The difference between enteral nutrition (EN) and parenteral nutrition

1.EN is supplemented by oral and nasogastric feeding into the gastrointestinal tract for digestion and absorption. PN is supplemented by blood circulation through intravenous injection

2.EN is more comprehensive and balanced. The nutrients supplemented by PN are relatively unitary

3.EN can be used for a long time and continuously. PN can only be used in a specific short term.

4.The long-term use of EN can improve the function of the gastrointestinal tract, enhance the physique and improve the physiological functions. The long-term use of PN can lead to the decline of gastrointestinal function and cause disorders of various physiological functions.

5.The cost of EN is lower than PN.

6.The complications of EN were less and relatively safe. The complications of PN were high.

1. Energy

Research shows that the average basal metabolic rate of cancer patients is almost equal to that of normal persons. If measuring individual energy consumption value cannot be achieved, the rule of thumb is suggested. Generally speaking, the energy demand of per bed patient is 20 ~ 25 kcal/d, while the energy demand of per patient who can get out of bed is 30 ~ 35 kcal/d, and then adjust the energy value according to the patient's age and stress condition. However, the weight (kg) mentioned here is the actual weight for non-obese patients, but for obese patients, it is correction weight (between ideal weight and actual weight), so as to avoid supplying excess energy.

2. Protein

Protein malignant tumor patients will suffer from excessive degradation of protein and reduction of protein synthesis in the early period, whose clinical manifestation includes losing thin tissue, reduction of the compliance and tolerance for anti-tumor treatment and shortening of survival time. Therefore, high protein diet is recommended, 1 ~ 1.2g/d for per common protein malignant tumor patients, and 1.2 ~ 2g/d for per severe nutrition consumption patients.

The calculation of this quantity is not familiar to us, but it will be clear in mention of the demand of normal persons. For a normal adult, daily protein demand is 0.8- 1.0 g/d; for a 60 kg adult, to meet this requirement, he needs to have about 300g staple food, 100g-150g meat, an egg, 50g soy products and 300 ml milk a day . Therefore, if a cancer patient doesn’t have enough food as a normal adult needs , there is needless to say 1 ~ 1.2g/d, thus the patient will face the protein deficiency which eventually affects his physical strength and immunity. The weight mentioned here is also calculated as the way described above.

3．Fat and Carbohydrates

For cancer patients, normal cells’ capability of oxidation of fatty acid is normal or increasing, while tumor cells’ ability of oxidation of fatty acid declined obviously. At the same time, the ability of tumor cells to absorb glucose is stronger than that of normal cells, leading to the damage of normal cells’ glucose tolerance. Therefore, it is suggested to appropriately improve the ratio of fat to energy and to reduce the ratio of carbohydrate to energy ; the ratio of fat energy supply to sugar energy supply can reach 1:1. When the patient is accompanied by hypertriglyceridemia, or by symptoms such as greasy, nausea and diarrhea, this ratio can be adjusted appropriately. When the patient is accompanied by diabetes, it is necessary to refer to the dietary guidelines for diabetes patients and the dietary guidelines for malignant tumor patients, so as to keep blood sugar normal and stable. The source of n-3 and n-9 fatty acids can be appropriately increased to reduce the cancer patients’ associated chronic inflammatory response.

4. Water:

Generally follow the physiological requirement ,30 ~ 40ml/d to maintain the daily urine volume at 1000-2000ml and adjust the water supply according to the amount of urine. For patients with heart, lung and kidney dysfunction, special attention should be paid to prevent excessive fluid, so as not to increase the burden of the organs.

5. Minerals and Vitamins:

Because oxidative stress markers increase and antioxidant level drops in cancer patients, the dose of antioxidant vitamins, but excessive oxidation could reduce the effect of anti-tumor therapy. There is no sufficient evidence that antioxidant vitamin and mineral supplement is beneficial clinically. Therefore, if patient diet is rich in variety and it can meet the target requirement, it is needless to supply additional vitamins and minerals.