Disorders of Salt and Water Flashcards
What is hypernatremia by definition?
The water content of the body fluid is deficient in relation to the sodium content (serum sodium >145). There is either way to much salt or not enough water.
What causes hypernatremia?
Inadequate fluid intake or excess fluid loss
What are the clinical features of hypernatremia?
Neurological manifestations include thirst, restlessness, irritability, disorientation, lethargy, delirium, convulsions, and coma. Brain cells shrink!
Other findings include dry mouth and dry mucous membranes, flushed skin, tachycardia, hypotension, fever hyperreflexia and oliguria and anuria.
Diabetes insipidus is usually indicated diagnostically by….
Low urine sodium and polyuria
How is hypernatremia treated?
Hypernatremia should be treated on an inpatient basis. Free water may be administered orally or IV/SQ. Hypovolemia should be treated first and then hypernatremia second.
What is a caution when treating hypernatremia?
Rapid correction of hypernatremia can cause pulmonary or cerebral edema, especially in patients with DM.
What is hyponatremia?
Plasma sodium concentration of less than 135. Signs and symptoms may not occur until the concentration falls below 125.
What are the clinical features of hyponatremia?
Symptoms include lethargy, disorientation, muscle cramps anorexia, hiccups, n/v, and seizures.
Signs include weakness agitation, hyporeflexia, orthostatic hypertension, and cheyne-stokes respirations.
How is hyponatremia treated?
treat hypovolemia on an impatient basis, especially if symptomatic or if serum sodium is less than 125. Treatment usually requires fluid restriction.
What is a caution while treating hyponatremia?
Overly rapid correction can cause central pontine myelinolysis, resulting in neurologic damage.
What is diabetes insipidus?
DI is a disorder of water, the neurogenic form is caused by deficient secretion of arginine vasopressin (ADH) from th eposterior pituitary. The nephrogenic form is caused by kidneys that are unresponsive to normal vasopressin levels.
What are the clinical features of DI?
polyuria, nocturia and polydipsia are the main symptoms
What is the treatment for DI?
Neurogenic or central DI is best treated with parenteral or intranasal desmopressin. Diuretics, chlorpropamide, or carbamazepine can be used in patients with mild disease.
What are the characteristics of volume depletion?
Volume depletion occurs when body fluids are lost from the extracellular component at a rate that exceeds intake.
What are the clinical features of volume depletion?
volume depleted patients become thirsty, and urinary output decreases. Mild volume depletion can cause increased heart rate, fatigue, and muscle cramps. Severe hypovolemia results in general hypotension , signs of ischemia and shock.
