The relationship between the distinction of nutritional supply to critically ill patients in different divisions and clinical outcomes

Background and objectives: The strategy of nutritional intervention was correlated with clinical outcomes in critically ill patients. Previous studies had found that not all critical patients improved the outcome after increasing caloric intake. In the acute phase of critical ill, the critical patients produced energy by catabolism to supply the energy expenditure. The debt of energy was the amount of energy supply. However, the difference of catabolism was existed between the different diseases. The purpose of this study was to retrospectively investigate whether the pattern of calorie and protein supply associated with clinical outcomes between medical and surgical intensive care unit. Methods: This was a retrospectively observational study. The medical records of patients who had been admitted to an intensive care unit for more than 72 hours were reviewed. The inclusion criteria of this study for patients included those who were 20 years or older, and those who had been admitted to intensive care unit for more than 72 hours, the exclusion criteria were that they received neither enteral nor parenteral nutrition. Their demographic characteristics, anthropometric measurements, nutrient-related data form enteral, parenteral, or intravenous, laboratory data and several clinical outcomes were collected. Results: There was no significant difference in baseline information and biochemical profile between the two groups except that white blood cells in medical patients was significantly higher than that in surgical patients (14.8±8.3 vs. 11.2±5.5 x103 cells/mm3, p=0.001). There were no significant associations of caloric or protein intake with clinical outcomes either in all patients or when patients were classified as medical or surgical patients. Disease severity, by contrast, significantly associated with clinical outcomes. The patients were further divided into two groups according to disease severity, Apache Ⅱ score 14 points. It was found that the calorie intake of patients with a score of ≦14 might correlated with the length of stay (LOS), but which still no statistically significant difference (p=0.057). Conclusions: Disease severity was still the most important factor to influence clinical outcomes. The correlation between caloric intake and LOS seemed to have a trend in patients with lower disease severity.