 T-Test or Mann-Whitney test will be used for the variables comparison between the groups infectionsno infections, sepsisno sepsis, survivorsnon survivors. ROC curves Receiver Operating Characteristics will be made to evaluate the discriminatory power of blood glucose levels, SD, MAGE, CV and GLI for the infections development, sepsis and outcome. Binary logistic regression will be applicated for analyzing the correlation between glycemic variability, infections development, sepsis and outcome, including APACHE II, SOFA, age, sex, presence of diabetes, blood lactates at the admission and mean value, insulin administration, type of nutrition, mechanical ventilation and length of ICU stay as covariates. 