Glucose infusion improves endogenous protein synthesis efficiency in multiple trauma victims

Area of Science:

• Metabolic and Nutritional Support
• Trauma and Critical Care Medicine

Background:

• Excessive nutritional support in stressed patients carries metabolic costs.
• Major injury decreases protein synthesis efficiency (PSE) due to amino acid use in gluconeogenesis.

Purpose of the Study:

• To test if glucose infusion alone, not exceeding resting energy expenditure (REE), can restore PSE in early post-trauma days.
• To determine if this approach primes the body for subsequent full nutritional support.

Main Methods:

• Eight severely injured, hypermetabolic patients in the Trauma Intensive Care Unit (TICU) were studied.
• Integrated measurements of whole-body fuel-substrate kinetics were performed, including indirect calorimetry, 15N-glycine infusion for protein kinetics, and labeled glucose infusions.
• Two studies per patient: early post-trauma and after 4-5 days of continuous hypertonic glucose infusion (80% REE).

Main Results:

• Hypertonic glucose infusion significantly increased PSE (14%) and respiratory quotient (RQ) (31%).
• Observed significant decreases in endogenous glucose appearance rate (55%) and negative nitrogen (N) balance (48%).
• Plasma growth hormone and insulin levels also increased significantly.

Conclusions:

• Hypertonic glucose infusion alone appears sufficient for physiological adaptation in the immediate post-trauma period.
• This therapy restores normal PSE, potentially protecting the body's labile protein stores.
• It may facilitate the transition to full nutritional support in critically injured patients.