Final answer:
Fiber is not found in a Total Parenteral Nutrition admixture because it requires digestion in the gastrointestinal tract; TPN admixtures contain glucose, amino acids, lipids, vitamins, and minerals.
Step-by-step explanation:
A Total Parenteral Nutrition (TPN) admixture is a complex solution used to provide nutrition intravenously to patients who are unable to eat or absorb nutrients through their gastrointestinal tract. A TPN solution typically contains a balance of glucose, amino acids, lipids, vitamins, and minerals. One component that is not found in a TPN admixture is fiber, because fiber can only be administered orally or through enteral feeding as it requires digestion in the gastrointestinal tract for its benefits.