Yvon Carpentier

Influence of total parenteral nutrition on fuel utilization in injury and sepsis.

Total parenteral nutrition with hypertonic glucose/AA solutions given to eighteen nutritionally depleted patients resulted in a rise in the respiratory quotient (RQ) from 0.83 to 1.05 (p less than .001), while oxygen consumption (VO2) increased only 3%. Excess glucose in depleted patients was converted to fat as evidenced by an RQ greater than 1.0. Administration of a similar glucose load to fourteen hypermetabolic patients (injury/infection) resulted in a rise in RQ from 0.76 to 0.90 while VO2 increased 29% (p less than .001) In hypermetabolic patients, even with administration of glucose in quantities above energy expenditure, there was still ongoing utilization of fat for energy, resulting in a RQ significantly less than 1.0. Excess glucose under these circumstances is apparently converted to glycogen while fat stores are utilized to partially meet energy needs. Septic and injuried man seems to preferentially utilize endogenous fat as an energy source. Administration of a large glucose load to hypermetabolic patients does not totally suppress the net fat oxidation as it does in depleted patients. Rather there is an increase in VO2, continuing oxidation of fat and apparently an increase in the conversion of glucose to glycogen.

Muscle and plasma amino acids following injury. Influence of intercurrent infection.

The present study was undertaken to determine intracellular amino acid patterns in patients with multiple trauma, whether or not complicated by sepsis and during convalescence. A percutaneous muscle biopsy was performed three to four days following major accidental injury in ten patients and analyzed for muscle free amino acids. Venous blood was drawn at the time of the biopsy and analyzed for plasma free amino acids. Five patients developed sepsis and a repeat biopsy was performed on days 8 to 11. In five of the patients a biopsy was performed during the late convalescent period (anabolic phase). A marked depletion of nonessential amino acids in muscle occurred in both injury and sepsis due to a decrease (50%) in glutamine, which was equally marked in both states. The essential amino acids in muscle increased in injury. During sepsis, a further increase was observed with a return toward normal in the convalescent period. In injury, the most marked rise was in the branched-chain amino acids, phenylalanine, tryosine and methionine. With sepsis, a further rise in muscle branched-chain amino acids, phenylalanine and tryosine occurred, while plasma levels remain unchanged. During convalescence, muscle glutamine, arginine, histidine and plasma branched-chain amino acids were below normal, whereas muscle phenylalanine and methionine were elevated. The muscle free amino acid pattern observed after major trauma was essentially the same as earlier described following elective operation. This suggests a common response of intracellular amino acids irrespective of the degree of injury, and may indicate that the pump settings which regulate amino acid transport follow the “all or none” rule. The high intracellular levels of branched-chain amino acids in sepsis suggest that the energy deficit of this state is due to an impairment of substrate use rather than intracellular availability. The high concentrations of the aromatic amino acids and methionine may be due to altered liver function. During the late convalescent period (anabolic phase) the low levels of certain key amino acids suggests inadequate nutrition. The difficulties in nourishing the injured or septic patient are well recognized. The period following these catabolic states may be an important period for the application of an optimal, aggressive nutritional regimen.

Prognosis of patients with nonmalignant chronic intestinal failure receiving long-term home parenteral nutrition

BACKGROUND/AIMS Long-term survival of patients with intestinal failure requiring home parenteral nutrition (HPN) has been only partly shown. Therefore, we described the survival of these patients and explored prognosis factors. METHODS Two hundred seventeen noncancer non-acquired immunodeficiency syndrome adult patients presenting with chronic intestinal failure enrolled from January 1980 to December 1989 in approved HPN programs in Belgium and France; prognosis factors of survival were explored using multivariate analysis. Data were updated in March 1991; not one of the patients was lost to follow-up. RESULTS Seventy-three patients died during the survey, and the mortality rate related to HPN complications accounted for 11% of deaths. Probabilities of survival at 1, 3, and 5 years were 91%, 70%, and 62%, respectively. Three independent variables were associated with a decreased risk of death: age of patients younger than 40 years, start of HPN after 1987, and absence of chronic intestinal obstruction. In patients younger than 60 years of age included after 1983 with a very short bowel, who could represent suitable candidates for small bowel transplantation, the 2-year survival rate was 90%, a prognosis that compared favorably with recent reports of survival after small bowel transplantation. CONCLUSIONS HPN prognosis compares favorably with recent reports of survival after small bowel transplantation.

Free fatty acid mobilization and oxidation during total parenteral nutrition in trauma and infection.

Free fatty acid (FFA) metabolism was studied in 18 traumatized and/or septic patients. Each patient was studied while receiving 5% dextrose (D5W) and after 4 to 7 days of total parenteral nutrition (TPN). Nonprotein energy during TPN was given either entirely as glucose (Glucose System) or as equal portions of intravenous fat and glucose (Lipid System). Plasma FFA concentrations were in the normal range on D5W and decreased markedly with TPN. FFA turnover was higher than normal on D5W and did not decrease significantly with TPN. The poor correlation between these two variables emphasizes the need to perform kinetic studies to characterize FFA metabolism in trauma and sepsis. Plasma FFA oxidation and net whole body fat oxidation measured by indirect calorimetry were in the normal range on D5W, 35 and 82%, respectively, of resting energy expenditure (REE). With a glucose intake averaging 108% of REE, plasma FFA oxidation and net fat oxidation decreased to 17 and 13%, respectively, of REE. Nonprotein RQ increased only to 0.94 despite administration of glucose in excess of REE, indicating an abnormal persistence of fat oxidation. During D5W administration, plasma FFA accounted for less than one half of total fat oxidation, indicating that unlabeled fat, such as tissue or plasma triglycerides not in rapid equilibrium with plasma FFA, accounted for the bulk of fat oxidation. Glucagon concentrations which were high on D5W did not decrease significantly with TPN. Insulin concentrations were normal on D5W and increased in response to TPN. The abnormal hormonal milieu may account for much of the abnormal fat metabolism. Administration of large amounts of glucose decreased FFA oxidation much more than FFA mobilization. Thus, the infused glucose acts to increase the rate of “futile cycling” of FFA in these acutely ill patients.

Management of nutrition in European intensive care units : results of a questionnaire

Objective: To describe the practical aspects of nutritional management in intensive care units (ICUs). Design: A 49-item questionnaire was sent to the physician members of the European Society for Intensive Care Medicine. The issues addressed included: medical environment, assessment of nutritional status and current practice for enteral and parenteral nutrition. Setting: 1608 questionnaires were sent in 35 European countries. Analysis: The answers were pooled and stratified by country. Results: 271 questionnaires were answered (response rate 17 %). Assessment of nutritional status was generally based on clinical (99 %) and biochemical (82 %) parameters rather than on functional (24 %), anthropometric (23 %), immunological (18 %) or questionnaire-based (11 %) data. Two thirds of 2774 patients hospitalised in the corresponding ICUs at the time the questionnaire was answered were receiving nutritional support; 58 % of those were fed by the enteral route, 23 % by the parenteral route and 19 % by combined enteral and parenteral. The preferred modality was enteral nutrition, instituted before the 48th h after admission, at a rate based on estimated caloric requirements. Specific and modified solutions were rarely used. Parenteral nutrition was less commonly used than enteral, although the practices differed between countries. It was mainly administered as hospital-made all-in-one solutions, at a rate based on calculated caloric requirements. Conclusions: European intensivists are concerned by the nutritional management of their patients. The use of nutritional support is common, essentially as early enteral feeding.

Changes in the concentration and composition of plasma lipoproteins during the acute phase response.

The acute phase reactions, associated with injury, inflammation, or sepsis, markedly affect the concentration and composition of plasma lipids and lipoproteins. Hepatic production of triglycerides and very low density lipoprotein formation are increased, but do not necessarily result in high plasma triglyceride levels. In contrast, all conditions lower plasma cholesterol by decreasing its content in both low-density and high-density lipoproteins. In addition, substantial changes in protein and lipid composition of lipoproteins are observed that may redefine the function of these particles, but also increase their atherogenic and inflammatory properties.

Effects of hypercaloric glucose infusion on lipid metabolism in injury and sepsis.

UNLABELLED Lipolysis was studied by measuring glycerol turnover (GTO) in injured and infected patients. GTO was elevated two to three times the normal values in five injured and four infected patients during D5W infusion. No correlation was found between GTO and plasma glycerol concentration in the two patient groups. GTO showed similar levels when measured during TPN in five injured and three infected patients. During TPN, plasma FFA levels remained unchanged in injured but decreased by 48% in septic patients. B-OH butyrate concentrations were high during D5W and dropped in both groups during TPN. Norepinephrine urinary output was high in both groups during D5W and TPN. CONCLUSIONS 1) GTO was elevated two to three times the normal range in injury and infection; plasma glycerol concentration was not related to GTO. 2) In face of high catecholamine output, the insulin response to TPN did not inhibit TG breakdown but did decrease plasma ketone body concentrations.

Plasma lipid and plasma lipoprotein concentrations in low birth weight infants given parenteral nutrition with twenty or ten percent lipid emulsion.

Because 10% and 20% intravenously administered lipid emulsions (intralipid preparations) differ in their phospholipid/triglyceride ratio (0.12 and 0.06, respectively), 28 low birth weight infants requiring parenteral nutrition for at least 1 week were selected at random to receive either emulsion to determine the effects on plasma lipids and lipoproteins. Triglyceride intake was progressively increased to reach 2 gm/kg per day between days 4 and 7. During that period, all plasma lipids in samples taken 6 hours after infusion were higher in the 10% intralipid group. In comparison with day 0 values, triglyceride concentrations decreased (63 +/- 7 to 45 +/- 4 mg/dl; p less than 0.05) in the 20% group. Cholesterol levels increased in both groups, but the rise was more than twofold higher in the 10% group. Phospholipid increase was approximately 25% in the 20% group but more than 125% in patients receiving the 10% emulsion (p less than 0.005). The changes in plasma cholesterol and phospholipid levels were almost entirely in low-density lipoproteins. After 7 days, eight infants from each group were given the alternate emulsion, which resulted in a reversal of lipid patterns in each patient. We conclude that the higher phospholipid intake in 10% than in 20% intralipid is associated with higher plasma triglyceride concentrations and leads to accumulation of cholesterol and phospholipids in low-density lipoproteins. Emulsions with lower phospholipid content may be preferable for low birth weight infants and perhaps other patient populations with impaired removal of parenteral fat emulsions.

Management of familial hypercholesterolemia in children and young adults: Consensus paper developed by a panel of lipidologists, cardiologists, paediatricians, nutritionists, gastroenterologists, general practitioners and a patient organization

UNLABELLED Since heterozygous familial hypercholesterolemia (HeFH) is a disease that exposes the individual from birth onwards to severe hypercholesterolemia with the development of early cardiovascular disease, a clear consensus on the management of this disease in young patients is necessary. In Belgium, a panel of paediatricians, specialists in (adult) lipid management, general practitioners and representatives of the FH patient organization agreed on the following common recommendations. 1. Screening for HeFH should be performed only in children older than 2 years when HeFH has been identified or is suspected (based on a genetic test or clinical criteria) in one parent.2. The diagnostic procedure includes, as a first step, the establishment of a clear diagnosis of HeFH in one of the parents. If this precondition is satisfied, a low-density-lipoprotein cholesterol (LDL-C) levelabove 3.5 mmol/L (135 mg/dL) in the suspected child is predictive for differentiating affected from non-affected children. 3. A low saturated fat and low cholesterol diet should be started after 2 years, under the supervision of a dietician or nutritionist.4. The pharmacological treatment, using statins as first line drugs, should usually be started after 10 years if LDL-C levels remain above 5 mmol/L (190 mg/dL), or above 4 mmol/L (160 mg/dL) in the presence of a causative mutation, a family history of early cardiovascular disease or severe risk factors. The objective is to reduce LDL-C by at least 30% between 10 and 14 years and, thereafter, to reach LDL-C levels of less than 3.4 mmol/L (130 mg/dL). CONCLUSION The aim of this consensus statement is to achieve more consistent management in the identification and treatment of children with HeFH in Belgium.

Colonic mucosal atrophy induced by a liquid elemental diet in rats

The weight, the total crypt cell population, and the proliferation parameters of the colon were estimated in rats during a 4-week administration of a liquid elemental diet (Vivonex® standard). Both mitotic and DNA synthesis activity were decreased (P<0.01) in the colonic mucosa during the administration of the diet. The weight of the colon was electively decreased (P<0.01) from the first week of the treatment. After four weeks, a 75% decrease in the cell population of mucosal glands was observed. This showed that considerable atrophy of the colonic mucosa occurred under the effect of feeding the elemental diet. This atrophy was probably mediated by a reduction in the proliferative activity of the stem cells in the mucosal glands.