Short time L-glutamine supplementation of malnourished rats

OBJETIVO: Considerando que em pacientes desnutridos suplementados com L-glutamina, a negatividade do balanço de nitrogênio tende a diminuir, o presente estudo visou determinar se a suplementação com L-glutamina em ratos Wistar desnutridos poderia diminuir a excreção de nitrogênio urinário, melhorar a deposição de nitrogênio em diferentes tecidos e/ou alterar as concentrações plasmáticas de aminoácidos. MÉTODOS: Os animais foram divididos em grupos: 1) desnutrido protéico-energético, 2) desnutrido protéico e 3) nutrido. O nitrogênio urinário e tecidual foi determinado pelo método de Kjeldahl e as concentrações plasmáticas de aminoácido por cromatografia líquida. RESULTADOS: Pesos, nitrogênio urinário e teciduais foram significativamente reduzidos no grupo com desnutrição protéico-energética, não tendo sido encontrada melhora no grupo com suplementação aguda de glutamina. Não foram observadas mudanças nas concentrações plasmáticas de aminoácidos com a suplementação de glutamina. CONCLUSÃO: Não foi possível detectar um efeito positivo da suplementação de glutamina sobre o metabolismo de nitrogênio urinário e tecidual de ratos desnutridos.

Energy expenditure after 2- to 3-hour elective surgical operations

Energy expenditure was measured by indirect calorimetry in 17 adult patients (8 women and 9 men) before surgery, 4 hours immediately after surgery , and 24 hours late after surgery in patients undergoing elective surgery of small-to-medium scope. MATERIAL AND METHODS: The total duration of surgery ranged from 2 to 3 hours. Repeated measures were performed on the same patient, so that each patient was considered to be his/her own control. All patients received a 5 percent dextrose solution (2000 mL/day) throughout the postoperative period. RESULTS: Men showed a reduction in CO2 production during the immediately after surgery period (257 + or - 42 mL/min) compared to before surgery (306 + or - 48 mL/min) and late after surgery (301 + or - 45 mL/min); this reduction was not observed in women. Energy expenditure was also lower in men during immediately after surgery (6.6 kJ/min). None of the other measurements, including substrate oxidation, showed significant differences. CONCLUSION: Therefore, elective surgery itself cannot be considered an important trauma that would result in increased energy expenditure. According to this study, it is not necessary to prescribe an energy supply exceeding basal expenditure during the immediate after-surgery period. The present results suggest that the energy supply prescribed during the postoperative period after elective surgery of small-to-medium scope should not exceed 5-7 kJ/min, so the patient does not receive a carbohydrate overload from energy supplementation