Selenium nutriture in total parenteral nutrition: intake levels

Area of Science:

• Human Nutrition
• Trace Element Metabolism
• Parenteral Nutrition

Background:

• Essential trace elements are crucial for human nutrition, but their requirements, functions, and interactions require further investigation.
• Total parenteral nutrition (TPN) offers a valuable model for studying nutrient status, particularly for less-understood elements like selenium (Se).
• Selenium deficiency and toxicity are both possible, highlighting the need to understand its levels in clinical settings.

Purpose of the Study:

• To evaluate the impact of long-term total parenteral nutrition (TPN) on selenium (Se) nutriture.
• To quantify selenium (Se) levels in various TPN solutions.
• To determine if standard TPN administration provides adequate selenium (Se) intake.

Main Methods:

• Analysis of multiple TPN solutions for the presence and quantity of selenium (Se).
• Utilized spectrophotometric methods to measure Se concentrations in dextrose and amino acid-based TPN formulations.
• Compared Se levels across different dextrose concentrations and manufacturers (Travenol, Abbott, McGaw).

Main Results:

• Selenium (Se) was undetectable in common TPN components like amino acids, electrolytes, and vitamins.
• Significant selenium (Se) concentrations were found in dextrose solutions from Travenol, Abbott, and McGaw Laboratories.
• Calculated that typical TPN volumes could deliver 200-400 micrograms of Se daily to adult patients.

Conclusions:

• Standard TPN regimens, particularly those containing dextrose, likely provide sufficient selenium (Se) to meet adult nutritional requirements.
• Further research is needed to establish optimal selenium (Se) requirements and monitor potential toxicity in patients receiving long-term TPN.
• The source and concentration of dextrose in TPN solutions significantly influence the total selenium (Se) delivered.