Question

Sodium (Na/Natrium): what are the normal functions of sodium in the body? a. Etiology: explain how each of the following could cause hyponatremia: - excessive ADH - excessive, rapid water ingestion - diuretics - hypotonic infusions - Addison disease/adrenal insufficiency - pituitary disorders - severe burns - congestive heart failure b. Clinical Manifestations: explain why each of the following could occur in patients with hyponatremia: - fatigue - cramps - nausea, vomiting, anorexia - confusion, restlessness, seizures, headache - cerebral herniation - coma and death c. Etiology: explain how each of the following could cause hypernatremia: - difficulty swallowing fluids - high sodium intake with low water intake - watery diarrhea - loss of thirst mechanism - diabetes insipidus - diuretics - hypertonic infusions - tube feeding - advanced age - excessive diaphoresis d. Clinical Manifestations: explain why each of the following could occur in patients with hypernatremia: - thirst - oliguria - confusion, seizures - coma and death - weight loss - orthostatic hypotension - tachycardia

Answer 1

Sodium is the most abundant electrolyte in the ECF.It is the primary determinant of ECF osmolality.Decreased sodium is associated with parallel changes in osmolality.it has a major role in controlling water distribution throughout the body,because it does not easily cross the cell wall membrane and because of its abundance and high concentration in the body.it is the primary regulator of ECF volume.it also functions in establishing the electrochemical state necessary for muscle contraction and transmission of nerve impulses.

a Excessive ADH=it is due to the an excess of water rather than a deficiency of sodium.

Rapid water ingestion= it is a rare condition that originated from over hydration.it develops only because the water intake exceeds the kidneys ability to eliminate water.

diuretics=loop diuretics inhibit the transprt of sodium in the renal medulla and prevent the generation of a maximal osmotic gradient.

hypotonic solutions=it contain 30.8 -74mEq/L sodium with 5%glucose may lead to serious hyponatremia

Addisons disease=Adeficiency of aldosterone ,as occurs in adrenal insufficiency ,also predisposes to hyponatremia.

Burns=it is a result of decreased sodium in theblood from the destroyed tissue caused by burns in the body.

pituitary doisorders=

CHF=Hyponatremia in patients with CHF is primarily caused by increased activity of arginine vasopressin

b When there is too much water in the blood ,the body compensates by attempting to excrete excess water in urine ,and also shifting this excess water inside cell walls ,causing them to swell.if the swelling occurs in muscles and fats they have plenty of ability to shrink and expand,but the brain does not.it is surrounded by skull and any swelling of the brain causes pressure and result in headache,seizures,coma and death.because sodium is an ion ,it has an electrical charge to transiently exist within an area of the body or in an area of cell wall.nerves utilize this charges to send messages to the brain and to direct the muscles to contract or to relax.Without sufficient sodium levels in the body,this process is hampered,which can result in extreme fatigue,muscle weakness or cramping.

c watery diarrhea=it results in hypotonic watery diarrhea resulting in ignificant loss of free water and a higher concentration of sodium in the blood

diabetes insipidus=With diabetes insipidus the unregulated release and subsequent activity of vasopressin leads to hyponatremia caused by excess fluid retention.

diuretics=it causes an increase in serum sodium concentration which creates an osmotic gradient between the extracellular and intracellular fluid in brain cells causing movement of water into the extracellular space inorder to maintain the osmotic equilibrium at the expense of a decrease in the cell volume.thus the symptoms of hypernatremia are attributed to brain cell shrinkage and are related to both the severity and the rapidity of the rise in the serum sodium level.

hypertonic solutions-

tube feeding=In patients who have tube feeding ,tube feeding water protein ratios may be higher than those ordinarily well tolerated.hypernatremia occurs predominantly due to dehydration and not to excess salt.

advanced age=hypernatremia in adults is most commonly due to the combination of inadequate fluid intake and increased fluid losses.

excessive diaphorisis=certain conditions may cause excess of sodium in the blood sch s diaphorisis from not drinking adequate water.

d thirst occurs due to decreased intake of fluid level resulting in the accumulation of salt in the body.confusion ,muscle twitching or spasms occurs from brain cell shrinkage .with severe elevations of sodium result in seizures and comas.