Journal of Parenteral and Enteral Nutrition

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.

Background: Dietary supplements are regularly used by at least half of the American population, yet the health benefits of these agents are unclear. Objective: A systematic review to determine the benefits and risks of dietary supplements in Westernized societies. Data Sources: MEDLINE, Embase, Cochrane Register of Controlled Trials and citation review of relevant articles. Study Selection: Randomized, placebo-controlled clinical trials in non-pregnant Westernized adults that evaluated clinical outcomes of nutritional supplements. Data Extraction: Data were abstracted on study design, study size, study setting, patient population, dietary intervention and clinical outcomes. The outcome of each study was classified as non-beneficial, beneficial or harmful according to whether theend-point(s) of interest reached statistical significance. Data Synthesis: Sixty-three studies met the criteria for our systematic review. No benefit was recorded in 45 studies, with 10 of these showing a trend towards harm and with two showing a trend towards benefit. Four studies reported harm with increased cancer deaths (n=2) and increased fractures (n=2). Two studies reported both a harmful as well as a beneficial outcome. A beneficial outcome was reported in 12 studies; 6 which studied vitamin D and three which investigated omega-3 fatty acids. While a benefit was reported in one study each which investigated Vitamin E, folic acid and Ginkgo biloba this benefit was not confirmed by larger and more adequately powered studies. Conclusions: With the possible exceptions of Vitamin D and omega-3 fatty acids there is no data to support the widespread use of dietary supplements in Westernized populations; indeed, many of these supplements may be harmful.

Background: The incidence of bloodstream infection (BSI) among patients receiving parenteral nutrition (PN) is reported to vary widely from 1.3%−39%. BSI rates in a large inpatient population were compared in this study to determine if PN prepared by different methods was associated with BSI. Methods: Data from Premier Perspective, the largest inpatient cost-based clinical and financial claims database in the United States, were analyzed. Included were all hospitalized patients age ≥18 years who received any PN from January 1, 2005, to December 31, 2007. BSI rates, the primary dependent variable, were defined as the occurrence ICD-9 codes of 038.x (septicemia), 995.91 (sepsis), 995.92 (severe sepsis), and 790.7 (bacteremia). The exposure cohort received PN in a commercial multichamber bag (MCB) (n = 4669), whereas the comparator group received PN prepared by a pharmacy (either hospital compounded or outsourced; n = 64,315). Observed data were adjusted using multivariate logistic regression for baseline differences, risk factors, and potential confounders, with propensity score matching as a sensitivity analysis. Results: The observed and adjusted BSI rates indicate that MCB is associated with fewer infections than pharmacy-prepared PN (observed 17.5% vs 26.6%; adjusted 19.6% vs 25.9%, both P < .001). Propensity-matched scores found similar results with observed BSI rates of 18.9% in patients receiving MCB and 24.6% in patients receiving a compounded PN. Conclusion: Both the observed rate of BSI and adjusted probability of developing a BSI remained significantly lower for the MCB than the compounded PN group.

Background: Critically ill children differ in their energy needs from healthy children in terms of underlying metabolic derangement, comorbidities, energy reserve, and response to illness. This study determined how many pediatric intensive care unit (PICU) patients were candidates for indirect calorimetry (IC), per American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) recommendations. Methods: Admission diagnosis, demographics, type/amount of nutrition support, length of intensive care unit/hospital stay were collected. Patients were classified as candidates for IC per A.S.P.E.N. guidelines. Results: Mean (SD) age of patients (n = 150) was 6.7 (5.6) years, with PICU length of stay of 3.9 (5.3) days. IC was indicated in 72.0% (108/150) of patients during PICU days 1–7. Patients with miscellaneous (50%), neurological (73%), respiratory (81%), sepsis (83%), and oncology (100%) diagnoses were candidates for IC. Underweight/overweight/obese (32.4%), hypermetabolism (26.4%), and not meeting nutrition goals (13.7%) were the most frequent indications for IC (χ², P < .001). Patients (31%) met ≥2 indications for IC. Patients with neurological disease (relative risk [RR], 4.8; 95% confidence interval [CI], 1.7–14.6), oncology patients (4.2; 1.1–15.9), respiratory patients (5.5; 2.0–16.9), and children with sepsis/septic shock/infection (5.6; 1.9–18.1) were more likely to have ≥2 indications for IC compared to those with other diagnoses. Conclusions: Three of 4 patients were candidates for IC per A.S.P.E.N. guidelines. PICUs might have to prioritize performing IC in patients who are <2 years of age, malnourished (underweight/overweight) on admission, or PICU stay of >5 days. Future studies should determine the cost-benefit ratios of performing IC in PICU patients.

Background: The authors investigated whether an insulin protocol for parenteral nutrition (PN)–induced hyperglycemia is superior to conventional management relying primarily on sliding-scale insulin at a large county hospital. Methods: A prospective cohort study with historical controls was completed. Adult patients receiving PN were managed with a protocol that determined insulin doses based on carbohydrate delivery and capillary blood glucose (CBG) if half or more of CBG measurements in the first 24 hours after initiation of PN exceeded 140 mg/dL. Control data were obtained from records of patients who met study eligibility criteria but had been managed before implementation of the insulin protocol. Results: Mean CBG after the start of insulin therapy was 138 ± 37 mg/dL for protocol patients and 159 ± 46 mg/dL for controls (P < .0001). Proportion of CBG values in the target range of 80–140 mg/dL was 60% in the protocol group and 35% in the control group (P < .0001). Hypoglycemia, defined as CBG <80 mg/dL, occurred infrequently but more often in the protocol group (3% vs 1%, P = .012). There was no difference in total daily insulin between groups, although protocol patients received mostly scheduled insulin (93% total daily dose), whereas control patients received predominantly supplemental insulin (66% total daily dose). Conclusions: Protocol-directed management of PN-induced hyperglycemia is superior to ad hoc insulin dosing. Linking insulin to carbohydrate in PN leads to improved glycemic control with a low rate of hypoglycemia.

Background: Altered concentrations of ghrelin, motilin, and cholecystokinin (CCK) may contribute to gastric hypomotility. The aims of this study were to evaluate the concentrations of these hormones in patients tolerant and intolerant to gastric nutrition, assess the influence of prokinetic therapy on these hormone concentrations, determine the associations between these mediators and gastric emptying, and evaluate whether inflammation influences their concentrations. Methods: Post hoc analyses of 2 prospective studies that enrolled 20 critically ill patients with an aspirated gastric residual (GR) >150 mL while receiving gastric enteral nutrition (intolerant group) and 10 critically ill patients with minimal GR (tolerant group). Patients with intolerance were also assessed 1 day after prokinetic therapy. Fasting serum concentrations of total ghrelin, acyl ghrelin (active), des-acyl ghrelin (inactive), motilin, CCK, and tumor necrosis factor (TNF)−α were determined. Gastric emptying was assessed concurrently using the acetaminophen absorption method. Results: Compared to the tolerant group, the intolerant group had higher total ghrelin (1324.8 ± 1204.6 vs 285.1 ± 132.5 pg/mL; P < .001), lower acyl ghrelin (70.5 ± 65.4 vs 208.5 ± 186.9 pg/mL; P < .05), and lower acyl ghrelin to des-acyl ghrelin ratio (1.11 ± 1.35 vs 3.47 ± 3.21 pg/mL; P < .05). Concentrations of other hormones and TNF-α were similar. Despite accelerated gastric emptying after prokinetic therapy, concentrations of all hormones and TNF-α were similar to baseline values. Hormone concentrations were not associated with gastric emptying or TNF-α. Conclusion: Patients intolerant to gastric nutrition generate less acyl ghrelin, which may contribute to gastric hypomotility. Intolerance is not associated with altered concentrations of other hormones. Hormone concentrations are not influenced by prokinetic therapy.

Background: Serum prealbumin (PAB) is commonly used to assess protein status and is often used to monitor the response to nutrition support. However, during inflammation, the liver synthesizes acute-phase proteins such as C-reactive protein (CRP) at the expense of PAB. Objective: The purpose of this retrospective study was to determine whether changes in PAB reflect the delivery of adequate nutrients or changes in inflammatory status in hospitalized adults (≥18 years) receiving enteral nutrition (n = 154). Methods: Protein and energy intake were compared to changes in PAB, assessed at baseline and twice weekly. C-reactive protein was assessed when PAB was <18 mg/dL to determine the presence and severity of inflammation. Results: In a sample of mostly critically ill patients, there was no significant difference in change in PAB for those receiving ≥60% of calorie needs (2.74 ± 9.50 mg/dL) compared to <60% of calorie needs (2.48 ± 9.36 mg/dL; P = .86). Changes in PAB correlated only with changes in CRP (r = -0.544, P < .001). In a subgroup analysis of 62 patients with repeated measures of PAB and CRP, PAB increased significantly only in the bottom 2 tertiles for calorie delivery and the lowest tertile for protein delivery. Conclusions: These results indicate that PAB may not be a sensitive marker for evaluating the adequacy of nutrition support in critically ill patients with inflammation. Only change in CRP was able to significantly predict changes in PAB, suggesting that an improvement in inflammation, rather than nutrient intake, was responsible for the increases in PAB levels.

Background: Successful small intestinal (SI) adaptation following surgical resection is essential for optimizing newborn growth and development, but the potential for adaptation is unknown. The authors developed an SI resection model in neonatal piglets supported by intravenous and enteral nutrition. Methods: Piglets (n = 33, 12–13 days old) were randomized to 80% SI resection with parenteral nutrition feeding (R-PN), 80% SI resection with PN + enteral feeding (R-EN), or sham SI transection with PN + enteral feeding (sham-EN). In resected pigs, the distal 100 cm of ileum (residual SI) and 30 cm of proximal SI were left intact. All pigs received parenteral nutrition postsurgery. Enteral nutrition piglets received continuous gastric infusion of elemental diet from day 3 (40:60 parenteral nutrition:enteral nutrition). Piglets were killed 4, 6, or 10 days postsurgery. Results: By 10 days, R-EN piglets had longer residual SI than R-PN and sham-EN pigs (P < .05). At days 6 and 10, R-EN piglets had greater weight per length of intact SI (P < .05) and isolated mucosa (P < .05) compared to other groups. Greater gut weight in R-EN piglets was facilitated by a greater cellular proliferation index (P < .01) by 4 days compared to other groups and greater overall ornithine decarboxylase activity vs R-PN piglets (P < .05). Conclusions: This new model demonstrated profound SI adaptation, initiated early postsurgery by polyamine synthesis and crypt cell proliferation and only in response to enteral feeding. These changes translated to greater gut mass and length within days, likely improving functional capacity long term.

Aim: To investigate (1) the effect of hyperthermic intraoperative intraperitoneal chemotherapy (HIIC) on intestinal permeability of patients with advanced gastric cancer and (2) the protective effect of postoperative enteral nutrition (EN) on patients. Methods: >All patients were divided randomly into 3 groups: the EN group, treated with EN during postoperative period; the EN+HIIC group, treated with HIIC and postoperative EN; and the PN+HIIC group, treated with HIIC and postoperative parenteral nutrition. The lactulose/mannitol (L/M) ratio was used to evaluate the permeability of intestinal mucous. Results: Compared with the ratio of L/M on the day before operation (POD-1), the ratio of L/M on POD+3 increased significantly in all 3 groups (P < .0001) and then decreased gradually. The L/M ratio of the EN and EN+HIIC groups recovered to the baseline on POD+12. In contrast, the PN+HIIC group still had an elevated L/M ratio until POD+12. The ratios of L/M in the EN+HIIC group on POD+7 and POD+12 were significantly different from those of the PN+HIIC group (0.0855 ± 0.0462 vs 0.1298 ± 0.063, P = .007; 0.0336 ± 0.0235 vs 0.0616 ± 0.0430, P = .038, respectively). Conclusion: Gastric cancer radical resection resulted in a significant increase in intestinal permeability. HIIC aggravated the injury of intestinal mucous permeability, which could be reversed by EN.

Background: The authors aimed to investigate the role of anti–tumor necrosis factor (TNF)–α monoclonal antibody treatment in a mouse model of parenteral nutrition–associated liver disease (PNALD). Methods: C57BL/6J male mice (aged 6–8 weeks) were randomly assigned to 3 groups: parenteral nutrition (PN), PN with anti–TNF-α monoclonal antibody treatment (PN + mAb), and controls. A central venous catheter was inserted for intravenous infusion of a PN solution (PN and PN + mAb groups) or saline (controls) for 7 days. Liver pathology, hepatic biochemical indicators, and serum TNF-α concentrations were analyzed. Levels of hepatic bsep, mdr1a/mdr1b, mdr2, and mrp2 mRNA were also evaluated in each group. Results: The PN group showed significant increases in serum transaminase, direct bilirubin, and bile acids relative to the control group (P < .05). Histopathological changes in this group were consistent with early stage cholestasis. The pathological score and serum alanine aminotransferase, total bilirubin, and direct bilirubin levels were improved in the PN + mAb group relative to the PN group (P < .05). The PN group showed significantly lower hepatic bsep, mdr1a/mdr1b, mdr2, and mrp2 mRNA expression than the controls (P < .05), but these were significantly increased compared to the PN group (P < .05). Conclusions: Infliximab administered at a single dose of 5 mg/kg body weight ameliorated the progression of PNALD and improved the expression of hepatic ABC transporter genes. Therefore, anti–TNF-α monoclonal antibody may be a beneficial therapy for patients with PNALD.

Background: The American Society for Gastrointestinal Endoscopy (ASGE) has published recommendations in regards to anticoagulant (AC) and antiplatelet (AP) therapy management during endoscopic procedures. So far, no study has assessed either ASGE recommendation compliance during percutaneous endoscopic gastrostomy (PEG) placement or procedure-associated complication rates as related to the observance of these recommendations. The aims of this study were to compare the incidence and type of complications during PEG placement in patients receiving or not receiving AC and/or AP therapy and to determine the compliance with ASGE’s AC and AP management guidelines. Methods: Medical files of patients who underwent PEG placement from January 2004 to December 2008 were reviewed. Clinical and procedure-related data were recorded. Patients were separated into 1 of 2 groups: patients under AP and/or AC therapy prior to PEG placement (n = 51) and a control group of patients (n = 40) not receiving any AP and/or AC treatment at least 6 months prior to the procedure. Results: A total of 91 patients (51 cases) were included. Groups were comparable in demographics and clinical characteristics. No differences in the frequency and type of complications were found between groups. ASGE’s recommendations were not followed in any of these patients. Conclusions: Overall PEG placement complication rate was 13.7%. AP therapy may be safely discontinued closer to the time of endoscopic procedure than the time currently recommended by the ASGE guidelines.

Background: Percutaneous endoscopic gastrostomy (PEG) tube insertion is an uncomfortable procedure that has traditionally required sedation. In some patients, PEG tube insertion can be postponed or is not possible due to the risk of sedation. This article is a retrospective case series of 10 patients who have undergone unsedated peroral PEG tube insertion in the past 4 years at Stafford Hospital in the United Kingdom. Methods: Between 2006 and 2010, 10 patients who were identified by the nutrition team as needing a PEG tube underwent unsedated peroral PEG tube insertion. Patients were given pharyngeal anesthesia (lidocaine 1%), and the PEG tubes were inserted using the push-pull technique and local anesthesia. The procedures were performed without complications. Results: Those patients who were able to respond stated they would be willing to have the procedure performed again using this method. It was acceptable to them and not as unpleasant as they had expected. Conclusions: This case series demonstrates that gastroenterology units without specialized equipment are able to safely insert PEGs in patients who are at increased risk for intravenous sedation.

Acrodermatitis enteropathica is a rare skin disorder of zinc deficiency. This case report describes a 91-year-old female nursing home resident who presented with a skin eruption resembling acrodermatitis enteropathica while receiving adequate enteral nutrition (EN) via a percutaneous gastrostomy tube. A low zinc level of 36 mcg/dL confirmed zinc deficiency, and treatment with oral zinc sulfate 220 mg 3 times a day resulted in rapid resolution of the skin lesions. This case supports the notion of close monitoring of patients on long-term EN for clinical manifestations of zinc deficiency, especially in the presence of an unexplained skin rash. Although micronutrient deficiencies are more prevalent in underdeveloped countries and with patients receiving parenteral nutrition, these deficiencies should be kept in mind for patients in developed countries as well as patients receiving EN.

The purpose of this review is 2-fold. First, it speculates on future scientific work that will have the greatest effect on clinical practice of nutrition care. Second, it discusses the current and future state of the healthcare system, paying special attention to demographic trends and the future of healthcare reform as it will affect nutrition practice.