This book describes Hyponatremia, Diagnosis and Treatment and Related Diseases
Hyponatremia indicates low sodium in the blood that can give rise to symptoms of lethargy, fatigue, muscle weakness, even confusion and coma.
Hyponatremia is the term for low Sodium in the blood.
Normal blood Sodium ranges from 135 and 145 milliequivalents per liter (mEq/L).
Hyponatremia happens when blood's sodium levels are too low (below 135 mEq/L).
Hyponatrmia is a disorder in which the quantity of sodium in the blood is lower than normal
It happens when water and sodium are out of balance.
There is either too much water or not enough sodium in the blood.
Sodium is an essential electrolyte (mineral) that is very important for maintaining blood pressure.
Sodium regulates the body's fluid balance.
Sodium will maintain the balance of water in and around the cells.
Sodium is also required for nerves, muscles, and other body tissues to function properly.
Sodium is present mostly in the body fluids outside the cells (extra-cellular).
Extra-cellular sodium level indicates only 2 per cent of the total body sodium.
When the amount of sodium in fluids outside cells falls below normal, the water transfers into the cells to balance the levels
This induces the cells to swell with too much water.
Brain cells are particularly sensitive to swelling, and this produces many of the symptoms of low sodium.
With low blood sodium (hyponatremia), the imbalance of water to sodium is produced by one of 3 disorders:
Euvolemic hyponatremia -- Total body water increases but the body's sodium content is the same
Hypervolemic hyponatremia -- Both sodium and water content in the body rise, but the water gain is greater
Hypovolemic hyponatremia -- Both water and sodium are lost from the body but the sodium loss is greater
Sodium is a major determinant of intracellular volume of cells and intracellular osmolarity.
It is an also an important cofactor in many metabolic processes.
The resting membrane potential and excitable tissues like nerves are mainly determined by ratio of intracellular to extra-cellular sodium concentrations.
Plasma and extra-cellular sodium levels are affected by many factors particularly acid based balance.
Acidosis moves sodium out of cells while alkalosis shifts sodium into cells.
Hyponatremia often happens with loss of salt through:
Gastrointestinal - severe vomiting and diarrhea
Urinary loss especially after use of sodium wasting diuretics (water pills)
Sweating
Fistula
Diabetes mellitus.
Causes of low sodium in blood are:
Certain medicines, including diuretics, antidepressants and pain medications
Some medicines, such as some water pills (diuretics), antidepressants and pain medicines can disrupt the normal hormonal and kidney processes that maintain sodium concentrations within the healthy normal range.
Chronic, severe vomiting or diarrhea and other causes of dehydration
This causes the body to lose electrolytes, such as sodium, and also increases ADH levels
Kidney disease or kidney failure
Liver disease
Heart problems, including congestive heart failure
Congestive heart failure and certain diseases involving the kidneys or liver can induce fluids to collect in the body, which dilutes the sodium in the body, lowering the overall level of sodium.
Primary polydipsia, a disorder in which excess thirst makes the person drinks too much water
Drinking excessive amounts of water can produce low sodium by overwhelming the kidneys' ability to excrete water.