Serum uric acid, creatinine, and the assessment of antioxidant capacity in critical illness

No Abstract - The letter addresses the issue of low plasma urate as a marker of impaired antioxidant capacity in critical illness

Parenteral Nutrition in Liver Resection

Albeit a very large number of experiments have assessed the impact of various substrates on liver regeneration after partial hepatectomy, a limited number of clinical studies have evaluated artificial nutrition in liver resection patients. This is a peculiar topic because many patients do not need artificial nutrition, while several patients need it because of malnutrition and/or prolonged inability to feeding caused by complications. The optimal nutritional regimen to support liver regeneration, within other postoperative problems or complications, is not yet exactly defined. This short review addresses relevant aspects and potential developments in the issue of postoperative parenteral nutrition after liver resection

Patterns of correlation of plasma ceruloplasmin in sepsis

Background. In sepsis, plasma ceruloplasmin (Cp, mg/L) is known to increase as part of the acute phase response. However, there is poor knowledge of the patterns of increase and correlation with changes in other biochemical variables, and our study has been performed to investigate this aspect. Materials and methods. A total of 213 simultaneous measurements of Cp and other acute phase proteins, biochemical variables, and amino acids were performed on nine patients with severe sepsis, and processed by regression analysis. Results. Mean Cp was 478 +/- 119 mg/L (median 488, range 242-784). Significant direct correlations between Cp and C-reactive protein, alpha-1-antitrypsin and alpha-2-macroglobulin (P < 0.001 for all) were all simultaneously influenced by the level of alkaline phosphatase, which was an independent determinant of increased Cp (P < 0.001). Cp increased further with decreasing plasma pH and increasing triglyceride, taurine levels, and distance from the onset of sepsis (P < 0.001 for all). The maximum increases in Cp were associated with the presence of cholestasis, increasing triglyceride levels, and metabolic acidosis. With regard to septic liver dysfunction, while signs of cholestasis were mostly reflected in greater increases in Cp, increasing bilirubin in the presence of normal alkaline phosphatase was mostly correlated with abnormal increases in cyst(e)ine, cystathionine, and tyrosine levels. Conclusions. These data characterize the patterns of correlation of Cp within the biochemical abnormalities of sepsis, and may provide new insights into the pathophysiology of septic hepatobiliary dysfunction

Co-variation of plasma sodium, taurine and other amino acid levels in critical illness

This study investigates the relationship between changes in plasma sodium and changes in amino acid levels in a patient with post-traumatic sepsis and prolonged critical illness. Ninety-two consecutive measurements were performed at regular intervals over a period of many weeks; these consisted in the determination of full amino-acidograms, plasma sodium and complementary variables. A unique, highly significant inverse correlation between taurine and plasma sodium was found (r(2) = 0.48, p < 0.001). All other amino acids were unrelated, or much more weakly related, to sodium. Taurine was also strongly and directly related to phosphoethanolamine, glutamate and aspartate. Changes in sodium and in levels of these amino acids explained up to 86% of the variability of taurine. Besides, levels of these amino acids maintained a high degree of co-variation, remaining reciprocally related one to each other, directly, with r(2) ranging between 0.33 and 0.59 (p < 0.001 for all). There were similar findings for beta-alanine, which however was measured inconsistently. These data provide gross clinical evidence of a specific link binding plasma sodium and taurine levels, and may be consistent with occurrence of opposite and interdependent shifts of sodium and taurine between intravascular and extravascular space, to maintain osmoregulation. Co-variation of taurine with the other amino acids may be related to the same phenomenon, and/or to similarities in transport systems and chemical structure, or true metabolic interactions

Specific effects of olive oil-based lipid emulsions in critical care. A preliminary report

The article addresses the impact of predominantly olive oil-containing parenteral fat emulsions, in critically ill patients, on cholesterol precursors (squalene) and on other metabolites, with no impact on indices of lipid peroxidation

Hypotransferrinemia and changes in plasma lipid and metabolic patterns in sepsis

This study was performed to obtain a characterization of the changes in plasma transferrin (Tf, g/L) in sepsis. More than four hundred determinations of Tf, and of a large series of simultaneously collected blood and hemodynamic variables, were obtained in 17 patients with post-traumatic sepsis. Tf during sepsis was consistently low (mean +/- A SD = 1.46 +/- A 0.46) however fluctuated markedly according to changes in metabolic and hemodynamic patterns. Regression analysis showed that decreases in Tf were simultaneously correlated with the plasma lipid pattern (in particular with decreasing cholesterol and increasing triglycerides), with decreases in albumin and peripheral O(2) extraction, and with increasing cardiac index (p < 0.001 for all). Decreases in Tf were moderated by increasing the parenteral amino acid dose (p < 0.001). Combinations of these variables in multiple regressions explained nearly 80% of the variability of Tf. There were no similar correlations for other acute phase proteins except ceruloplasmin, which showed opposite changes compared to those of Tf. These results show that within the hypotransferrinemia which characterizes sepsis, Tf may oscillate remaining strongly correlated with changes in metabolic and hemodynamic patterns, which may account for nearly 80% of the variability of Tf

Use of unconventional lipid substrates in parenteral nutrition [in Italian]

In addition to the classic soybean oil fat emulsion, developed more than 40 years ago and still widely used, emulsions with other lipid substrates are available today for parenteral nutrition; these substrates implement the benefits offered by soybean oil when mixed with it in given proportions. Soybean oil triglycerides are rich in linoleic acid, a long chain omega-6 polyunsaturated fatty acid, which is essential and is an indispensable component of parenteral nutrition. However, very high doses of omega-6 polyunsaturated fatty acids should be avoided, particularly in some critical illnesses. Medium chain triglycerides, long well known to nutritionists and dietitians for their easy intestinal absorption, have become available in parenteral nutrition emulsions in a mixture with soybean oil. Medium chain triglycerides are completely and readily used for energy production and do not interfere significantly in the production of inflammatory mediators, in the composition of cell membranes and in body organ and system functions. Omega-3 polyunsaturated fatty acids, essential fatty acids derived from fish oil, permeate cell structure and affect cell activity with different mechanisms, playing also an important role in the modulation of inflammatory processes. Omega-3 emulsions in parenteral nutrition are currently added as a supplement to other fat emulsions. Knowledge of these "non-conventional" fat emulsions is being continuously improved by investigative work and clinical experience

Hypocholesterolemia in clinically serious conditions

Background: Cholesterol is an essential component of cell membranes, precursor of steroids, biliary acids and other components of serious importance in live organism. Cholesterol synthesis is a complicated and energy-demanding process. Real daily need of cholesterol and mechanisms of decline cholesterol levels in critical ill are unknown. During stressful situations a significant hypocholesterolaemia may be found. Hypocholesterolemia has been known for a number of years to be a significant prognostic indicator of increased morbidity and mortality connected with a whole spectrum of pathological conditions. The aim of article is the elucidation of the role and importance of hypocholesterolaemia during the intensive care. Methods and Results: We examined studies that are engaged in problems of hypocholesterolemia in critically ill. Very low levels of total as well as LDL cholesterol are most frequently found in serious polytrauma, after extensive surgery, in serious infections, in protracted hypovolemic shock. It is still not clear whether hypocholesterolemia refl ects only a serious metabolic disorder, which results from a life-threatening condition, or whether it has an active role in evolution and outcome. Conclusions: Hypocholesterolemia is commonly observed in critically ill patients. Nevertheless, it is not known whether it is a secondary manifestation of disease, or whether it actively contributes to deterioration of the disease. Although the contribution of hypocholesterolemia to mortality is modest compared with known risk factors such as increased severity of illness and the development of nosocomial infection, low serum lipid concentrations represent a potential therapeutic target in sepsis