Prognostic value of energy expenditure and respiratory quotient measuring in patients with liver cirrhosis.

BACKGROUND & AIMS: Resting energy expenditure (REE) and respiratory quotient (RQ) as measured by indirect calorimetry (IC) may correlate with muscle mass and represent prognostic indicators in treating patients with liver cirrhosis. We aimed to assess the correlation of IC-measured REE and RQ with skeletal muscle mass (SM), mortality, and REE values as estimated by Harris-Benedict, European guidelines (EG), and Brazilian guidelines-DITEN (BG) equations in patients with liver cirrhosis. METHODS: In this prospectively designed study, REE was measured in 126 male patients with liver cirrhosis by IC and predicted by Harris-Benedict, EG (35 kcal/kg current weight), and BG (30 kcal/kg current weight) guidelines. Measurements were obtained at the time of admission to the study. Body composition was determined by whole-body dual-energy X-ray absorptiometry. The association between REE and 3-year survival was investigated. RESULTS: Cirrhosis etiology was classified as alcohol related (59.0%), viral (20.1%), cryptogenic (11.8%), or other (9.0%). Mean Child-Pugh and MELD indexes were 8.30 ± 2.0 and 14.38 ± 6.12, respectively. RQ showed a moderate correlation with SM (r = 0.64), while IC-measured REE was inversely associated with mortality (multivariate Cox Regression, HR = 0.88, 95% CI: 0.78; 1, p = 0.04). Among the predictive equations for REE, only Harris-Benedict yielded values close to the IC, with a positive Pearson correlation (r = 0.77), excellent accuracy (Cb = 0.98), and positive Lin's concordance correlation (CCC = 0.75). However, a large standard deviation was observed; HB-measured REE did not correlate with mortality. CONCLUSIONS: RQ and REE, as measured by IC, may be valuable tools for evaluating the severity of cirrhosis, by reflecting SM and predicting mortality, respectively. The predictive equations for REE included in this study cannot replace IC for this purpose. REGISTERED AT: www.clinicalTrials.gov (NCT02421848).

Parenteral lipid emulsions and phagocytic systems.

Lipid emulsions (LE) for parenteral use are complex emulsions containing fatty acids, glycerol, phospholipids and tocopherol in variable amounts and concentrations. In clinical practice, LE have been employed for more than 30 years. Fatty acids may have different impacts on phagocytic cells according to their structure. Experimental and clinical studies have consistently shown that LE modify monocyte/macrophage and polymorphonuclear phagocytosis. The inhibitory effect of LE on the functional activity of the phagocytic system, although still clinically controversial, may have a harmful impact because total parenteral nutrition with lipids may be recommended in hypercatabolic conditions where inflammation and infection are present. LE based on triglycerides containing long chain fatty acids (termed long chain triglycerides or LCT) are the main parenteral fat source and are typically rich in n-6 polyunsaturated fatty acids. They may have adverse effects on the immune system, especially when given in high doses over a short period of time. However when administered properly they can be used safely. LE containing medium chain triglycerides (MCT) may have some advantages because of their positive effects on polymorphonuclear cells, macrophages, and cytokine production, particularly in critically ill or immunocompromised patients. New parenteral LE containing n-3 polyunsaturated fatty acids or monounsaturated olive oil are already available in Europe. Judicious use of these new LE is mandatory especially relating on their potential impact on the immune system. New experimental and clinical studies are required to further establish the role of LE in clinical nutrition.

Impact of parenteral n-3 fatty acids on experimental acute colitis.

The present study was undertaken to investigate the effects of parenteral lipid emulsions (LE) enriched with n-3 fatty acids (n-3 FA) in experimental acute colitis. Seventy-four adult male Wistar rats were randomized into six groups, five of which had acetic acid-induced colitis. The animals received a fat-free diet and water ad libitum in individual metabolic cages. By a central venous catheter, saline was infused (0.5 ml/h) into the control groups CS (without colitis) and CC (with colitis), while the test groups received specific LE for 7 days. The n-3/n-6 FA ratio and the lipidic compositions regarding long chain (LCT) and medium chain (MCT) triglycerides were: group L--1:7.7 (LCT, n = 12), M--1:7.0 (MCT and LCT, n = 12), LW-3--1:4.5 (LCT plus n-3 FA, n = 12) and MW-3--1:3.0 (MCT and LCT plus n-3 FA, n = 13). The frequency of diarrhea, oral intake/body weight ratio, intestinal alterations, macrophage cellularity were evaluated and colonic concentrations of leukotrienes (LTB4, LTC4), prostaglandins (PGE2) and thromboxanes (TXB2) were measured. Groups M, MW-3 and LW-3 had less diarrhea than the CC group (P<0.05). Average oral intake/body weight ratio in MW-3 animals was comparable to the CS and better than the CC group. n-3 FA treated rats (LW-3 and MW-3) presented less intestinal inflammatory alterations than CC rats. Mucosal ulcer formation in MW-3 group did not differ from CS rats. M and MW-3 rats had less macrophages in the colon than the CC group. Compared with CC group, lower concentrations of LTB4 in the CS, LW-3 and MW-3 groups; of PGE2 in the CS, M and MW-3 groups; and of TXB2 in the CS and MW-3 groups were found. Mean concentrations of LTC4 did not differ among the groups. Thus, a LCT-containing LE with a low n-3-n-6 ratio does not modify inflammatory colitis manifestations; LE with a high n-3-n-6 ratio reduces diarrhea, preserves oral intake-weight ratio, attenuates morphological consequences and decreases colonic concentrations of inflammatory mediators; MCT/LCT-containing LE with 1:3 n-3-n-6 ratio exerts the most profound beneficial impact on the inflammatory response.