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

Effects of maternal mild zinc deficiency and different ways of zinc supplementation for offspring on learning and memory

Background

The effect of different ways of zinc supplementation on spatial learning and memory remains unclear.

Objectives

This study aims to assess the effectiveness of two ways of zinc supplementation – oral use and intravenous transfusion – in zinc-deficient offspring rats on learning and memory.

Design

Rats were randomly divided into six groups on the first day of pregnancy (n=12): control (CO), pair fed (PF), zinc deprived (ZD), oral zinc supplementation (OZS), injection zinc supplementation (IZS), and injection control. The offspring's spatial learning and memory were tested at postnatal day 35 using Morris water maze (MWM). Maternal rats’ serum zinc was measured at postnatal day 21, while pups’ serum zinc was measured at postnatal day 35.

Results

Compared with the CO and PF groups, pups in ZD group spent more time finding the latent platform and swam longer distances (p<0.05). Compared with ZD groups, pups in OZS group significantly decreased the time used for finding the platform and the swimming distance (p<0.05) and were similar to that of CO and PF groups (p>0.05). However, compared with ZD groups, pups in IZS did not show any improvement in the indexes of MWM (p>0.05) although their zinc serum concentration increased significantly (p<0.05).

Conclusions

These results indicate that mild zinc deficiency during pregnancy and lactation leads to the impairment of learning and memory function in offspring, and that OZS, instead of intravenous transfusion zinc supplementation, can recover the impairment of spatial learning and memory function.

Determination of kinetic parameters of Phlomis bovei de Noé using thermogravimetric analysis

This paper reports the pyrolysis study of Phlomis bovei biomass by thermogravimetric experiments in order to determine the thermal degradation behavior and kinetic parameters. The weight losses were found to occur in three stages. In the DTG thermograms, an increase of the heating rate tended to delay thermal degradation processes towards higher temperatures. The average values of activation energy and pre-exponential factor calculated from Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Kissinger methods are 134.83, 134.06, 223.31kJ/mol and 4.1610(13), 1.1810(10), 2.8110(11)/s, respectively. The three-pseudo-component method shows that the activation energy increases with increasing the heating rate for hemicellulose and cellulose while the activation energy of the lignin decreased with an increase of the heating rate. Predicted results and experimental data exhibit similar tendencies and the three pseudo-components model with n different from unity 1 is recommended as the most suitable for prediction of kinetic behavior of Phlomis bovei de Noé.

Nutrition and anabolic pharmacotherapies in the care of burn patients

Thermal injury is a devastating injury that results in a number of pathological alterations in almost every system in the body. Hypermetabolism, muscle wasting, depressed immunity, and impaired wound healing are all clinical features of burns. Failure to address each of these specific pathological alterations can lead to increased mortality. Nutrition supplementation has been recommended as a therapeutic tool to help attenuate the hypermetabolism and devastating catabolism evident following burn. Despite the wide consensus on the need of nutrition supplementation in burn patients, controversy exists with regard to the type and amount of nutrition recommended. Nutrition alone is also not enough in these patients to halt and reverse some of the damage done by the catabolic pathways activated following severe burn injury. This has led to the use of anabolic pharmacologic agents in conjunction with nutrition to help improve patient outcome following burn injury. In this review, we examine the relevant literature on nutrition after burn injury and its contribution to the attenuation of the postburn hypermetabolic response, impaired wound healing, and suppressed immunological responses. We also review the commonly used anabolic agents clinically in the care of burn patients. Finally, we provide nutrition and pharmacological recommendations gained from prospective trials, retrospective analyses, and expert opinions based on our practice at the Ross Tilley Burn Center in Toronto, Canada.

The effect of parenteral selenium on outcomes of mechanically ventilated patients following sepsis: a prospective randomized clinical trial

Background

Sepsis and septic shock is characterized by oxidative stress that mainly promotes systemic inflammation and organ failure due to excessive free radical production and depletion of antioxidant defenses. Therefore, we investigated the effect of selenium administration on antioxidant status, levels of cytokines and clinical outcomes.

Methodology

This study was a prospective randomized control trial (RCT) whereby patients received selenium as sodium selenite (2 mg IV bolus followed by 1.5 mg continuous infusion for 14 days) plus standard therapy. The control group received standard therapy without selenium. The primary endpoint was 28-day mortality. The changes in the mean levels of glutathione peroxidase (GPX) activity, IL-6, IL-8 and IL-10, the incidence of ventilator-associated pneumonia (VAP) and other secondary endpoints were also recorded. VAP was broken down into early VAP and late VAP to see the clinical significance of each. We also recorded any adverse outcomes from selenium infusion.

Results

Over 24-month period, 54 patients were recruited and randomized and an intention to treat (ITT) principle was applied (selenium, n = 29; control, n = 25) in the final analysis. There was no statistically significant difference between the two groups in 28-day mortality although it was lower in the selenium group compared with the control group: 9 (31 %) in the selenium versus 10 (40 %) in the control groups (p = 0.49). At day 0, GPX activity was 0.185 ± 0.3 versus 0.19 ± 0.3 U/mL (p = 0.9), day 3, GPX activity was 0.52 ± 0.5 versus 0.17 ± 0.2 U/mL (p = 0.02), at day 7 it was 0.55 ± 0.5 versus 0.24 ± 0.3 U/mL (p = 0.032), at day 10 it was 0.62 ± 0.7 versus 0.33 ± 0.4 U/mL (p = 0.048) and at day 14 it was 1.1 ± 1 versus 0.89 ± 1 U/mL (p = 0.70) for the selenium versus control groups, respectively. However, there were no significant differences between the mean plasma levels of all the three inflammatory cytokines at any point in time between the two groups. There was a significant reduction in occurrence of VAP in the selenium group compared with the control group (55.2 versus 84 %, p = 0.023), respectively.

Conclusion

High-dose selenium administration within the time frame of early goal-directed therapy was not resulted in reduction of 28-day mortality, but increased the activity of glutathione peroxidase with no effect on the levels of inflammatory cytokines at any point in time in mechanically ventilated septic patients. However, selenium supplementation in mechanically ventilated patients following sepsis was associated with reduced occurrence of VAP.

Trial registration: IRCT201212082887N4 at WHO Clinical Trial Registry, August 29, 2014

Selenium supplementation for critically ill adults

BACKGROUND

Selenium is a trace mineral essential to health and has an important role in immunity, defence against tissue damage and thyroid function. Improving selenium status could help protect against overwhelming tissue damage and infection in critically ill adults. This Cochrane review was originally published in 2004 updated in 2007 and again 2015.

OBJECTIVES

The primary objective was to examine the effect of nutrition supplemented with selenium or ebselen on mortality in critically ill patients.The secondary objective was to examine the relationship between selenium or ebselen supplementation and number of infections, duration of mechanical ventilation, length of intensive care unit stay and length of hospital stay.

SEARCH METHODS

In this update, we searched the current issue of the Cochrane Central Register of Controlled Trials, the Cochrane Library (2014, Issue 5); MEDLINE (Ovid SP, to May 20, 2014), EMBASE (Ovid SP, to May 20, 2014), CAB, BIOSIS and CINAHL. We handsearched the reference lists of the newest reviews and cross-checked with our search in MEDLINE. We contacted the main authors of included studies to request any missed, unreported or ongoing studies. The latest search was performed up to 21 May 2014. The search is now from inception until 21 May 2014.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) irrespective of publication status, date of publication, blinding status, outcomes published or language. We contacted the trial investigators and authors in order to retrieve relevant and missing data.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and we resolved any disagreements by discussion. Our primary outcome measure was all-cause mortality. We performed several subgroup and sensitivity analyses to assess the effects of selenium in critically ill patients. We presented pooled estimates of the effects of intervention as risk ratios (RRs) with 95% confidence intervals (CIs). We assessed the risk of bias through assessment of trial methodological components and the risk of random error through trial sequential analysis.

MAIN RESULTS

We included six new RCTs in this review update. In total we included 16 RCTs (2084 participants) in this review. Most trials were at high risk of bias. The availability of outcome data was limited and trials involving selenium supplementation were, with the exception of one trial, small regarding sample size. Thus the results must be interpreted with caution.Thirteen trials of intravenous sodium selenite showed a statistically significant reduction in overall mortality (RR 0.82, 95% CI 0.72 to 0.93, 1391 participants, very low quality of evidence). However, the overall point estimate on mortality is primarily influenced by trials of high risk of bias. Meta-analysis of three trials of ebselen had a RR of 0.83 (95% CI 0.52 to 1.34, 693 participants, very low quality of evidence).Nine trials of intravenous sodium selenite were analysed for 28 days mortality with no statistically significant difference (RR 0.84, 95% CI 0.69 to 1.02, 1180 participants, very low quality of evidence) while three trials were analysed for 90 days mortality with similar findings (RR 0.96, 95% Cl 0.78 to 1.18, 614 participants, very low quality of evidence).Two trials of ebselen were analysed for 90 days mortality and were not found to yield any benefit (RR 0.72, 95% Cl 0.42 to 1.22, 588 participants, very low quality of evidence).For mortality among intensive care patients selenium supplementation failed to indicate any statistically significant advantage (RR 0.88, 95% CI 0.77 to 1.01, nine trials, 1168 participants, very low quality of evidence).Six trials of intravenous sodium selenite found no statistically significant difference for participants developing infection (RR 0.96, 95% CI 0.75 to 1.23, 934 patients, very low quality of evidence). Similarly, three trials of ebselen provided data for participants developing infections (pyrexia, respiratory infections or meningitis) with no obvious benefit (RR 0.60, 95% CI 0.36 to 1.02, 685 participants, very low quality of evidence).Our analyses showed no effect of selenium or ebselen on adverse events (Selenium: RR 1.03, 95% Cl 0.85 to 1.24; six trials, 925 participants ; Ebselen: RR 1.16, 95% CI 0.40 to 3.36; two trials, 588 participants, very low quality of evidence).No clear evidence emerged in favour of selenium supplementation for outcomes such as number of days on a ventilator (mean difference (MD) -0.86, 95% CI -4.39 to 2.67, four trials, 191 participants, very low quality of evidence), length of intensive care unit stay (MD 0.54, 95% CI -2.27 to 3.34, seven trials, 934 participants, very low quality of evidence) or length of hospital stay (MD -3.33, 95% Cl -5.22 to -1.44, five trials, 693 participants, very low quality of evidence).The quality of trial methodology was low. Due to high risk of bias in the included trials, results must be interpreted with caution.

AUTHORS' CONCLUSIONS

Despite publication of a number of trials, the current evidence to recommend supplementation of critically ill patients with selenium or ebselen remains disputed. Trials are required which overcome the methodological inadequacies of the reviewed studies, particularly in relation to sample size, design and outcomes.

Safety and Dose Escalation Study of Intravenous Zinc Supplementation in Pediatric Critical Illness

BACKGROUND

Critically ill children have low plasma zinc (pZn), correlating with organ failure. Since Zn influences inflammation, immune function, and glucose control, Zn supplementation is a plausible therapeutic modality. We sought to determine a safe dose of intravenous (IV) Zn to restore pZn in critically ill children.

METHODS

Stepwise dose escalation study of IV Zn supplementation at a tertiary children's hospital. All children (<10 years) admitted to the pediatric intensive care unit with a Pediatric Risk of Mortality III score >5, or ≥1 new organ failure were eligible. After consent, patients were sequentially enrolled into 4 dosing groups: (1) no zinc, (2) Zn250: 250 mcg/kg/d ZnSO4, (3) Zn500: 500 mcg/kg/d ZnSO4, or (4) Zn750: 750 mcg/kg/d ZnSO4 ZnSO4 was administered 3 times daily for 7 days. pZn was measured at baseline, end of first ZnSO4 infusion, 1 hour postinfusion, and 7 hours postinfusion on day 1, then daily through days 2-7. Interleukin-6 (IL-6), C-reactive protein (CRP), and lymphocyte subsets were measured on days 1 and 3. Glucose was measured 3 times daily for 7 days.

RESULTS

Twenty-four patients were enrolled. Baseline demographics were similar among groups. Baseline pZn was low in all patients (mean [SD], 41.8 [16.0] mcg/dL). pZn increased over the study period in supplemented groups; however, mean pZn in the Zn750 group exceeded the 50th percentile. pZn was not associated with IL-6, CRP, or lymphocyte subsets among groups. Degree of hyperglycemia did not differ among groups. No patient had a study-related adverse event.

CONCLUSIONS

IV zinc supplementation at 500 mcg/kg/d restores pZn to near the 50th percentile and is well tolerated.

Metabolic and nutritional support of critically ill patients: consensus and controversies

The results of recent large-scale clinical trials have led us to review our understanding of the metabolic response to stress and the most appropriate means of managing nutrition in critically ill patients. This review presents an update in this field, identifying and discussing a number of areas for which consensus has been reached and others where controversy remains and presenting areas for future research. We discuss optimal calorie and protein intake, the incidence and management of re-feeding syndrome, the role of gastric residual volume monitoring, the place of supplemental parenteral nutrition when enteral feeding is deemed insufficient, the role of indirect calorimetry, and potential indications for several pharmaconutrients.

Global perspectives on trace element requirements

Trace elements are inorganic constituents of the human body present in concentrations less than 50mg/kg body weight. An exception is iron that is found in slightly higher amounts, 60 mg/kg body weight, but it is classified within this category due to its physiological roles. Requirements of trace elements can vary according to age, gender, growth, body composition, genetics, pregnancy, lactation, wound healing and burns, alcohol abuse, infections, and diseases (anemia, coronary artery, Keshan, Kashin-Beck). Additionally, interactions may occur with dietary factors, such as other minerals (iron versus copper), phytates (zinc), oxalates (iron), fiber (manganese), and polyphenolic compounds (molybdenum). On a global basis, requirements can vary according to soil and geographical location, food preparation and processing, food accessibility, cultural practices (geophagia) and pollution. Furthermore, global differences exist in body composition, ethnicity, and age of menarche.

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.

Micronutrients, Arginine, and Glutamine: Does Supplementation Provide an Efficient Tool for Prevention and Treatment of Different Kinds of Wounds?

Significance: Wound-healing complications are a clinical problem with a considerable socioeconomic burden. Since several nutrients play a physiological role in wound healing, supplementation of these nutrients may improve wound healing. Recent Advances: Oral nutritional supplements and enteral formulas providing arginine, glutamine, and micronutrients such as ascorbic acid and zinc should improve the healing of pressure ulcers (PU) and the healing of surgical, traumatic, and burned wounds. Is their efficacy proved from clinical intervention trials? Critical Issues: Formulas that are rich in energy, protein, arginine, vitamin C, and zinc can improve PU healing, whereas their efficacy for PU prevention is less clear. High-dose supplementation of vitamin C, zinc, and pantothenic acid may improve the healing of surgical wounds in healthy subjects. Arginine lowers the risk of fistulas in patients undergoing elective surgery due to gastrointestinal cancer. However, formulations also enriched with n-3-fatty acids and ribonucleic acids lower the risk of several wound complications, thus being more effective than isolated arginine. Glutamine and antioxidant micronutrients (vitamin C and E, zinc, selenium, and copper) can improve the healing of surgical, traumatic, and burned wounds. Future Directions: Considerable evidence suggests that formulations, indicated especially for critically ill patients, support the healing of PU and the healing of surgical and burned wounds. However, their optimal composition with regard to the dose of individual components has to be determined in future studies. Further well-designed trials should investigate the impact of certain nutrients for the prevention of PU and for the healing of surgical wounds in healthy subjects.

Micronutrients and superoxide dismutase in postmenopausal women with chronic periodontitis: a pilot interventional study

Purpose

The study was aimed at investigating changes in periodontal parameters and superoxide dismutase activity triggered by root surface debridement with and without micronutrient supplementation in postmenopausal women.

Methods

Forty-three postmenopausal chronic periodontitis patients were divided into two groups: group 1 (n=22) were provided periodontal treatment in the form of scaling and root planing (SRP) and group 2 (n=21) patients received SRP along with systemic administration of micronutrient antioxidants. Patients in both groups were subjected to root surface debridement. Group 2 patients also received adjunctive micronutrient antioxidant supplementation. Serum and salivary superoxide dismutase (SOD) activity along with periodontal parameters were recorded at baseline and 3 months after therapy.

Results

Salivary and serum SOD values significantly (P<0.05) improved with periodontal treatment. Improvement in systemic enzymatic antioxidant status along with reduction in gingival inflammation and bleeding on probing (%) sites was significantly greater in group 2 as compared to group 1.

Conclusions

Adjunctive micronutrient supplements reduce periodontal inflammation and improve the status of systemic enzymatic antioxidants in postmenopausal women.

Graphical Abstract

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.

Burns in children: standard and new treatments

Outcomes of patients with burns have improved substantially over the past two decades. Findings from a 2012 study in The Lancet showed that a burn size of more than 60% total body surface area burned (an increase from 40% a decade ago) is associated with risks and mortality. Similar data have been obtained in adults and elderly people who have been severely burned. We discuss recent and future developments in burn care to improve outcomes of children.

Carnitine deficiency in chronic critical illness

PURPOSE OF REVIEW

New insight in mitochondrial physiology has highlighted the importance of mitochondrial dysfunction in the metabolic and neuroendocrine changes observed in patients presenting with chronic critical illness. This review highlights specifically the importance of carnitine status in this particular patient population and its impact on beta-oxidation and mitochondrial function.

RECENT FINDINGS

The main function of carnitine is long chain fatty acid esterification and transport through the mitochondrial membrane. Carnitine depletion should be suspected in critically ill patients with risk factors such as prolonged continuous renal replacement therapy or chronic parenteral nutrition, and evidence of beta-oxidation impairments such as inappropriate hypertriglyceridemia or hyperlactatemia. When fatty acid oxidation is impaired, acyl-CoAs accumulate and deplete the CoA intramitochondrial pool, hence causing a generalized mitochondrial dysfunction and multiorgan failure, with clinical consequences such as muscle weakness, rhabdomyolysis, cardiomyopathy, arrhythmia or sudden death. In such situations, carnitine plasma levels should be measured along with a complete assessment of plasma amino acid, plasma acylcarnitines and urinary organic acid analysis. Supplementation should be initiated if below normal levels (20 μmol/l) of carnitine are observed. In the absence of current guidelines, we recommend an initial supplementation of 0.5-1 g/day.

SUMMARY

Metabolic modifications associated with chronic critical illness are just being explored. Carnitine deficiency in critically ill patients is one aspect of these profound and complex changes associated with prolonged stay in ICU. It is readily measurable in the plasma and can easily be substituted if needed, although guidelines are currently missing.

Immunonutrition as an adjuvant therapy for burns

BACKGROUND

With burn injuries involving a large total body surface area (TBSA), the body can enter a state of breakdown, resulting in a condition similar to that seen with severe lack of proper nutrition. In addition, destruction of the effective skin barrier leads to loss of normal body temperature regulation and increased risk of infection and fluid loss. Nutritional support is common in the management of severe burn injury, and the approach of altering immune system activity with specific nutrients is termed immunonutrition. Three potential targets have been identified for immunonutrition: mucosal barrier function, cellular defence and local or systemic inflammation. The nutrients most often used for immunonutrition are glutamine, arginine, branched-chain amino acids (BCAAs), omega-3 (n-3) fatty acids and nucleotides.

OBJECTIVES

To assess the effects of a diet with added immunonutrients (glutamine, arginine, BCAAs, n-3 fatty acids (fish oil), combined immunonutrients or precursors to known immunonutrients) versus an isonitrogenous diet (a diet wherein the overall protein content is held constant, but individual constituents may be changed) on clinical outcomes in patients with severe burn injury.

SEARCH METHODS

The search was run on 12 August 2012. We searched the Cochrane Injuries Group's Specialised Register, The Cochrane Library, MEDLINE (OvidSP), Embase (OvidSP), ISI WOS SCI-EXPANDED & CPCI-S and four other databases. We handsearched relevant journals and conference proceedings, screened reference lists and contacted pharmaceutical companies. We updated this search in October 2014, but the results of this updated search have not yet been incorporated.

SELECTION CRITERIA

Randomised controlled trials comparing the addition of immunonutrients to a standard nutritional regimen versus an isonitrogenated diet or another immunonutrient agent.

DATA COLLECTION AND ANALYSIS

Two review authors were responsible for handsearching, reviewing electronic search results and identifying potentially eligible studies. Three review authors retrieved and reviewed independently full reports of these studies for inclusion. They resolved differences by discussion. Two review authors independently extracted and entered data from the included studies. A third review author checked these data. Two review authors independently assessed the risk of bias of each included study and resolved disagreements through discussion or consultation with the third and fourth review authors. Outcome measures of interest were mortality, hospital length of stay, rate of burn wound infection and rate of non-wound infection (bacteraemia, pneumonia and urinary tract infection).

MAIN RESULTS

We identified 16 trials involving 678 people that met the inclusion criteria. A total of 16 trials contributed data to the analysis. Of note, most studies failed to report on randomisation methods and intention-to-treat principles; therefore study results should be interpreted with caution. Glutamine was the most common immunonutrient and was given in seven of the 16 included studies. Use of glutamine compared with an isonitrogenous control led to a reduction in length of hospital stay (mean stay -5.65 days, 95% confidence interval (CI) -8.09 to -3.22) and reduced mortality (pooled risk ratio (RR) 0.25, 95% CI 0.08 to 0.78). However, because of the small sample size, it is likely that these results reflect a false-positive effect. No study findings suggest that glutamine has an effect on burn wound infection or on non-wound infection. All other agents investigated showed no evidence of an effect on mortality, length of stay or burn wound infection or non-wound infection rates.

AUTHORS' CONCLUSIONS

Although we found evidence of an effect of glutamine on mortality reduction, this finding should be taken with care. The number of study participants analysed in this systematic review was not sufficient to permit conclusions that recommend or refute the use of glutamine. Glutamine may be effective in reducing mortality, but larger studies are needed to determine the overall effects of glutamine and other immunonutrition agents.

Immunonutrition: Role in Wound Healing and Tissue Regeneration

Significance: The role of immunonutrition in wound healing has been an area of both interest and controversy for many years. Although deficiencies in certain nutrients have long been known to impair healing, supplementation of specific immune modulating nutrients has not consistently yielded improvements in wound healing. Still, the prospect of optimizing nutrition to assist the immune system in wound repair bears great significance in both medical and surgical fields, as the costs of wound care and repair cannot be ignored. Recent Advances: Recent studies have rekindled efforts to elucidate the roles of specific immunonutrients, and we now have a better understanding of the conditionally essential role of various nutrients such as arginine, which becomes essential in certain clinical situations such as for the trauma patient or patients at high risk for malnutrition. Immunonutrition in its current formulation usually includes supplementation with arginine, glutamine, omega-3 fatty acids, vitamins, and trace minerals, and its use has often been associated with decreased infectious complications and sometimes with improvements in wound healing. Critical Issues: A key to understanding the role of immunonutrition in wound healing is recognizing the distinct contributions and importance of the various elements utilized. Future Directions: Critical areas for future study include identifying the specific populations, timing, and ideal composition of immunomodulating diets in order to optimize the wound healing process.

Zinc, copper, and selenium tissue levels and their relation to subcutaneous abscess, minor surgery, and wound healing in humans

Trace element involvement in wounds left to heal by secondary intention needs clarification. We have previously reported faster healing of wounds following acute surgery compared with elective excision of pilonidal sinus disease. The effect of topical zinc on the closure of the excisional wounds was mediocre compared with placebo. In contrast, parenteral zinc, copper, and selenium combined appear effective for wound healing in humans. We have investigated zinc, copper, and selenium with respect to (a) impact of acute versus chronic pilonidal sinus and (b) regional concentrations within granulating wounds treated topically with placebo or zinc in 42 (33 males) pilonidal disease patients. Baseline serum and skin concentrations of copper correlated (r S = 0.351, p = 0.033, n = 37), but not of zinc or selenium. Patients with abscesses had elevated serum C-reactive protein (CRP) and copper levels (+29 %; p < 0.001) compared with the elective patients consistent with the strong correlation between serum copper and CRP (r S = 0.715, p < 0.0005, n = 41). Seven days after elective surgery, serum CRP and copper levels were elevated (p = 0.010) versus preoperative values. The copper concentration in wound edges was higher than in periwound skin (p < 0.0005) and wound base (p = 0.010). Selenium levels were increased in wound edge compared to wound base (p = 0.003). Topical zinc oxide treatment doubled (p < 0.050) zinc concentrations in the three tissue localizations without concomitant significant changes of copper or selenium levels. In conclusion, copper and selenium are mobilized to injured sites possibly to enhance host defense and early wound healing mechanisms that are complementary to the necessity of zinc for matrix metalloproteinase activity.

The use of antioxidants in radiotherapy-induced skin toxicity

Radiation-induced skin damage is one of the most common complications of radiotherapy. In order to combat these side effects, patients often turn to alternative therapies, which often include antioxidants. Antioxidants such as those in the polyphenol chemical class, xanthine derivatives, tocepherol, sucralfate, and ascorbate have been studied for their use in either preventing or treating radiotherapy-induced skin damage. Apart from their known role as free radical scavengers, some of these antioxidants appear to alter cytokine release affecting cutaneous and systemic changes. We review the role of antioxidants in treating and preventing radiation-induced skin damage as well as the possible complications of using such therapy.

Antioxidant micronutrients in the critically ill: a systematic review and meta-analysis

INTRODUCTION

Critical illness is characterized by oxidative stress, which is a major promoter of systemic inflammation and organ failure due to excessive free radical production, depletion of antioxidant defenses, or both. We hypothesized that exogenous supplementation of trace elements and vitamins could restore antioxidant status, improving clinical outcomes.

METHODS

We searched computerized databases, reference lists of pertinent articles and personal files from 1980 to 2011. We included randomized controlled trials (RCTs) conducted in critically ill adult patients that evaluated relevant clinical outcomes with antioxidant micronutrients (vitamins and trace elements) supplementation versus placebo.

RESULTS

A total of 21 RCTs met inclusion criteria. When the results of these studies were statistically aggregated (n = 20), combined antioxidants were associated with a significant reduction in mortality (risk ratio (RR) = 0.82, 95% confidence interval (CI) 0.72 to 0.93, P = 0.002); a significant reduction in duration of mechanical ventilation (weighed mean difference in days = -0.67, 95% CI -1.22 to -0.13, P = 0.02); a trend towards a reduction in infections (RR= 0.88, 95% CI 0.76 to 1.02, P = 0.08); and no overall effect on ICU or hospital length of stay (LOS). Furthermore, antioxidants were associated with a significant reduction in overall mortality among patients with higher risk of death (>10% mortality in control group) (RR 0.79, 95% CI 0.68 to 0.92, P = 0.003) whereas there was no significant effect observed for trials of patients with a lower mortality in the control group (RR = 1.14, 95% 0.72 to 1.82, P = 0.57). Trials using more than 500 μg per day of selenium showed a trend towards a lower mortality (RR = 0.80, 95% CI 0.63 to 1.02, P = 0.07) whereas trials using doses lower than 500 μg had no effect on mortality (RR 0.94, 95% CI 0.67 to 1.33, P = 0.75).

CONCLUSIONS

Supplementation with high dose trace elements and vitamins may improve outcomes of critically ill patients, particularly those at high risk of death.

Review of Intravenous Selenium Infusions for the Critically III Patient

Attempts to improve mortality for patients with sepsis, severe sepsis, systemic inflammatory response syndrome, and septic shock continue to challenge health care professionals. This review will explore how the antioxidant, and possibly pro-oxidant, properties of selenium may benefit critically ill patients. Literature examining improvements in clinical outcomes from intravenous (IV) selenium infusion therapy will be discussed. Although there is not an overwhelming amount of knowledge about IV selenium and its effect on morbidity and mortality, this review will outline recent research evaluating the use of IV selenium infusions and its potential to decrease morbidity and mortality for different critically ill patient populations.

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.

Functional late outgrowth endothelial progenitors isolated from peripheral blood of burned patients

BACKGROUND

Bioengineered skin substitutes are increasingly considered as a useful option for the treatment of full thickness burn injury. Their viability following grafting can be enhanced by seeding the skin substitute with late outgrowth endothelial progenitor cells (EPCs). However, it is not known whether autologous EPCs can be obtained from burned patients shortly after injury.

METHODS

Late outgrowth EPCs were isolated from peripheral blood sampled obtained from 10 burned patients (extent 19.6±10.3% TBSA) within the first 24h of hospital admission, and from 7 healthy subjects. Late outgrowth EPCs were phenotyped in vitro.

RESULTS

In comparison with similar cells obtained from healthy subjects, growing colonies from burned patients yielded a higher percentage of EPC clones (46 versus 17%, p=0.013). Furthermore, EPCs from burned patients secreted more vascular endothelial growth factor (VEGF) into the culture medium than did their counterparts from healthy subjects (85.8±56.2 versus 17.6±14pg/mg protein, p=0.018). When injected to athymic nude mice 6h after unilateral ligation of the femoral artery, EPCs from both groups of subjects greatly accelerated the reperfusion of the ischaemic hindlimb and increased the number of vascular smooth muscle cells.

CONCLUSIONS

The present study supports that, in patients with burns of moderate extension, it is feasible to obtain functional autologous late outgrowth EPCs from peripheral blood. These results constitute a strong incentive to pursue approaches based on using autotransplantation of these cells to improve the therapy of full thickness burns.

Evolving changes in the management of burns and environmental injuries

Burns and environmental injuries are common as primary or secondary problems in survivors of natural disasters, terrorist incidents, and combat operations. In recent years, intensive military medical experience has resulted in substantial progress in treatment of these important problems. This article reviews practical applications of this new knowledge.

Pancreatic stone protein as an early biomarker predicting mortality in a prospective cohort of patients with sepsis requiring ICU management

Introduction

Biomarkers, such as C-reactive protein [CRP] and procalcitonin [PCT], are insufficiently sensitive or specific to stratify patients with sepsis. We investigate the prognostic value of pancreatic stone protein/regenerating protein (PSP/reg) concentration in patients with severe infections.

Methods

PSP/reg, CRP, PCT, tumor necrosis factor-alpha (TNF-α), interleukin 1 beta (IL1-β), IL-6 and IL-8 were prospectively measured in cohort of patients ≥ 18 years of age with severe sepsis or septic shock within 24 hours of admission in a medico-surgical intensive care unit (ICU) of a community and referral university hospital, and the ability to predict in-hospital mortality was determined.

Results

We evaluated 107 patients, 33 with severe sepsis and 74 with septic shock, with in-hospital mortality rates of 6% (2/33) and 25% (17/74), respectively. Plasma concentrations of PSP/reg (343.5 vs. 73.5 ng/ml, P < 0.001), PCT (39.3 vs. 12.0 ng/ml, P < 0.001), IL-8 (682 vs. 184 ng/ml, P < 0.001) and IL-6 (1955 vs. 544 pg/ml, P < 0.01) were significantly higher in patients with septic shock than with severe sepsis. Of note, median PSP/reg was 13.0 ng/ml (IQR: 4.8) in 20 severely burned patients without infection. The area under the ROC curve for PSP/reg (0.65 [95% CI: 0.51 to 0.80]) was higher than for CRP (0.44 [0.29 to 0.60]), PCT 0.46 [0.29 to 0.61]), IL-8 (0.61 [0.43 to 0.77]) or IL-6 (0.59 [0.44 to 0.75]) in predicting in-hospital mortality. In patients with septic shock, PSP/reg was the only biomarker associated with in-hospital mortality (P = 0.049). Risk of mortality increased continuously for each ascending quartile of PSP/reg.

Conclusions

Measurement of PSP/reg concentration within 24 hours of ICU admission may predict in-hospital mortality in patients with septic shock, identifying patients who may benefit most from tailored ICU management.

[Guidelines for specialized nutritional and metabolic support in the critically-ill patient. Update. Consensus of the Spanish Society of Intensive Care Medicine and Coronary Units-Spanish Society of Parenteral and Enteral Nutrition (SEMICYUC-SENPE): critically-burned patient]

The response to severe burns is characterized by hypermetabolism (the most hypermetabolic existing model of aggression) and hypercatabolism, with a high degree of destruction of the skeletal musculature. Metabolic disorders are most evident in the first two weeks after the burn, although they can be prolonged in direct relation to the complications that these patients develop. Nutritional-metabolic support is an essential part of the treatment of these patients and should be started early, preferentially through the enteral route, with parenteral nutrition as complementary support. Exact calculation of calorie-protein requirements in these patients is difficult, even when indirect calorimetry is used, due to the high loss of proteins and CO(2) through the skin. Specific pharmaconutrients are indicated, with a high dose of micronutrients. The use of drugs or medications with anabolic effects is also sometimes indicated.

Standardizing the diagnosis of inhalation injury using a descriptive score based on mucosal injury criteria

INTRODUCTION

Inhalation injury is an important determinant of outcome in patients with major burns. However the diagnostic criteria remain imprecise, preventing objective comparisons of published data. The aims were to evaluate the utility of an inhalation score based on mucosal injury, while assessing separately the oro-pharyngeal sphere (ENT) and tracheobronchial tree (TB) in patients admitted to the ICU with a suspicion of inhalation injury.

METHODS

Prospective observational study in 100 patients admitted with suspicion of inhalation injury among 168 consecutive burn admissions to the ICU of a university hospital. Inclusion criteria, endoscopic airway assessment during the first hours. ENT/TB lesion grading was 1: oedema, hyperemia, hypersecretion, 2: bullous mucosal detachment, erosion, exudates, 3: profound ulcers, necrosis.

RESULTS

Of the 100 patients (age 42±17 years, burns 23±19%BSA), 79 presented an ENT inhalation injury ≥ENT1 (soot present in 24%): 36 had a tracheobronchial extension, 33 having a grade ≥TB1. Burned vibrissae: 10 patients "without" suffered ENT injury, while 6 patients "with" had no further lesions. Length of mechanical ventilation was strongly associated with the first 24 hrs' fluid resuscitation volume (p<0.0001) and the presence of inhalation injury (p=0.03), while the ICU length of stay was correlated with the %BSA. Soot was associated with prolonged mechanical ventilation (p=0.0115). There was no extubation failure.

CONCLUSIONS

The developed inhalation score was simple to use, providing a unified language, and drawing attention to upper airway involvement. Burned vibrissae and suspected history proved to be insufficient diagnostic criteria. Further studies are required to validate the score in a larger population.

Oxidative stress

Oxidative stress is defined by an imbalance between increased levels of reactive oxygen species (ROS) and a low activity of antioxidant mechanisms. An increased oxidative stress can induce damage to the cellular structure and potentially destroy tissues. However, ROS are needed for adequate cell function, including the production of energy by the mitochondria. Increased oxidative stress has been incriminated in physiological conditions, such as aging and exercise, and in several pathological conditions, including cancer, neurodegenerative diseases, cardiovascular diseases, diabetes, inflammatory diseases, and intoxications. However, prevention by antioxidants has been mostly inefficient. Therefore, a rigorous scientific evaluation in well-defined conditions is mandatory to define the appropriate place for manipulations of the oxidative pathways in human medicine.

Micronutrient supplementation for critically ill adults: a systematic review and meta-analysis

OBJECTIVE

This systematic review assessed the effects of micronutrient supplementation on adults recovering from critical illness. Primary outcomes included clinical endpoints (mortality, infectious complications, length of intensive care unit and of hospital stay). Secondary outcomes included descriptions of practice issues, micronutrient status, morbidity, course of the acute-phase response, and oxidative stress.

METHODS

Electronic bibliographic databases, bibliographies of retrieved articles, and personal files were searched and reviewed. Randomized controlled trials (RCTs) of micronutrient supplementation in adult critically ill patients administered enterally and/or parenterally in addition to their routine care were included. Two authors independently extracted data and assessed trial quality. The random-effects model was used to estimate overall relative risk (RR)/mean difference and effect size. P<0.05 was considered statistically significant.

RESULTS

Fifteen (n=1714) and 18 (n=1849) RCTs were included for the primary and secondary objectives, respectively. Fourteen trials (n=1468) showed a statistically significant decrease in overall mortality (RR 0.78, 95% confidence interval 0.67-0.90, I2=0%, P=0.0009). Six RCTs (n=1194) indicated a statistically significant decrease in 28-d mortality (RR 0.75, 95% confidence interval 0.63-0.88, I2=0%, P=0.0006). Micronutrient supplementation was not associated with a decrease in infectious complications, length of intensive care unit, or length of hospital stay. In subgroup analyses, a sensitivity analysis of combined micronutrients indicated a significant decrease in mortality (RR 0.69, 95% confidence interval 0.54-0.90, I2=2%, P=0.006). The secondary outcomes confirmed that timing, duration, and dosing appear to be key factors to ensure optimal clinical benefit.

CONCLUSION

This review does suggest a potential benefit of micronutrient supplementation in critically ill adults by possibly being associated with a decrease in mortality.

Nutrition in burns: Galveston contributions

Aggressive nutrition support is recommended following severe burn injury. Initially, such injury results in a prolonged and persistent hypermetabolic response mediated by a 10- to 20-fold elevation in plasma catecholamines, cortisol, and inflammatory mediators. This response leads to twice-normal metabolic rates, whole-body catabolism, muscle wasting, and severe cachexia. Thus, it is relevant to review the literature on nutrition in burns to adjust/update treatment. Failure to meet the increased substrate requirements may result in impaired wound healing, multiorgan dysfunction, increased susceptibility to infection, and death. Therefore, aggressive nutrition support is essential to ensure adequate burn care, attenuate the hypermetabolic response, optimize wound healing, minimize devastating catabolism, and reduce morbidity and mortality. Here, the authors provide nutrition recommendations gained from prospective trials, retrospective analyses, and expert opinions based on the authors' practices in Galveston, Texas, and Vienna, Austria.

Stressor states and the cation crossroads

Neurohormonal activation involving the hypothalamic-pituitary-adrenal axis and adrenergic nervous and renin-angiotensin-aldosterone systems is integral to stressor state-mediated homeostatic responses. The levels of effector hormones, depending upon the degree of stress, orchestrate the concordant appearance of hypokalemia, ionized hypocalcemia and hypomagnesemia, hypozincemia, and hyposelenemia. Seemingly contradictory to homeostatic responses wherein the constancy of extracellular fluid would be preserved, upregulation of cognate-binding proteins promotes coordinated translocation of cations to injured tissues, where they participate in wound healing. Associated catecholamine-mediated intracellular cation shifts regulate the equilibrium between pro-oxidants and antioxidant defenses, a critical determinant of cell survival. These acute and chronic stressor-induced iterations in extracellular and intracellular cations are collectively referred to as the cation crossroads. Intracellular cation shifts, particularly excessive accumulation of Ca2+, converge on mitochondria to induce oxidative stress and raise the opening potential of their inner membrane permeability transition pores (mPTPs). The ensuing loss of cationic homeostasis and adenosine triphosphate (ATP) production, together with osmotic swelling, leads to organellar degeneration and cellular necrosis. The overall impact of iterations in extracellular and intracellular cations and their influence on cardiac redox state, cardiomyocyte survival, and myocardial structure and function are addressed herein.

Diet in dermatology: present perspectives

Many nutrients are essential for life, and an adequate amount of nutrients in the diet is necessary for providing energy, building and maintaining body organs, and for various metabolic processes. The role of food in the induction of various skin disorders and skin diseases leading to nutritional deficiencies is well known. The photo-protective potential of antioxidants, the effects of micronutrient supplementation on the skin immune system, and the modulating effects of fatty acids on skin disorders are well documented. Skin diseases due to nutritional deficiencies, the dietary role in skin immunity and various skin diseases, and the role of antioxidants and other supplements in skin health have been reviewed.

Volatile constituents, inorganic elements and primary screening of bioactivity of black coral cigarette holders

Black corals (BC) have been used for a long time in Chinese medicine, and may have some pharmaceutical functions when used as material for cigarette holders in southeast China. This study is aimed to investigate the bioactivities of volatile constituents in BC and to explore the folklore behind the use of BC cigarette holders (BCCHs). We extracted the volatile constituents of BC by supercritical fluid extraction (SFE) with carbon dioxide (CO₂-SFE), then identified and analyzed the constituents by gas chromatography-mass spectrometry (GC-MS). In total, 15 components were reliably identified in BC and found to be biologically active. These included triethyl phosphate, butylated hydroxytoluene, cedrol, n-hexadecanoic acid, squalene, and cholesterol. Meanwhile 13 inorganic elements (P, Ca, Mg, S, B, Si, Fe, Cu, Zn, Ba, etc.) were determined by inductively coupled plasma spectrometer (ICPS). In the bioactivity tests, the BC extract (BCE) showed a scavenging activity of 2,2-diphenyl-1-picrylhydrazyl free radicals and hydroxyl radicals by phenanthroline-Fe (II) oxidation and moderate inhibition of Gram-positive microorganisms. The antioxidant and antimicrobial activities of BC, which are related to the active chemical composition, may explain the perceived benefit for cigarette smokers who use BCCHs.

Cation dyshomeostasis and cardiomyocyte necrosis: the Fleckenstein hypothesis revisited

An ongoing loss of cardiomyocytes to apoptotic and necrotic cell death pathways contributes to the progressive nature of heart failure. The pathophysiological origins of necrotic cell loss relate to the neurohormonal activation that accompanies acute and chronic stressor states and which includes effector hormones of the adrenergic nervous system. Fifty years ago, Albrecht Fleckenstein and coworkers hypothesized the hyperadrenergic state, which accompanies such stressors, causes cardiomyocyte necrosis based on catecholamine-initiated excessive intracellular Ca(2+) accumulation (EICA), and mitochondrial Ca(2+) overloading in particular, in which the ensuing dysfunction and structural degeneration of these organelles leads to necrosis. In recent years, two downstream factors have been identified which, together with EICA, constitute a signal-transducer-effector pathway: (i) mitochondria-based induction of oxidative stress, in which the rate of reactive oxygen metabolite generation exceeds their rate of detoxification by endogenous antioxidant defences; and (ii) the opening of the mitochondrial inner membrane permeability transition pore (mPTP) followed by organellar swelling and degeneration. The pathogenesis of stress-related cardiomyopathy syndromes is likely related to this pathway. Other factors which can account for cytotoxicity in stressor states include: hypokalaemia; ionized hypocalcaemia and hypomagnesaemia with resultant elevations in parathyroid hormone serving as a potent mediator of EICA; and hypozincaemia with hyposelenaemia, which compromise antioxidant defences. Herein, we revisit the Fleckenstein hypothesis of EICA in leading to cardiomyocyte necrosis and the central role played by mitochondria.