Aims: To determine whether a specific high-protein enteral formula with a similar caloric percentage of fat and carbohydrates achieves greater control over glycemic levels and reduces insulin requirements in hyperglycemic critically ill patients when compared to a control high-protein enteral formula.
Design: A prospective, randomized, controlled, single-blind trial in two University Hospital Intensive Care Units in Spain.
Methods: We enrolled 50 patients with diabetes mellitus or stress hyperglycemia with basal glycemia > or =160 mg/dl and indication for enteral nutrition > or =5 days. Patients with severe kidney failure, liver failure or obesity were excluded from the study. In the first 48 h of admission, after randomization, 26 patients received the study diet and 24 patients received the control diet. The variables were monitored for 14 days. The Harris-Benedict formula with a fixed stress factor of 1.2 was used to calculate caloric needs. Insulin was administered by continuous infusion. An intention-to-treat analysis was performed.
Results: On admission, there were no differences between the study and control group in plasma glucose levels (mg/dl) (190.9+/-45 vs 210.3+/-63) and capillary glucose levels (mg/dl) (226.1+/-73 vs 213.8+/-67). After the feeding trial, there were differences between the study and control group in plasma glucose levels (mg/dl) (176.8+/-44 vs 222.8+/-47, P=0.001), capillary glucose levels (mg/dl) (163.1+/-45 vs 216.4+/-56, P=0.001), insulin requirements/day (IU) 8.73 (2.3-27.5) vs 30.2 (21.5-57.1) (P=0.001), insulin/received carbohydrates (UI/g) 0.07 (0.02-0.22) vs 0.18 (0.11-0.35) (P=0.02) and insulin/received carbohydrates/kg 0.98 (0.26-3.59) vs 2.13 (1.44-4.58) (P=0.04). These differences remain in a day-to-day comparison. There were no differences in the analytical tests, or in digestive or infectious complications. Intensive Care Unit length of stay, mechanical ventilation and mortality were similar in both groups.
Conclusions: Hyperglycemic critically ill patients fed with a high-protein diet with a similar caloric percentage of fat and carbohydrates show a significant reduction in plasma glucose levels, capillary glucose levels and insulin requirements in comparison to patients on a conventional high-protein diet. This better glycemic control do not modify Intensive Care Unit length of stay, infectious complications, mechanical ventilation and mortality.