Accuracy of the BAR score in the prediction of survival after liver transplantation.

INTRODUCTION AND AIM: The Balance of Risk (BAR) Score, a simple scoring system that combines six independent donor and recipient variables to predict outcome after liver transplantation (LT), was validated in a large U.S./European cohort of patients. This study aims to assess the performance of the BAR score to predict survival after liver transplantation and determine the factors associated with short and long-term survival in Latin-American patients. MATERIAL AND METHODS: A retrospective cohort study was performed in 194 patients [112 (55.4%) males; mean age 52±14 years] who underwent 202 LT during the period 2003-2015. Demographic, clinical, pathological and surgical variables, as well as mortality and survival rates, were analyzed. The BAR score was investigated through a receiver operating characteristics (ROC) curve with the calculation of the area under the curve (AUC) to evaluate the predictive score power for 3-month, 1 and 5-year mortality in a matched donor-recipient cohort. Youden index was calculated to identify optimal cutoff points. RESULTS: The AUC of BAR score in predicting 3-month, 1-year and 5-year mortality were 0.755 (CI95% 0.689-0.812), 0.702 (CI95% 0.634-0.764) and 0.610 (CI95% 0.539-0.678) respectively. The best cut-off point was a BAR score ≥15 points. In the multivariate analysis BAR score <15 was associated with higher survival rates at 3 months and 1 and 5-years. CONCLUSIONS: BAR score <15 points is an independent predictor of better short and long-term survival in Latin-American patients undergoing LT. The BAR scoring system has an adequate diagnostic capacity allowing to predict 3 and 12-month mortality.

¿Influye el medio de preservación del injerto en los resultados y costos del trasplante hepático de donante fallecido?: Comparación de dos soluciones de preservación / Outcomes using two preservation solutions (UW/HTK) in liver transplantation from brain death donors

Background: Preservation solutions are critical for organ transplantation. In liver transplant (LT), the solution developed by the University Of Wisconsin (UW) is the gold-standard to perfuse deceased brain death donor (DBD) grafts. Histidine-Tryptophan-Ketoglutarate (HTK), formerly a cardioplegic infusion, has been also used in solid organ transplantation. Aim: To compare the outcomes of LT in our center using either HTK or UW solution. Patients and Methods: Retrospective study including 93 LT DBD liver grafts in 89 patients transplanted between March 1994 and July 2010. Forty-eight grafts were preserved with UW and 45 with HTK. Donor and recipient demographics, total infused volume, cold ischemia time, post-reperfusion biopsy, liver function tests, incidence of biliary complications, acute rejection and 12-month graft and patient survival were assessed. Preservation solution costs per liver graft were also recorded. Results: Donor and recipient demographics were similar. When comparing UW and HTK, no differences were observed in cold ischemia time (9.6 ± 3 and 8.7 ± 2 h respectively, p = 0.23), biliary complications, the incidence of acute rejection, primary or delayed graft dysfunction. Histology on post-reperfusion biopsies revealed no differences between groups. The infused volume was significantly higher with HTK than with UW (9 (5-16) and 6 (3-11) l, p < 0.001). The cost per procurement was remarkably lower using HTK. Conclusions: Perfusion of DBD liver grafts with HTK is clinically equivalent to UW, with a significant cost reduction.

[Outcomes using two preservation solutions (UW/HTK) in liver transplantation from brain death donors]. / ¿Influye el medio de preservación del injerto en los resultados y costos del trasplante hepático de donante fallecido?: Comparación de dos soluciones de preservación.

BACKGROUND: Preservation solutions are critical for organ transplantation. In liver transplant (LT), the solution developed by the University Of Wisconsin (UW) is the gold-standard to perfuse deceased brain death donor (DBD) grafts. Histidine-Tryptophan-Ketoglutarate (HTK), formerly a cardioplegic infusion, has been also used in solid organ transplantation. AIM: To compare the outcomes of LT in our center using either HTK or UW solution. PATIENTS AND METHODS: Retrospective study including 93 LT DBD liver grafts in 89 patients transplanted between March 1994 and July 2010. Forty-eight grafts were preserved with UW and 45 with HTK. Donor and recipient demographics, total infused volume, cold ischemia time, post-reperfusion biopsy, liver function tests, incidence of biliary complications, acute rejection and 12-month graft and patient survival were assessed. Preservation solution costs per liver graft were also recorded. RESULTS: Donor and recipient demographics were similar. When comparing UW and HTK, no differences were observed in cold ischemia time (9.6 ± 3 and 8.7 ± 2 h respectively, p = 0.23), biliary complications, the incidence of acute rejection, primary or delayed graft dysfunction. Histology on post-reperfusion biopsies revealed no differences between groups. The infused volume was significantly higher with HTK than with UW (9 (5-16) and 6 (3-11) l, p < 0.001). The cost per procurement was remarkably lower using HTK. CONCLUSIONS: Perfusion of DBD liver grafts with HTK is clinically equivalent to UW, with a significant cost reduction.

Decrease in oxidative stress through supplementation of vitamins C and E is associated with a reduction in blood pressure in patients with essential hypertension.

Oxidative stress has been associated with mechanisms of EH (essential hypertension). The aim of the present study was to test the hypothesis that the antioxidant properties of vitamins C and E are associated with a decrease in BP (blood pressure) in patients with EH. A randomized double-blind placebo-controlled clinical trial was conducted in 110 men with grade 1 EH (35-60 years of age without obesity, dyslipidaemia and diabetes mellitus, non-smokers, not undergoing vigorous physical exercise, without the use of any medication and/or high consumption of fruit and vegetables). Participants were randomly assigned to receive either vitamins C+E [vitamin C (1 g/day) plus vitamin E (400 international units/day)] or placebo for 8 weeks. Measurements included 24 h ambulatory BP and blood analysis of oxidative-stress-related parameters in erythrocytes (GSH/GSSH ratio, antioxidant enzymes and malondialdehyde) and plasma [FRAP (ferric reducing ability of plasma)], and levels of 8-isoprostane, vitamins C and E were measured at baseline and after treatment. Following administration of vitamins C+E, patients with EH had significantly lower systolic BP, diastolic BP and mean arterial BP and higher erythrocyte and serum antioxidant capacity compared with either placebo-treated patients with EH or the patients with EH at baseline prior to treatment. BP correlated positively with plasma 8-isoprostane levels and negatively with plasma FRAP levels in the vitamins C+E- and placebo-treated groups. In conclusion, the present study supports the view that oxidative stress is involved in the pathogenesis of EH, and that enhancement of antioxidant status by supplementation with vitamins C and E in patients with EH is associated with lower BP. This suggests intervention with antioxidants as an adjunct therapy for hypertension.

Relationship between (Na + K)-ATPase activity, lipid peroxidation and fatty acid profile in erythrocytes of hypertensive and normotensive subjects.

Oxidative stress may play a role in the pathogenic mechanism of essential hypertension. Lipid peroxidation can alter the cellular structure of membrane-bound enzymes by changing the membrane phospholipids fatty acids composition. We investigated the relationship between (Na + K)-ATPase activity, lipid peroxidation, and erythrocyte fatty acid composition in essential hypertension. The study included 40 essential hypertensive and 49 healthy normotensive men (ages 35-60 years). Exclusion criteria were obesity, dyslipidemia, diabetes mellitus, smoking, and any current medication. Patients underwent 24-h ambulatory blood pressure monitoring and blood sampling. Lipid peroxidation was measured in the plasma and erythrocytes as 8-isoprostane or malondialdehyde (MDA), respectively. Antioxidant capacity was measured as ferric reducing ability of plasma (FRAP) in the plasma and as reduced/oxidized glutathione (GSH/GSSG ratio) in erythrocytes. (Na + K)-ATPase activity and fatty acids were determined in erythrocyte membranes. Hypertensives had higher levels of plasma 8-isoprostane, erythrocyte MDA, and relative percentage of saturated membrane fatty acids, but lower plasma FRAP levels, erythrocyte GSH/GSSG ratio, (Na + K)-ATPase activity and relative percentage of unsaturated membrane fatty acids, compared with normotensives. Day-time systolic and diastolic blood pressures correlated positively with lipid peroxidation parameters, but negatively with (Na + K)-ATPase activity. These findings suggest that the modulation of (Na + K)-ATPase activity may be associated with changes in the fatty acid composition induced by oxidative stress and provide evidence of a role for this enzyme in the pathophysiology of essential hypertension.

Relationship between oxidative stress and essential hypertension.

This study investigated the association of blood pressure with blood oxidative stress-related parameters in normotensive and hypertensive subjects. A cross-sectional design was applied to 31 hypertensive patients and 35 healthy normotensive subjects. All subjects were men between the ages of 35 and 60 years. Exclusion criteria were obesity, dyslipidemia, diabetes mellitus, smoking and current use of any medication. All patients underwent 24-h ambulatory blood pressure monitoring and sampling of blood and urine. Antioxidant enzymes activity, reduced/oxidized glutathione ratio (GSH/GSSG), and lipid peroxidation (malondialdehyde) were determined in erythrocytes. Parameters measured in the plasma of test subjects were plasma antioxidant status, lipid peroxidation (8-isoprostane), plasma vitamin C and E, and the blood pressure modulators renin, aldosterone, endothelin-1 and homocysteine. Daytime systolic and diastolic blood pressures of hypertensives were negatively correlated with plasma antioxidant capacity (r=-0.46, p<0.009 and r=-0.48, p<0.007), plasma vitamin C levels (r=-0.53, p<0.003 and r=-0.44, p<0.02), erythrocyte activity of antioxidant enzymes, and erythrocyte GSH/GSSG ratio, with hypertensives showing higher levels of oxidative stress. Blood pressures showed a positive correlation with both plasma and urine 8-isoprostane. Neither plasma vitamin E nor the assessed blood pressure modulator levels showed significant differences between the groups or correlation with blood pressures. These findings demonstrate a strong association between blood pressure and some oxidative stress-related parameters and suggest a possible role of oxidative stress in the pathophysiology of essential hypertension.