Enteral hyperalimentation in head injury

Area of Science:

• Nutrition Science
• Critical Care Medicine
• Neurological Surgery

Background:

• Severe head injury (SHI) often leads to a hypermetabolic state, increasing nutritional requirements.
• Meeting these increased caloric and protein demands is crucial for patient recovery and outcomes.
• Enteral nutrition is a preferred route for nutritional support in critically ill patients.

Purpose of the Study:

• To evaluate the efficacy of enteral hyperalimentation in meeting nutritional demands in SHI patients.
• To assess the impact of increased protein intake on nitrogen balance in this population.
• To explore the feasibility and complications of prolonged enteral feeding in acute SHI.

Main Methods:

• A consecutive series of 20 comatose SHI patients received enteral nutrition.
• Patients were randomized into two groups: 14% or 22% protein calories.
• Nutrition was advanced to 140% of measured caloric expenditure, with 7-day balance periods.
• Indirect calorimetry was used to measure energy expenditure.

Main Results:

• Both feeding regimens were delivered enterally with few metabolic complications.
• Higher protein intake (22% vs 14%) showed a trend towards improved nitrogen balance, but not statistically significant.
• Despite hyperalimentation, most patients remained in negative nitrogen balance, with weight loss and decreased serum albumin observed.
• Urinary urea nitrogen was found to be an unreliable measure of nitrogen excretion.

Conclusions:

• Enteral hyperalimentation is feasible for prolonged periods in acute SHI patients.
• Increasing protein content from 14% to 22% may offer some benefit to nitrogen retention.
• Achieving nitrogen equilibrium remains challenging in SHI patients, even with aggressive nutritional support.