The impact of serum zinc normalization on clinical outcomes in severe burn patients.

INTRODUCTION: Patients with thermal burns become zinc deficient due to exudative losses, increased urinary excretion, and reduction of carrier proteins which results in impaired immunity, wound healing and glucose control. Previous trials have demonstrated improved wound healing utilizing fixed zinc supplementation, but none have assessed the potential benefits associated with normalizing serum zinc concentrations. The objective of this study was to compare the impact of zinc normalization on clinical outcomes in patients with severe thermal burns. METHODS: This retrospective, single-center study of patients with at least 10% total body surface area (TBSA) burn and three serum zinc concentrations compared the ratio of hospital length of stay (LOS) over TBSA burned (LOS/TBSA index) between those with normal (≥60 mcg/mL) and non-normal (<60 mcg/mL) serum zinc concentrations; delineated by the third measurement. Secondary outcomes were time to 90% epithelialization, infection incidence, and percentage of blood glucose values greater than 180 mg/dL. Data are reported as median [25-75% interquartile range] for continuous variables and frequency (percent) for categorical variables. RESULTS: A total of 56 patients were included for evaluation (11 normal and 45 non-normal). Burn size was 20.5% TBSA [11-29] for those with normal zinc and 27.3% [22-36] for non-normal; number of grafts for each group was 1 [0-1] vs 2 [1-3] respectively. LOS/TBSA index did not differ significantly between groups (1.10 normal vs. 1.21 non-normal, unadjusted p = 0.69; p = 0.75 adjusting for number of grafts). Time to 90% epithelialization was reduced in the normal group (27.5 vs. 57 days, p = 0.02), but this did not remain statistically significant after adjustment for %TBSA and number of grafts (p = 0.18). The groups did not differ significantly in incidence of infection or hyperglycemia in either unadjusted or adjusted analyses. CONCLUSIONS: This was the first study, to our knowledge, to assess the clinical impact of normalizing serum zinc levels in patients with severe burns. Our results suggest the normalization of serum zinc levels through individualized zinc supplementation is not associated with improvement in clinical outcomes during hospitalization and therefore fixed-dose zinc supplementation without acquisition of serum zinc measurements should be considered.

A clinician's guide to the treatment of foot burns occurring in diabetic patients.

INTRODUCTION: Diabetes mellitus affects 25.8 million Americans and is predicted to almost double by 2050. The presence of diabetes complicates hospital courses because of the microvascular complications associated with disease progression. Patients with diabetes represent 18.3% of annual burn admissions to our unit and 27% have burns to the feet. The purpose of this project was to develop an evidence-based guideline for care of the patient with diabetes and foot burns METHODS: A multidisciplinary group was charged with developing an evidence-based guideline for the treatment of foot burns in patients with diabetes. Evidence was evaluated in the areas of diabetes, burn care, hyperbaric medicine, care of diabetic foot wounds and physical therapy. After guideline development and approval, key aspects were incorporated into order sets. RESULTS: Key aspects of this guideline are the ability to identify patients with undiagnosed diabetes, assess diabetic control, optimize glycemic and metabolic control, optimize burn wound management, treat microvascular disease, and provide education and a discharge plan. Evaluated outcomes are glycemic control, length of stay, complication rates, amputation rates, infection rates and the use of hyperbaric oxygen. CONCLUSIONS: Best outcomes for this high risk population will be attainable with an evidence based guideline.

Altered processing of sweet taste in the brain of diet soda drinkers.

Artificially sweetened beverage consumption has been linked to obesity, and it has been hypothesized that considerable exposure to nonnutritive sweeteners may be associated with impaired energy regulation. The reward system plays an integral role in modulating energy intake, but little is known about whether habitual use of artificial sweetener (i.e., diet soda consumption) may be related to altered reward processing of sweet taste in the brain. To investigate this, we examined fMRI response after a 12-hour fast to sucrose (a nutritive sweetener) and saccharin (a nonnutritive sweetener) during hedonic evaluation in young adult diet soda drinkers and non-diet soda drinkers. Diet soda drinkers demonstrated greater activation to sweet taste in the dopaminergic midbrain (including ventral tegmental area) and right amygdala. Saccharin elicited a greater response in the right orbitofrontal cortex (Brodmann Area 47) relative to sucrose in non-diet soda drinkers. There was no difference in fMRI response to the nutritive or nonnutritive sweetener for diet soda drinkers. Within the diet soda drinkers, fMRI activation of the right caudate head in response to saccharin was negatively associated with the amount of diet sodas consumed per week; individuals who consumed a greater number of diet sodas had reduced caudate head activation. These findings suggest that there are alterations in reward processing of sweet taste in individuals who regularly consume diet soda, and this is associated with the degree of consumption. These findings may provide some insight into the link between diet soda consumption and obesity.

An update on nutrition support in the critically ill.

Nutrition support in the critically ill patient has shifted from adjunctive toward fundamental therapy with the publication of high-grade evidence. Early enteral nutrition (EN) is recommended because it is associated with decreased infectious complications and use of EN is associated with decreased mortality and infections compared with parenteral nutrition (PN). EN is not without risks, such as diarrhea or aspiration, but use of prokinetic agents, head of bed elevation, and use of feeding protocols can maximize benefits and minimize risks. Although recently high-grade evidence on nutrition support in the critically ill population has been published, many controversies still exist. In obese patients, use of hypocaloric feedings with increased protein has been demonstrated to promote weight loss and improved glucose management. In nonobese patients, small studies have demonstrated that providing more than 70% or less than 30% of goal caloric intake may be associated with worse outcomes, but more studies are needed. Additional research is also needed to conclude whether withholding intravenous fat emulsions for the first 7 to 10 days of PN reduces infectious complications. Finally, more high-quality studies are needed to define the role of immune-enhancing nutrients such as arginine, glutamine, omega-3 fatty acids, zinc, and selenium.

Olfactory and auditory event-related potentials in Huntington's disease.

The influence of Huntington's disease (HD) on the olfactory event-related potential (OERP), an electrophysiological measure of olfactory information processing, has not been reported to date. In the present study, olfactory and auditory event-related potentials (ERPs) were recorded monopolarly from Fz, Cz, and Pz electrode sites in 8 patients with HD and 8 age- and gender-matched control participants. Results demonstrated that individuals with HD were delayed compared with controls on the P3 component of the OERP (p<.001), with a trend toward a significant delay on the auditory ERP P3 (p<.06). The effect size for OERP P3 latency (pi(2)=.72) was larger than that for the auditory P3 (pi(2)=.24), which has previously been shown to be delayed in HD. Patients performed significantly worse than controls did on all neuropsychological measures. These measures significantly correlated with several components of the OERP. These findings extend the understanding of olfactory deficits in HD.