Water exchange in the body
In many diseases of , water exchange in the body of is crucial. So, with chronic heart failure, hypertension, neglected atherosclerosis, diseases of the genitourinary system, water and water-salt metabolism usually happens
is broken and edema develops. Therefore, the regulation of water-salt metabolism is important in the treatment of a patient.
Let us first consider the issue of normal water metabolism in the human body.
The water content in the child's body at birth is up to 80% of body weight, then gradually decreases to 65%, and this value remains constant throughout life, regardless of gender and age.
Water in the human body can be in a free or bound state. Being in a free state, it easily passes from cells to the intercellular space, into the lymph and blood plasma. If water is bound by proteins, it is firmly retained in cells and tissues. A healthy person in the body constantly observes water-salt balance, that is, a certain balance of water and salts, both in bound and free state. If this equilibrium is disturbed, a disease occurs.
Water exchange is a combination of the processes of absorption of drinking water, the formation of water during the oxidation of fats, proteins and carbohydrates, its distribution between the intracellular and extracellular space, on the one hand, and the release of water by the kidneys, lungs, skin and intestines, on the other.
In an adult person who has a weight of 70 kg, the total water content in the body reaches 50 kg. Out of this amount, only 15% is for blood plasma and lymph, the remaining 50% is water, which is inside the cells in a bound state. In a state of water balance, the amount of water consumed is equal to the amount of water released.
The water balance is composed of the following values: amount of drinking water - 1000 ml;water,
composition of food products - 720 ml;water, formed during the oxidation of fats, proteins and carbohydrates - 320 ml. In sulei, under normal conditions, a person consumes up to 2.5 liters of water. Of this amount, about 1100 ml is released through the kidneys, 400-450 ml - through the skin, 300-350 ml - through the lungs and about 150 ml - with feces. When the environmental conditions( temperature, pressure, food character) change, these data can vary greatly in one direction or the other. However, the water-salt balance in the body is restored very quickly, so: how it is a vital factor.
The regulators of water metabolism are the central nervous and endocrine systems. Violation of the regulation function of water-salt metabolism can cause severe changes in metabolism and cause either water retention in the body, or, conversely, increased its removal leading to dehydration.
The state of the cardiovascular system and the content of proteins in the blood plasma are of great importance for maintaining the body's water balance. The degree of water retention in tissues is significantly influenced by the content of sodium and potassium salts in the cells and extracellular fluid. Due to these salts, a certain osmotic pressure is created in the cells. The salt composition of the intra- and extracellular fluid is different. If extracellular fluid has a great similarity to sea water and the presence of salts in it can vary greatly, the composition of the intracellular fluid is almost always constant and retains its chemical identity. This is due to the presence of cell membranes, which, while retaining potassium, refuse sodium and calcium. In cells, magnesium ions, potassium, sulfate groups usually prevail, and outside cells - chlorine, sodium, calcium and protein fractions.