PHYSIOLOGY OF PHYSIOLOGY OF WATER-WATER-

ELECTROLYTES ELECTROLYTES BALANCEBALANCE

Total body water in adult human Total body water in adult human

60-70 %60-70 %

It consists of It consists of Extra cellular water – 20 %Extra cellular water – 20 % Intracellular water – 40 % Intracellular water – 40 %

Extra cellular water consists of Extra cellular water consists of Intravascular water or blood plasma – 5 %Intravascular water or blood plasma – 5 % Interstitial water – 15 %Interstitial water – 15 %

Function of body fluidsFunction of body fluids

1. Facilitate the transport of nutrients, 1. Facilitate the transport of nutrients, hormones, proteins, other molecules into the hormones, proteins, other molecules into the cellscells

2. Aid in the removal of cellular metabolic 2. Aid in the removal of cellular metabolic waste productswaste products

3. Provide the medium in which cellular 3. Provide the medium in which cellular metabolism takes placemetabolism takes place

Function of body fluidsFunction of body fluids

4. Regulate body temperature4. Regulate body temperature 5. Provide lubrication of musculoskeletal 5. Provide lubrication of musculoskeletal

jointsjoints 6. Act as a component in all body cavities 6. Act as a component in all body cavities

(pericardial, pleural, spinal, peritoneal fluid – (pericardial, pleural, spinal, peritoneal fluid – 1 % of TBF) 1 % of TBF)

PeculiaritiesPeculiarities Fatty tissue contains less water than muscle.Fatty tissue contains less water than muscle. Older adults tend to lose muscle mass as they Older adults tend to lose muscle mass as they

age, thereby decreasing the percent of body age, thereby decreasing the percent of body waterwater

Infants have a higher percentage of body Infants have a higher percentage of body weight as waterweight as water

Electrolyte composition of body Electrolyte composition of body fluidsfluids

The primary body electrolytes are sodium, The primary body electrolytes are sodium, potassium, chloride, calcium, magnesium, potassium, chloride, calcium, magnesium, phosphorus, hydrogen, bicarbonate.phosphorus, hydrogen, bicarbonate.

Major ICF electrolytes are potassium and Major ICF electrolytes are potassium and magnesium, and phosphorus.magnesium, and phosphorus.

Major ECF electrolytes are sodium and Major ECF electrolytes are sodium and chloride, and bicarbonate.chloride, and bicarbonate.

Daily water balanceDaily water balance Enters to body = 1,5-2,5 lEnters to body = 1,5-2,5 l With foodWith food With drinksWith drinks Cellular metabolismCellular metabolism

Excreted with lungs (0.5 l), skin (0.5-0.6 l), Excreted with lungs (0.5 l), skin (0.5-0.6 l), GIT (0.1-0.2 l), kidneys (0.8-1.5 l)GIT (0.1-0.2 l), kidneys (0.8-1.5 l)

Organs, which maintaining water- Organs, which maintaining water- salts homeostasissalts homeostasis

LungsLungs HeartHeart PituitaryPituitary Adrenal cortexAdrenal cortex Para thyroidsPara thyroids KidneysKidneys Blood vesselsBlood vessels

Renal regulationRenal regulation Produce renin, which activates angiotensin I, Produce renin, which activates angiotensin I,

which converted to angiotensin II (power which converted to angiotensin II (power vasoconstrictor), which increase glomerular vasoconstrictor), which increase glomerular filtration and urine output (if serum sodium is filtration and urine output (if serum sodium is low with normal). And opposite reaction is in low with normal). And opposite reaction is in the case of high serum sodium.the case of high serum sodium.

Endocrine regulationEndocrine regulation

In the hypothalamus is present the primary In the hypothalamus is present the primary regulators of water - thirst center.regulators of water - thirst center.

In the posterior hypothalamus is present the In the posterior hypothalamus is present the osmoreceptors which is respond to changes in osmoreceptors which is respond to changes in ECF osmolarity (increases of ECF osmolarity ECF osmolarity (increases of ECF osmolarity helps to secretes vassopressine - ADH).helps to secretes vassopressine - ADH).

Adrenal glands produce aldosterone.Adrenal glands produce aldosterone. Parathyroid secretes parathyroid hormones.Parathyroid secretes parathyroid hormones.

Cardiovascular regulationCardiovascular regulation The cardiovascular system regulates fluid The cardiovascular system regulates fluid

volume, pressure sensors, and atrial natriuretic volume, pressure sensors, and atrial natriuretic factor. factor.

Gastrointestinal regulationGastrointestinal regulation Secretion and absorption of fluids.Secretion and absorption of fluids.

Pulmonary regulationPulmonary regulation The elimination process and water loss with The elimination process and water loss with

hyperventilation and mechanical ventilation.hyperventilation and mechanical ventilation.

Role of electrolytesRole of electrolytes 1. Its conduct electricity across cell 1. Its conduct electricity across cell

membranes; they are needed for life processes membranes; they are needed for life processes to occur.to occur.

2. Maintain osmolality of body fluid 2. Maintain osmolality of body fluid compartmentscompartments

3. Regulate balance of acids and bases3. Regulate balance of acids and bases 4. Aid in neurological and neuromuscular 4. Aid in neurological and neuromuscular

conductionconduction

Electrolyte balanceElectrolyte balance 1. For a homeostatic condition to exist, equal 1. For a homeostatic condition to exist, equal

amounts of anions and cations must be present amounts of anions and cations must be present on either side of the cell membrane.on either side of the cell membrane.

2. They can move from one to another side.2. They can move from one to another side. 3. Extra cellular electrolytes are found in the 3. Extra cellular electrolytes are found in the

interstitial and intravascular fluids where there interstitial and intravascular fluids where there is a balance of cations and anions. is a balance of cations and anions.

Regulation of electrolytesRegulation of electrolytes 1. Kidneys1. Kidneys 2. Endocrine system2. Endocrine system 3. Gastrointestinal tract3. Gastrointestinal tract

Meaning of main ionsMeaning of main ions Sodium (135-150 mmolSodium (135-150 mmol//L)L) Potassium (3.8-5.2 mmolPotassium (3.8-5.2 mmol//L)L) Chloride (98-105 mmolChloride (98-105 mmol//L)L) Calcium (2.35-2.75 mmolCalcium (2.35-2.75 mmol//L)L) Magnesium (0.70-1.1 mmolMagnesium (0.70-1.1 mmol//L)L)

Thank you!Thank you!