Intravenous nutrient solution has glucose, fat milk, glucose has 5% glucose, 50% glucose, fat milk has 20% and 30% concentration, generally amino acids are not used as energy, but only to maintain the positive nitrogen balance of the patient. One gram of glucose can produce 4000 calories of energy after complete utilization in the body, and one gram of fat can produce 9000 calories of energy after complete combustion. Generally, the normal human body needs about 1200-1500 kcal per day, so if we want to configure parenteral nutrition solution, we usually need about 200 grams of glucose, and if it is 30% concentration of fat milk, we need about 200ml or so, it is recommended to infuse through the central vein, if the peripheral infusion is too long, it may lead to painful irritation of blood vessels, phlebitis, etc.