Does glutamine promote benefits for patients with diabetes mellitus scheduled for cardiac surgery?

BACKGROUND: We hypothesised, that perioperative use of N(2)-L-alanyl-L-glutamine confers cardioprotection and improves insulin resistance in diabetic patients with coronary artery disease operated under cardiopulmonary bypass. METHODS: This double-blind, placebo-controlled, randomised study included 64 patients with diabetes mellitus type 2 who were scheduled for on-pump coronary artery bypass graft surgery. The protocol group (32 patients) and the control group (32 patients) glutamine (0.4 g/kg/day of 20% solution of N(2)-L-alanyl-L-glutamine ("Dipeptiven(®)" Fresenius Kabi, Germany)) and placebo (0.9% NaCl), respectively. Perioperative concentration of troponin I in plasma was considered as the primary end-point. Whereas the secondary end-points were insulin resistance, insulin sensitivity, ß-cell function, blood glucose, plasma triglycerides and free fatty acids concentrations. Insulin resistance, insulin sensitivity and ß-cell function were measured using HOMA equation. Thermodilution method was used to measure haemodynamics in all the patients. RESULTS: No differences have been found in perioperative dynamics of troponin I, insulin resistance, insulin sensitivity, ß-cell function, blood glucose, plasma triglycerides free fatty acids concentrations and haemodynamics. CONCLUSION: Our results have failed to confirm the cardioprotective properties and modulatory effect on perioperative insulin resistance that are thought to be attributable to parenteral glutamine administration in dose 0.4 g/kg/day among cardiac patients with DM operated on under CPB.

Prognostic value of nutritional screening tools for patients scheduled for cardiac surgery.

OBJECTIVES: The aim of this study was to assess the prognostic value of different nutritional screening tools in patients undergoing cardiopulmonary bypass, with regard to adverse clinical outcome. METHODS: This prospective cohort study analysed 1193 adult patients who underwent cardiopulmonary bypass. Patients were screened using five nutritional screening tools: Subjective Global Assessment (SGA), Nutritional Risk Screening 2002 (NRS-2002), Malnutrition Universal Screening Tool (MUST), Mini-Nutritional Assessment (MNA) and Short Nutritional Assessment Questionnaire (SNAQ). In-hospital mortality, postoperative complications, length of stay in intensive care unit and length of hospitalization were analysed. Multivariate backward logistic regression analysis was used to assess the independent predictive value of the studied screening tools. RESULTS: In accordance with univariate analysis, malnutrition detected by SNAQ, MUST, NRS-2002 and MNA was associated with postoperative complications (odds ratio [OR] 1.8, 95% confidence interval [95% CI] 1.3-2.4; OR 1.9, 95% CI 1.4-2.6; OR 1.8, 95% CI 1.2-2.9 and OR 1.9, 95% CI 1.4-2.6). Malnutrition detected by MUST, NRS-2002, MNA and SGA was associated with intensive care unit stay >2 days (OR 1.5, 95% CI 1.1-2.1; OR 2.3, 95% CI 1.5-3.7; OR 1.7, 95% CI 1.2-2.2 and OR 2.7, 95% CI 1.6-4.6). Prolonged hospitalization (>20 days) was predicted by SNAQ, MUST and MNA (OR 1.4, 95% CI 1-1.9; OR 1.6, 95% CI 1.2-2.2 and OR 1.6, 95% CI 1.2-2.2). In accordance with multivariate analysis, only MUST and MNA independently predicted postoperative complications (OR 1.6, 95% CI 1.1-2.3 and OR 1.6, 95% CI 1.1-2.2). Other independent factors influencing postoperative complications were well-known logistic EuroSCORE (OR 1.06, 95% CI 1-1.1) and the duration of cardiopulmonary bypass in minutes (OR 1.01, 95% CI 1-1.01). CONCLUSIONS: MUST and MNA both have independent predictive values with regard to postoperative complications. Taking into account simplicity, MUST is preferable for the cardiac surgical population.