[Energy substrates in parenteral nutrition]

Area of Science:

• Nutritional Science
• Biochemistry
• Clinical Nutrition

Context:

• Total parenteral feeding (TPF) requires nutritionally efficient, safe, and easily administered substrates.
• Glucose is widely used but its benefits with insulin and alternatives are debated.
• Intravenous fat emulsions have become crucial for TPF energy supply.

Purpose:

• To evaluate the efficacy and safety of different energy substrates for TPF.
• To compare glucose-based nutrition with fat emulsions, including those containing medium chain triglycerides (MCT) and long chain triglycerides (LCT).
• To identify optimal nutritional strategies for TPF.

Summary:

• Fat emulsions, particularly MCT/LCT mixtures, are safe and effective calorie sources for TPF, providing essential fatty acids (EFA) and avoiding risks of high glucose loads.
• MCTs are rapidly metabolized, reducing deposition and oxidation issues, and are safe within specific limits.
• Combined fat emulsions and glucose show a superior nitrogen-sparing effect compared to glucose alone, and cyclic nocturnal TPN is a safe alternative for non-catabolic patients.

Impact:

• Fat emulsions offer a valuable alternative to glucose-only TPF, improving nutritional support and reducing complications like cholestasis.
• Understanding the metabolism and safe administration of MCT/LCT emulsions is key for optimizing TPF.
• This research informs clinical practice regarding the selection of energy substrates for parenteral nutrition.