Efficacy of glutamine dipeptide-supplemented total parenteral nutrition in critically ill patients: a prospective, double-blind randomized trial

Introduction

The aim of this study was to assess the clinical efficacy of glutamine dipeptide-supplemented total parenteral nutrition (TPN), defined by the occurrence of nosocomial infections or new organ failure as clinical endpoints.

Methods

Patients received a glutamine dipeptide-supplemented TPN (Glu-TPN) or a standard TPN (S-TPN). Entry criteria: adult patients in the ICU requiring TPN for 3 days or more and APACHE II score >12. Exclusion criteria: malnutrition or obesity, chronic renal or hepatic failure, immunocompromised patients and poor life expectancy. Both groups received isonitrogenous and isocaloric TPN. Nutritional needs were calculated: 0.25 g N/kg/day and 25 kcal/kg/day. The Glu-TPN group received 0.5 g/kg/day glutamine dipeptide and the S-TPN group a similar amount of amino acids. Vitals, sepsis and septic shock on admission, type of patient, daily SOFA score, daily calories administered, nosocomial infections based on CDC criteria, ICU and hospital lengths of stay and ICU mortality were recorded. Intent-to-treat and per-protocol analyses were done. Infections rates were compared using density rates and the ΔSOFA score was analyzed using ANOVA.

Results

One hundred and seventeen patients received any intervention, 53 assigned to Glu-TPN and 64 to S-TPN. Baseline characteristics were similar in both groups. Less new infections occurred in Glu-TPN patients: nosocomial pneumonia 8.04 versus 29.25 episodes-‰ days of mechanical ventilation (RR = 1.4; 95% CI = 1.2–1.7; P = 0.02), and urinary tract infections 2.5 versus 16.7 episodes-‰ days of urinary catheter (RR = 1.6; 95% CI = 1.3–2.1; P = 0.04). There were no differences in the incidence of catheter-related sepsis, primary bacteremias and intra-abdominal infections. There was a trend to improved ΔSOFA score in patients receiving Glu-TPN: ΔSOFA 72 hours (1.9 ± 2.4 vs 2.6 ± 2.7, P = 0.07). There were no differences in ICU and hospital lengths of stay or ICU mortality (15% vs 18%).

Conclusion

Glu-TPN used in critically ill patients for longer than 3 days significantly reduces the incidence of nosocomial pneumonias and urinary tract infections, and decreases the severity of organ failures.