [20; 20]. This was commenced on day 6.5 [4; 14] post burn injury and continued over 26 days [19; 31]. Despite a transitory elevation of hepatic enzyme values (ALT, GGT), these were only clinically relevant (>10 µmol/l*S) in 2.4% and 4.6% of all measurements respectively. None were sufficiently of concern to merit cessation of treatment. Conclusion: The application of a standardised bundle of metabolic treatment options of severe burns injured patients is reliable, repeatable and safe. Potential concerns of oxandrolone treatment regarding hepatic compromise remain unfounded.

Copper Deficiency: Causes, Manifestations, and Treatment

BACKGROUND

The metabolism of the essential trace element copper remains incompletely understood and, until recently, nearly ignored in acute medicine. Menkes disease was for long the only known copper deficiency condition, but several case reports and investigations conducted over the last 2 decades have shown that deficiency is more frequent than previously suspected, with devastating individual consequences and potential public health consequences. The copper needs in healthy individuals are 0.9 mg/d, which translates to 0.3 mg/d intravenously in parenteral nutrition; the present review aims at gathering actual knowledge.

METHOD AND RESULTS

A review of literature was conducted in PubMed and Cochrane systematic reviews to identify the most recent information about copper deficiency and generate a narrative review. Copper deficiency has hereditary and acquired origins, the latter being the most frequent. Clinical manifestations are nonspecific but affect all organs and systems, particularly the hematologic (anemia) and the neurologic (myeloneuropathy) systems. Deficiency also affects the cardiovascular, cutaneous, and immune systems. Severe copper deficiency due to reduced absorption after bariatric bypass surgery has become frequent.

CONCLUSION

Deficiency is more frequent than previously recognized, probably because of changing nutrition patterns but also because of some treatments that have become very common such as bypass bariatric surgery and, in acute medicine, prolonged continuous renal replacement therapy. The patients may present with severe hematologic and neurologic complications that go untreated because copper deficiency was not considered in the differential diagnosis: These complications often need active intravenous repletion with doses 4-8 times the usual nutrition recommendations.

Trace Elements in Parenteral Nutrition: Considerations for the Prescribing Clinician

Trace elements (TEs) are an essential component of parenteral nutrition (PN). Over the last few decades, there has been increased experience with PN, and with this knowledge more information about the management of trace elements has become available. There is increasing awareness of the effects of deficiencies and toxicities of certain trace elements. Despite this heightened awareness, much is still unknown in terms of trace element monitoring, the accuracy of different assays, and current TE contamination of solutions. The supplementation of TEs is a complex and important part of the PN prescription. Understanding the role of different disease states and the need for reduced or increased doses is essential. Given the heterogeneity of the PN patients, supplementation should be individualized.

Nutrients and Wound Healing: Still Searching for the Magic Bullet

Clinicians in nearly all practice areas are confronted with the challenges associated with delayed and impaired wound healing. Although nutrition plays a critical role in the healing process, controversy exists regarding the optimal nutrition regimen. This article reviews literature related to nutrition interventions that facilitate wound healing. The limitations of the research that forms the scientific basis of many nutrition recommendations are also examined. The limited availability of rigorously performed clinical studies to develop evidence-based guidelines for nutrition support in wound care emphasizes the need for further research and underscores the importance of individualizing the nutrition care plan for each patient.

Antioxidant Micronutrients in Major Trauma and Burns: Evidence and Practice

There has been a growing interest in micronutrients as a result of their essential role in endogenous antioxidant defense mechanisms and immunity. Critically ill burn and trauma patients are characterized by an increased free radical production, which is proportional to the severity of the injury. In addition, they are at high risk of negative trace element balances, which contribute to the imbalance in endogenous antioxidant capacity and the extension of primary lesions. Although selenium, zinc, and vitamin C and E status are altered in all injured patients, patients with major burns are unique for having copper deficiency. In major burns, high-dose ascorbic acid for 24 hours achieves reduction of resuscitation fluid requirements by endothelial antioxidant mechanisms both in animal models and in 1 human trial. Supplementation trials in trauma and burns including selenium and zinc have shown that early provision of micronutrients improves recovery. Vitamin supplementation trials without selenium have not achieved definitive effects. The human studies show that reinforcing antioxidant defenses early in the course of major injury is rational and that substituting the large initial micronutrient losses of selenium and zinc is safe in trauma, as is the addition of copper in burns. The IV route seems the only way to deliver the doses required to obtain a clinical effect.

Topical Negative Pressure on Burns: An Innovative Method for Wound Exudate Collection

Supplemental Digital Content is available in the text.

Burn wound exudate is an important source of information on the wound-healing process and systemic improvement of burn patients. Identification of biomarkers for the prediagnosis of local or systemic complications in patients will have a great impact on adapting personalized procedures in burn treatment. No efficient exudate collection method exists that offers a direct and continuous collection over time. We developed an innovative system based on the negative pressure wound therapy technique to directly collect exudate from burn wounds over several days after burn. This method did not cause any complication or pain for patients, and positive influence on wound healing was seen. Exudate samples were further used in different projects for studying biochemical profile, trace element content, kinetics of bacterial growth, and cell cytotoxicity.

Parenteral trace element provision: recent clinical research and practical conclusions

The aim of this systematic review (PubMed, www.ncbi.nlm.nih.gov/pubmed and Cochrane, www.cochrane.org; last entry 31 December 2014) was to present data from recent clinical studies investigating parenteral trace element provision in adult patients and to draw conclusions for clinical practice. Important physiological functions in human metabolism are known for nine trace elements: selenium, zinc, copper, manganese, chromium, iron, molybdenum, iodine and fluoride. Lack of, or an insufficient supply of, these trace elements in nutrition therapy over a prolonged period is associated with trace element deprivation, which may lead to a deterioration of existing clinical symptoms and/or the development of characteristic malnutrition syndromes. Therefore, all parenteral nutrition prescriptions should include a daily dose of trace elements. To avoid trace element deprivation or imbalances, physiological doses are recommended.

Zinc: physiology, deficiency, and parenteral nutrition

The essential trace element zinc (Zn) has a large number of physiologic roles, in particular being required for growth and functioning of the immune system. Adaptive mechanisms enable the body to maintain normal total body Zn status over a wide range of intakes, but deficiency can occur because of reduced absorption or increased gastrointestinal losses. Deficiency impairs physiologic processes, leading to clinical consequences that include failure to thrive, skin rash, and impaired wound healing. Mild deficiency that is not clinically overt may still cause nonspecific consequences, such as susceptibility to infection and poor growth. The plasma Zn concentration has poor sensitivity and specificity as a test of deficiency. Consequently, diagnosis of deficiency requires a combination of clinical assessment and biochemical tests. Patients receiving parenteral nutrition (PN) are susceptible to Zn deficiency and its consequences. Nutrition support teams should have a strategy for assessing Zn status and optimizing this by appropriate supplementation. Nutrition guidelines recommend generous Zn provision from the start of PN. This review covers the physiology of Zn, the consequences of its deficiency, and the assessment of its status, before discussing its role in PN.

Micronutrients after burn injury: a review

Supplementation of micronutrients after burn injury is common practice in order to fight oxidative stress, support the immune system, and optimize wound healing. Assessing micronutrient status after burn injury is difficult because of hemodilution in the resuscitation phase, redistribution of nutrients from the serum to other organs, and decreases in carrier proteins such as albumin. Although there are many preclinical data, there are limited studies in burn patients. Promising research is being conducted on combinations of micronutrients, especially via the intravenous route.

Sputum containing zinc enhances carbapenem resistance, biofilm formation and virulence of Pseudomonas aeruginosa

Pseudomonas aeruginosa chronic lung infections are the leading cause of mortality in cystic fibrosis patients, a serious problem which is notably due to the numerous P. aeruginosa virulence factors, to its ability to form biofilms and to resist the effects of most antibiotics. Production of virulence factors and biofilm formation by P. aeruginosa is highly coordinated through complex regulatory systems. We recently found that CzcRS, the zinc and cadmium-specific two-component system is not only involved in metal resistance, but also in virulence and carbapenem antibiotic resistance in P. aeruginosa. Interestingly, zinc has been shown to be enriched in the lung secretions of cystic fibrosis patients. In this study, we investigated whether zinc might favor P. aeruginosa pathogenicity using an artificial sputum medium to mimic the cystic fibrosis lung environment. Our results show that zinc supplementation triggers a dual P. aeruginosa response: (i) it exacerbates pathogenicity by a CzcRS two-component system-dependent mechanism and (ii) it stimulates biofilm formation by a CzcRS-independent mechanism. Furthermore, P. aeruginosa cells embedded in these biofilms exhibited increased resistance to carbapenems. We identified a novel Zn-sensitive regulatory circuit controlling the expression of the OprD porin and modifying the carbapenem resistance profile. Altogether our data demonstrated that zinc levels in the sputum of cystic fibrosis patients might aggravate P. aeruginosa infection. Targeting zinc levels in sputum would be a valuable strategy to curb the increasing burden of P. aeruginosa infections in cystic fibrosis patients.

Trace element monitoring in the ICU: quality and economic impact of a change in sampling practice

BACKGROUND & AIMS

Trace elements (TE) are involved in the immune and antioxidant defences which are of particular importance during critical illness. Determining plasma TE levels is costly. The present quality control study aimed at assessing the economic impact of a computer reminded blood sampling versus a risk guided on-demand monitoring of plasma concentrations of selenium, copper, and zinc.

METHODS

Retrospective analysis of 2 cohorts of patients admitted during 6 months periods in 2006 and 2009 to the ICU of a University hospital.

INCLUSION CRITERIA

to receive intravenous micronutrient supplements and/or to have a TE sampling during ICU stay. The TE samplings were triggered by computerized reminder in 2006 versus guided by nutritionists in 2009.

RESULTS

During the 2 periods 636 patients met the inclusion criteria out of 2406 consecutive admissions, representing 29.7% and 24.9% respectively of the periods' admissions. The 2009 patients had higher SAPS2 scores (p = 0.02) and lower BMI compared to 2006 (p = 0.007). The number of laboratory determinations was drastically reduced in 2009, particularly during the first week, despite the higher severity of the cohort, resulting in à 55% cost reduction.

CONCLUSIONS

The monitoring of TE concentrations guided by a nutritionist resulted in a reduction of the sampling frequency, and targeting on the sickest high risk patients, requiring a nutritional prescription adaptation. This control leads to cost reduction compared to an automated sampling prescription.

Heavy metal in the intensive care unit: a review of current literature on trace element supplementation in critically ill patients

Trace elements are essential for many physiologic processes. In recent years, supplementation has been studied for a variety of indications, including glycemic control, wound healing, antioxidant effect, and anemia. Critical illness, especially states such as burns, traumas, and septic shock, is associated with inflammatory and oxidative stress, immune dysfunction, and malnutrition. In these patients, enteral and parenteral nutrition or pharmaceutical supplementation is used to provide essential macronutrients, including trace elements. The purpose of this review is to describe trace element supplementation, including iron, copper, chromium, manganese, selenium, and zinc, and highlight their mechanism, pharmacology, outcome data, and adverse effects.

Enteral nutrition support in burn care: a review of current recommendations as instituted in the Ross Tilley Burn Centre

Failure to adequately address the increased levels of inflammatory mediators, catecholamines and corticosteroids central to the hypermetabolic response post burn injury can lead to catastrophic results. One of the most important perturbations is provision of adequate and early nutrition. The provision of the right balance of macro and micronutrients, along with additional antioxidants is essential to mitigating the hypermetabolic and hypercatabolic state that results following a burn injury. As it is now widely accepted that enteral feeding is best practice for the burn population research has been more closely examining the individual components of enteral nutrition support. Recently fat to carbohydrate ratios, glutamine and antioxidants have made up the balance of this focus. This paper provides a review of the most recent literature examining each of these components and discusses the practices adopted in the Ross Tilley Burn Centre at Sunnybrook Health Sciences Centre.

A.S.P.E.N. position paper: recommendations for changes in commercially available parenteral multivitamin and multi-trace element products

The parenteral multivitamin preparations that are commercially available in the United States (U.S.) meet the requirements for most patients who receive parenteral nutrition (PN). However, a separate parenteral vitamin D preparation (cholecalciferol or ergocalciferol) should be made available for treatment of patients with vitamin D deficiency unresponsive to oral vitamin D supplementation. Carnitine is commercially available and should be routinely added to neonatal PN formulations. Choline should also be routinely added to adult and pediatric PN formulations; however, a commercially available parenteral product needs to be developed. The parenteral multi-trace element (TE) preparations that are commercially available in the U.S. require significant modifications. Single-entity trace element products can be used to meet individual patient needs when the multiple-element products are inappropriate (see Summary/A.S.P.E.N. Recommendations section for details of these proposed modifications).

Military nutrition: maintaining health and rebuilding injured tissue

Food and nutrition are fundamental to military capability. Historical examples demonstrate that a failure to supply adequate nutrition to armies inevitably leads to disaster; however, innovative measures to overcome difficulties in feeding reap benefits, and save lives. In barracks, UK Armed Forces are currently fed according to the relatively new Pay As You Dine policy, which has attracted criticism from some quarters. The recently introduced Multi-Climate Ration has been developed specifically to deal with issues arising from Iraq and the current conflict in Afghanistan. Severely wounded military personnel are likely to lose a significant amount of their muscle mass, in spite of the best medical care. Nutritional support is unable to prevent this, but can ameliorate the effects of the catabolic process. Measuring and quantifying nutritional status during critical illness is difficult. A consensus is beginning to emerge from studies investigating the effects of nutritional interventions on how, what and when to feed patients with critical illness. The Ministry of Defence is currently undertaking research to address specific concerns related to nutrition as well as seeking to promote healthy eating in military personnel.

Effect of sub-deficient zinc status on insulin sensitivity after burn injury in rats

Although zinc status is an important parameter in insulin sensitivity, data concerning its implication in noxious burn-induced insulin resistance are scarce. The present study was designed to evaluate the impact of zinc status before burn on the recovery of injury with focus on plasma insulin and glucose levels. The experiment was performed in male adult Wistar rats fed from weaning with a zinc normal diet (80 ppm) or a depleted zinc diet (10 ppm) for 8 weeks and burned to third degree on 20% of their total body surface area. Blood and tissue samples were collected 3, 6, and 24 h after injury in order to study biochemical parameters and the glucose/insulin response in relation with the zinc status. After burn, zinc-depleted rats presented an exacerbated decrease in plasma zinc level. In addition, the burn-induced insulin resistance, leading to protein catabolism, was emphasized, with higher plasma insulin, glucose, and leptin levels in zinc-deficient animals versus normal-fed rats. Our experimental results underlined the interest to early control the zinc status in order to limit the deleterious effects of oxidative stress and insulin resistance in burned patients.

Burn-induced oxidative stress is altered by a low zinc status: kinetic study in burned rats fed a low zinc diet

As an initial subdeficient status of zinc, considered as an essential antioxidant trace element, is frequent in burned patients, we aim to assess the effects of low zinc dietary intakes on burn-induced oxidative stress, in an animal model. After 8 weeks of conditioning diets containing 80 ppm (control group) or 10 ppm of zinc (depleted group), Wistar rats were 20% TBSA burned and sampled 1-10 days after injury. Kinetic evolutions of zinc status, plasma oxidative stress parameters, and antioxidant enzymes were also studied in blood and organs. The zinc-depleted diet induced, before injury, a significant decrease in zinc bone level and the increase of oxidative stress markers without stimulation of antioxidant enzyme activity. After burn, more markedly in zinc depleted animals than in controls, zinc levels decreased in plasma and bone, while increasing in liver. The decrease of thiol groups and GSH/GSSG ratio and the depression of GPx activity in liver are also moderately emphasized. Nevertheless, depleted zinc status could not be considered as determining for oxidative damages after burn injury. Further investigations must also be done to enlighten the mechanism of beneficial effects of zinc supplementation reported in burned patients.

Emergency treatment of severely burned pediatric patients: current therapeutic strategies

Burn trauma represents a devastating injury and remains as one of the leading causes of mortality and morbidity in children. Effective prevention strategies, advances in therapeutic techniques, based on an improved understanding of fluid resuscitation, appropriate infection control and improved treatment of inhalation injury, enhanced wound coverage, better nutritional regimens, advanced support of the hypermetabolic response to injury and improved glucose control, have significantly improved the clinical outcome of this unique patient population over the past years. This article aims to outline the current and emerging therapeutic strategies for the treatment of severely burned pediatric patients in the emergency department or initial phase of the intensive care unit.

Monitoring the clinical introduction of a glutamine and antioxidant solution in critically ill trauma and burn patients

OBJECTIVE

Enteral glutamine supplementation and antioxidants have been shown to be beneficial in some categories of critically ill patients. This study investigated the impact on organ function and clinical outcome of an enteral solution enriched with glutamine and antioxidant micronutrients in patients with trauma and with burns.

METHODS

This was a prospective study of a historical control group including critically ill, burned and major trauma patients (n = 86, 40 patients with burns and 46 with trauma, 43 in each group) on admission to an intensive care unit in a university hospital (matching for severity, age, and sex). The intervention aimed to deliver a 500-mL enteral solution containing 30 g of glutamine per day, selenium, zinc, and vitamin E (Gln-AOX) for a maximum of 10 d, in addition to control treatment consisting of enteral nutrition in all patients and intravenous trace elements in all burn patients.

RESULTS

Patients were comparable at baseline, except for more inhalation injuries in the burn-Gln-AOX group (P = 0.10) and greater neurologic impairment in the trauma-Gln-AOX group (P = 0.022). Intestinal tolerance was good. The full 500-mL dose was rarely delivered, resulting in a low mean glutamine daily dose (22 g for burn patients and 16 g for trauma patients). In burn patients intravenous trace element delivery was superior to the enteral dose. The evolution of the Sequential Organ Failure Assessment score and other outcome variables did not differ significantly between groups. C-reactive protein decreased faster in the Gln-AOX group.

CONCLUSION

The Gln-AOX supplement was well tolerated in critically ill, injured patients, but did not improve outcome significantly. The delivery of glutamine below the 0.5-g/kg recommended dose in association with high intravenous trace element substitution doses in burn patients are likely to have blunted the impact by not reaching an efficient treatment dose. Further trials testing higher doses of Gln are required.

Trace element supplementation after major burns modulates antioxidant status and clinical course by way of increased tissue trace element concentrations

BACKGROUND

After major burns, patients can develop nutritional deficiencies including trace element (TE) deficiencies. Various complications, such as infections and delayed wound healing, influence the clinical course of such patients.

OBJECTIVES

We aimed to investigate the effects of large, intravenous doses of TE supplements on circulating and cutaneous TE tissue concentrations, on antioxidant status, and on clinical outcome after major burns.

DESIGN

This was a prospective, randomized, placebo-controlled trial in 21 patients aged 35 +/- 11 y (x +/- SD) with burns on 45 +/- 21% of their body surface area. Intravenous copper, selenium, and zinc (TE group) or vehicle (V group) was given with a saline solution for 14-21 d. Blood and urine samples were collected until day 20, and skin biopsy specimens were collected on days 3, 10, and 20.

RESULTS

The age of the patients and the severity of their burns did not differ significantly between the groups. Plasma TE concentrations were significantly higher in the TE group. In burned areas, skin contents of both selenium (P=0.05) and zinc (P=0.04) increased significantly by day 20. Plasma and tissue antioxidant status was improved by supplementation. The number of infections in the first 30 d was significantly lower in the TE group (P=0.015), with a median number of 2 versus 4 infections per patient in the TE and V groups, respectively, as a result of a reduction in pulmonary infections (P=0.03). Wound healing was improved in the TE group, with lower requirements for regrafting (P=0.02).

CONCLUSIONS

TE supplementation was associated with higher circulating plasma and skin tissue contents of selenium and zinc and improved antioxidant status. These changes were associated with improved clinical outcome, including fewer pulmonary infections and better wound healing.

Trace element supplementation after major burns increases burned skin trace element concentrations and modulates local protein metabolism but not whole-body substrate metabolism

BACKGROUND

After major burns, patients exhibit an intense catabolism, and the wounds require surgery and grafting for closure. Complications, such as weight loss and delayed wound healing, are worsened by trace element (TE) deficiencies.

OBJECTIVE

We aimed to assess the effects of TE supplements on systemic substrate turnover and local protein metabolism during wound healing after major burns.

DESIGN

This was a prospective, randomized, placebo-controlled trial in 21 patients aged 35 +/- 11 y with burns on 45 +/- 16% of their body surface area; 12 had skin biopsies performed on days 3, 10, and 20, and 10 patients underwent a stable-isotope investigation on day 10. Intravenous copper, selenium, and zinc (TE group) or vehicle (V group) was given with a saline solution for 14-21 d. On day 10, [(13)C]phenylalanine (600-microg/kg bolus followed by 12 microg x kg(-1) x min(-1)) plus 6-[(2)H(2)]glucose and [(2)H(5)]glycerol were infused for 6 h to determine skin protein turnover. Biopsies were performed 1 and 6 h after the start of infusion to determine [(13)C]phenylalanine enrichment.

RESULTS

The patients' mean age and burn severity did not differ significantly between the groups nor between the skin investigations subgroups. Plasma TE concentrations were significantly higher in the TE group. In the burned areas, the skin contents of selenium (P=0.02) and zinc (P=0.03) increased by day 20. The supernatant-to-plasma (13)C enrichment ratio in burned skin was 0.363 +/- 0.094 (TE group) and 0.286 +/- 0.130 (V group) after 1 h (NS) and 0.592 +/- 0.153 (TE group) and 0.262 +/- 0.171 (V group) after 6 h, which reflected lower catabolism in the TE group (P=0.03). No significant differences in whole-body substrate turnover were found between the groups.

CONCLUSION

TE supplementation was associated with an increased skin tissue content of selenium and zinc and with a reduction in skin protein catabolism.