Gastrointestinal obstruction by solidification of enteral nutrition: a result of impaired digestion in critically ill patients

Introduction:Solidification of enteral nutrition may cause gastrointestinal obstruction, with severe complications. The effect of the composition of enteral nutrition on the tendency of casein to coagulate is increasingly acknowledged and new formulas may prevent solidification. To recognize patients in need of specific enteral nutrition, we have to identify the clinical risk factors for the development of gastrointestinal obstruction by the solidification of enteral nutrition. Materials and methods:The 58 cases summarized in this review were identified through a PubMed search. Results:Critically ill patients have several risk factors, including impaired digestion, and they are treated with medication that interferes with gastrointestinal function. Surgery of the upper gastrointestinal tract is thought to be the most important risk factor, leading to changes in both the anatomical structure and neurohormonal functioning of the gastrointestinal tract, and to altered secretion of digestive enzymes. Conclusions:Awareness of risk factors in critically ill patients may help intensivists and surgeons take appropriate measures to prevent this complication. Critically ill patients with impaired digestion (e.g. after Whipple surgery) should be considered for alternative enteral nutrition formulas with noncoagulating proteins or hydrolyzed proteins

Antioxidative properties of flavonoids

Evidence accumulates that a family of plant compounds, known as flavonoids, can prevent or slow down the progression of cardiovascular diseases, cancer, inflammatory and neurodegenerative diseases. Flavonoids are considered beneficial, this is often attributed to their powerful antioxidant properties. In this role, certain types of flavonoids are considered to be far more powerful than the two most common antioxidants, vitamin C and vitamin E, at preventing cellular damage brought on by free radicals. Interestingly, flavonoids exert those activities not only through direct radical scavenging, but also through regulating nitric oxide, and chelating metals. In addition, flavonoids are thought to facilitate/promote other important biological processes, resulting in modulation of enzymes, a decrease in leukocyte immobilization, inhibition of cell proliferation and angiogenesis, and effects on signaling pathways. The results of in vitro studies have demonstrated that the antioxidative property of flavonoids is unambiguous; however it is still not supported by strong consistent evidence in vivo. Therefore, the antioxidant theory as a mechanism of action of flavonoids is controversial. As a result, flavonoids are hypothesized to exert their activities partly through cell signaling pathways. This review intends to acquaint the reader with different pathways in which flavonoids function or might function. Furthermore, we will provide insight into the beneficial health effects of these substance

Review article: the role of gastrointestinal hormones in the treatment of delayed gastric emptying in critically ill patients

Background The role of diet in inflammatory bowel disease (IBD) is supported by migration studies and increasing incidences in line with Westernisation. Aim To give a complete overview of studies associating habitual diet with the onset or relapses in ulcerative colitis (UC) or Crohn's disease (CD). Methods A structured search in Pubmed, the Cochrane Library and EMBASE was performed using defined key words, including only full text papers in English language. Results Forty-one studies were identified, investigating onset (n = 35), relapses (n = 5) or both (n = 1). Several studies reported high intake of sugar or sugar-containing foods (n = 7 UC, n = 12 CD), and low intake of fruits and/or vegetables (n = 5 UC, n = 10 CD) to be associated with an increased onset risk. However, these findings could not be confirmed by similar or higher numbers of other studies. A possible protective role was found for grain-derived products in CD onset, but results were inconsistent for dietary fibre in UC and CD and grain-derived products in UC. No definite conclusions could be drawn for unsaturated fatty acids (UFA), protein and energy intake due to limited and/or inconsistent results. Six studies reported on diet and relapse risk, of which only two (n = 1 UC, n = 1 CD) had a prospective follow-up. Conclusions The current evidence is not sufficient to draw firm conclusions on the role of specific food components or nutrients in the aetiology of IBD. Furthermore, large prospective studies into the role of habitual diet as a trigger of relapses are needed, to identify new therapeutic or preventive target

Antioxidative properties of flavonoids

Evidence accumulates that a family of plant compounds, known as flavonoids, can prevent or slow down the progression of cardiovascular diseases, cancer, inflammatory and neurodegenerative diseases. Flavonoids are considered beneficial, this is often attributed to their powerful antioxidant properties. In this role, certain types of flavonoids are considered to be far more powerful than the two most common antioxidants, vitamin C and vitamin E, at preventing cellular damage brought on by free radicals. Interestingly, flavonoids exert those activities not only through direct radical scavenging, but also through regulating nitric oxide, and chelating metals. In addition, flavonoids are thought to facilitate/promote other important biological processes, resulting in modulation of enzymes, a decrease in leukocyte immobilization, inhibition of cell proliferation and angiogenesis, and effects on signaling pathways. The results of in vitro studies have demonstrated that the antioxidative property of flavonoids is unambiguous; however it is still not supported by strong consistent evidence in vivo. Therefore, the antioxidant theory as a mechanism of action of flavonoids is controversial. As a result, flavonoids are hypothesized to exert their activities partly through cell signaling pathways. This review intends to acquaint the reader with different pathways in which flavonoids function or might function. Furthermore, we will provide insight into the beneficial health effects of these substance

Preservation of the gut by preoperative carbohydrate loading improves postoperative food intake

Background & aims A carbohydrate (CHO) drink given preoperatively changes the fasted state into a fed state. The ESPEN guidelines for perioperative care include preoperative CHO loading and re-establishment of oral feeding as early as possible after surgery. An intestinal ischaemia reperfusion (IR) animal model was used to investigate whether preoperative CHO loading increases spontaneous postoperative food intake, intestinal barrier function and the catabolic response. Methods Male Wistar rats (n = 65) were subjected to 16 h fasting with ad libitum water and: A) sham laparotomy (Sham fasted, n = 24); B) intestinal ischaemia (IR fasted, n = 27); and C) intestinal ischaemia with preoperatively access to a CHO drink (IR CHO, n = 14). Spontaneous food intake, intestinal barrier function, insulin sensitivity, intestinal motility and plasma amino acids were measured after surgery. Results The IR CHO animals started eating significantly earlier and also ate significantly more than the IR fasted animals. Furthermore, preoperative CHO loading improved the intestinal barrier function, functional enterocyte metabolic mass measured by citrulline and reduced muscle protein catabolism, as indicated by normalization of the biomarker 3-methylhistidine. Conclusions Preoperative CHO loading improves food intake, preserves the GI function and reduces the catabolic response in an IR animal model. These findings suggest that preoperative CHO loading preserves the intestinal function in order to accelerate recovery and food intake. If this effect is caused by overcoming the fasted state or CHO loading remains unclea

Jejunal feeding is followed by a greater rise in plasma cholecystokinin, peptide YY, glucagon-like peptide 1, and glucagon-like peptide 2 concentrations compared with gastric feeding in vivo in humans : A randomized trial

Background: Jejunal feeding is preferred instead of gastric feeding in patients who are intolerant to gastric feeding or at risk of aspiration. However, the impact of gastric feeding compared with that of jejunal feeding on postprandial circulating plasma glucose and amino acid concentrations and the associated endocrine response in vivo in humans remains largely unexplored. Objective: We compared the impact of administering enteral nutrition as either gastric feeding or jejunal feeding on endocrine responses in vivo in humans. Design: In a randomized, crossover study design, 12 healthy young men (mean ± SD age: 21 ± 2 y) received continuous enteral nutrition that contained noncoagulating proteins for 12 h via a nasogastric tube or a nasojejunal tube placed 30-40 cm distal to the ligament of Treitz. Blood samples were collected during the 12-h postprandial period to assess the rise in plasma glucose, amino acid, and gastrointestinal hormone concentrations. Results: No differences were observed in the postprandial rise in circulating plasma amino acid and glucose concentrations between regimens. Jejunal feeding resulted in higher peak plasma insulin concentrations than did gastric feeding (392 ± 53 compared with 326 ± 54 pmol/L, respectively; P <0.05). The postprandial rise in plasma cholecystokinin, peptide YY (PYY), glucagon-like peptide 1 (GLP-1), and glucagon-like peptide 2 (GLP-2) concentrations was greater after jejunal feeding than after gastric feeding, with higher peak concentrations and a greater postprandial incremental AUC for GLP-1 and cholecystokinin (all P <0.05). Plasma ghrelin concentrations did not differ between regimens. Conclusions: Enteral nutrition with gastric or jejunal feeding in healthy young men results in similar postprandial plasma amino acid and glucose concentrations. However, the endocrine response differs substantially, with higher peak plasma cholecystokinin, PYY, GLP-1, and GLP-2 concentrations being attained after jejunal feeding. This effect may result in an improved anabolic response, greater insulin sensitivity, and an improved intestinotropic effect. Nevertheless, it may also lead to delayed gastric emptying.</p

Preservation of the gut by preoperative carbohydrate loading improves postoperative food intake

Background & aims A carbohydrate (CHO) drink given preoperatively changes the fasted state into a fed state. The ESPEN guidelines for perioperative care include preoperative CHO loading and re-establishment of oral feeding as early as possible after surgery. An intestinal ischaemia reperfusion (IR) animal model was used to investigate whether preoperative CHO loading increases spontaneous postoperative food intake, intestinal barrier function and the catabolic response. Methods Male Wistar rats (n = 65) were subjected to 16 h fasting with ad libitum water and: A) sham laparotomy (Sham fasted, n = 24); B) intestinal ischaemia (IR fasted, n = 27); and C) intestinal ischaemia with preoperatively access to a CHO drink (IR CHO, n = 14). Spontaneous food intake, intestinal barrier function, insulin sensitivity, intestinal motility and plasma amino acids were measured after surgery. Results The IR CHO animals started eating significantly earlier and also ate significantly more than the IR fasted animals. Furthermore, preoperative CHO loading improved the intestinal barrier function, functional enterocyte metabolic mass measured by citrulline and reduced muscle protein catabolism, as indicated by normalization of the biomarker 3-methylhistidine. Conclusions Preoperative CHO loading improves food intake, preserves the GI function and reduces the catabolic response in an IR animal model. These findings suggest that preoperative CHO loading preserves the intestinal function in order to accelerate recovery and food intake. If this effect is caused by overcoming the fasted state or CHO loading remains unclea