In addition to vitamins, there are also invisible substances in the body, namely minerals. The constant ones are calcium, phosphorus, magnesium, potassium, sodium and chlorine, and the trace ones are iron, iodine, zinc, selenium, copper, chromium and molybdenum. Because people grow on the earth, and in the process of evolution and life, they are constantly exchanging substances with the environment. These substances play a huge role in the human body, but when these substances are not balanced, there will also be fatal problems.
Calcium: There is 1000-1200 grams of calcium in normal human body, and 99.3% is concentrated in bone and teeth.
Calcium is a headache for kidney disease, because the kidney is the main way of calcium excretion. The total amount of calcium filtered by the normal glomerulus can reach 10 grams per day, and the reabsorption rate can be adjusted automatically according to the blood calcium situation. The low reabsorption rate of blood calcium can reach 100%, and the high blood calcium can increase the calcium excretion, which is about 200 mg per day, and up to 500 mg at the high time. Other excretory pathways are relatively stable. Sweat is about 20 mg per day, hair and nails are about 60 mg, and feces are about 100 mg. So the kidney plays a decisive role in the regulation of calcium in the body. If the kidney loses its function, the regulation of calcium will disappear.
The absorption of calcium is mainly through the intestinal tract to absorb the calcium in food. The absorption rate is low, about 20% in adults. The older the age, the lower the absorption rate, and there are many constraints.
The regulation system of calcium stability in the body is also very complex, mainly parathyroid hormone, calcitonin and active vitamin D3 interact, restrict and coordinate with each other, but the synthesis and regulation of active vitamin D3 are out of control when the kidney loses its function, which interferes with calcium stability, and the restriction, control and coordination among the three are out of control, resulting in irregular migration of calcium in the body and disorderly deposition, leading to serious consequences.
The control of calcium starts with intake, absorption and excretion, and controls the total amount of calcium in the body.
For calcium intake, it is not necessary to consider the calcium content of food now. Generally, high-calcium food is also high-phosphate food, and should be taken as little as possible. Therefore, calcium tablets are the main source of calcium intake, and the daily use and dosage of calcium tablets should also be determined according to many circumstances.
The main influencing factor of calcium absorption is the amount of active vitamin D3.
In terms of calcium excretion, we can only pay attention to the unobstructed intestinal tract and keep calcium through the excretory channel of stool.
For dialysis patients, another way to exchange calcium with the outside world is dialysate. The calcium concentration of dialysate is generally 1.5, the low calcium is 1.25, and the high calcium is 1.75, which can be selected according to the level of blood calcium. However, there are many individual differences in the exchange of dialysate calcium and blood calcium, which need to be determined according to your own situation.
In terms of internal stability, it is mainly to adjust the relationship between parathyroid hormone and active vitamin D3, so the use and dosage of active vitamin D3 become the key to internal stability. Hyperparathyroidism is one of the most common complications of dialysis patients. The treatment methods include active vitamin D3 pulse, kanacese hydrochloride PTH reduction treatment and surgical removal of parathyroid gland, which can be selected according to your own situation.
Phosphorus: 600-700 grams of phosphorus in normal human body, 85% of which is concentrated in bone and teeth, and the rest half in muscle tissue.
Phosphorus intake mainly depends on food, and there are more foods rich in phosphorus; The absorption is mainly in the small intestine. The absorption rate of phosphorus is relatively high, about 70%. When there are metal cations such as calcium, magnesium, iron and aluminum in the intestine, they will combine with phosphorus and hinder the absorption of phosphorus, but active vitamin D3 will promote the absorption of phosphorus in the intestine. Phosphorus is mainly excreted by the kidney, which excretes about 650 mg of inorganic phosphorus every day.
For dialysis patients, phosphorus is a big problem. Increasing nutrition leads to high phosphorus. High phosphorus will stimulate the increase of parathyroid hormone and also lead to calcification of non-bone tissue. Therefore, the control of phosphorus is long-term and arduous.
The most basic control of phosphorus is the control of intake, which is the basis. Eat less or do not eat foods with high phosphorus content. In addition, it is absorption. Use some phosphorus binders to combine phosphorus with calcium, aluminum and other cations in the intestine to reduce absorption by the intestine. Calcium binders, such as calcium carbonate and calcium acetate, are preferred because calcium is supplemented and phosphorus is reduced at the same time; If the condition of blood calcium does not allow the use of calcium-containing binders, non-calcium-containing binders such as Renagel can be used. In special cases, aluminum hydroxide and other binders can be used. Pay attention to the dose and time of application. In the process of phosphorus excretion, we have lost the regulation of kidney to phosphorus, so it is very important to keep the stool unblocked.
The main channel of phosphorus excretion for dialysis patients is dialysis. Maintaining adequate and regular dialysis is an effective means to ensure normal blood phosphorus.
Therefore, in the control of phosphorus, the control of phosphorus intake is the basis, the full and regular dialysis is the basic means, the use of phosphorus binder is the routine method, and the maintenance of smooth stool is an effective assistant.