Electrolytes

Effects of hyper-magnesemia on the body are what?

An excess of Mg++ severely restricts nerve and muscle activity. Remember... Mg++ is often used to treat pregnancy related eclampsia to reduce the risk of seizures.

What effect does hypo-natremia have on the body's cells?

As Na+ levels decrease in the extra-cellular fluid (ECF), water is pulled into the cells (because the Na+ concentration is now higher in the cells than in the ECF). The cells swell with the extra water and K+ is shifted out of the cell which will cause a potassium imbalance as well.

What are some nursing interventions for a patient with hyper-calcemia?

Assist in promotion of excretion of calcium; administer diuretics as ordered and encourage drinking 3,000-4,000ml of fluids daily, Monitor I&O and urine for lithiasis (stones).

What is the function of calcium in the body?

Beside bones and teeth, calcium is required for normal blood clotting. Calcium has a depressing or sedative effect on neuromuscular irritability and promotes normal nerve impulse transmission. It also helps regulate muscle contraction and relaxation (the heart is a muscle).

To measure a patient's electrolytes, a sample of what is needed?

Blood; the electrolytes are found and measured in the serum portion of blood. Blood serum is the clear yellow liquid part of blood. (serum electrolytes are reported on lab tests)

Potassium imbalances are most worrisome due to their ability to cause which life-threatening problem?

Cardiac arrhythmias/complications

Describe tetany and it's signs.

Excessive muscle cramps, laryngeal spasm, stridor, contraction of facial muscle (Chvostek's sign), and carpal spasms (Trousseau's sign), and pedal spasms.

What is the charge on an anion?

The anion is negatively charged

What effect does hyper-natremia have on the body's cells?

The body attempts to conserve water through renal reabsorption in the kidneys (retaining water). Hyper-natremia causes fluid to shift from the cells to the interstitial spaces; this results in cellular dehydration. Hyper-natremia is caused by an excess of Na+ or a decrease in body water.

What is the charge on a cation?

The charge on a cation is positive (remember that the t in cation looks like a + sign).

What is the correlation between the amount of Mg++ and K+ excreted?

The kidneys do not conserve K+ if a Mg++ deficiency is present; the kidneys will conserve Mg++ at the expense of K+.

What are the causes of hyper-magnesemia?

This rarely occurs when kidney function is normal. 3 major causes: Impaired renal function, excess magnesium administration, and DKA (when there is severe water loss).

Normal magnesium (Mg++) level is what?

1.5 to 2.4 mEq/L. Magnesium is essential for integrity of nervous tissue, skeletal muscles, and cardiac functioning.

Normal serum sodium (Na+) level in the body is what?

135-147 mEq/L (milli-equivalents per liter). Diet is the major source of Na+; unlike the other electrolytes, Na+ must often be limited in the diet.

Normal serum potassium (K+) level in the body is what?

3.5-5.0 mEq/L. 98% of the body's K+ is in the cells. 80% to 90% of K+ is excreted via the kidneys, the remainder is excreted in feces, and perspiration. The kidneys will always choose to conserve Na+ and excrete K+. Any condition which decreases urine output causes K+ retention (example: renal failure).

The normal serum calcium (Ca++) level is what?

4.5 mEq/L to 5.8 mEq/L. 99% of Ca++ is stored in the bones and teeth. Calcium is moved from the bones to the blood as it is needed. Vitamin D, calcitonin, and parathyroid hormone influence the absorption and utilization of calcium.

How does hypo-kalemia occur?

A major cause of K+ loss is renal excretion; other causes include GI losses from gastric suctioning or prolonged vomiting, severe diarrhea, and fistulas. Diuretics also promote hypokalemia. Excessive perspiration can also lead to potassium depletion. A slight decrease in K+ has a profound effect.

What is an electrolyte?

A substance that becomes either positively or negatively charged when it is dissolved in water: electrolytes are charged ions which are classified as cations or anions

What effect does hyper-kalemia have on the body?

Abnormal heart rhythm; arrhythmia can be life-threatening, slow heart rate, and weakness.

What are causes of hypo-calcemia?

Hypo-calcemia is caused by the infusion of excess amounts of citrated blood, excessive loss through diarrhea, inadequate dietary intake, decreased function of or surgical removal/damage of the parathyroid glands.

What is the relationship between hypo-magnesemia and hypo-kalemia?

If Mg++ levels are low, the kidneys will excrete potassium, which often causes hypo-kalemia.

What is hypo-kalemia?

K+ < 3.5 mEq/L.

Nursing interventions for a patient with hypo-calcemia include what?

Monitor vital signs and respiratory status, keep tracheotomy tray and ambu bag at bedside in case of laryngeal spasm, monitor telemetry, lab values, and I & O.

What are the nursing interventions for hypo-magnesemia?

Monitor vital signs, I & O, telemetry, and respiratory status. Assess neuromuscular status and institute seizure precautions. Administer Mg++ as ordered.

What are the signs and symptoms of hypo-magnesemia?

Muscle weakness, tremors, seizures, paresthesias, nystagmus, and cardiovascular manifestations.

What are the functions of Na+ (sodium)?

Na+ controls the extracellular fluid volume because water follows Na+ in the body. Na+ increases cell membrane permeability and stimulates conduction of nerve impulses. Na+ is important in controlling contractility of muscles, especially the heart (which is a muscle).

Which compartment is the majority of Na+ located?

Na+ is the major extracellular electrolyte. It is primarily excreted via the kidneys.

What is hypo-natremia?

Na+ level < 135 mEq/L.

What is hyper-natremia?

Na+ level > 147 mEq/L.

Signs and symptoms of hypo-calcemia include what?

Neuro-muscular irritability, seizures, paresthesias, Chvostek's and Trousseau's signs, (tetany), muscle stiffness, myalgias, spasms (laryngospasm), and heart arrhythmias.

Nursing interventions for hyper-magnesemia include what?

Promote urine excretion by administering diuretics and fluids; monitor I & O and respiratory function.

What is the major cause of hyper-kalemia?

Renal disease is the major cause of hyper-kalemia; the body is unable to excrete K+. Severe tissue damage from trauma (crush injuries) and burns force K+ from damaged cells. These injuries often cause shock which results in reduced kidney output.

Hyper-calcemia is caused by what?

Too much calcium leaving the bones and entering the blood; this can happen when a patient is immobile. Neuromuscular activity is depressed by the high levels of calcium. Renal calculi (stones) may form in the kidneys when serum calcium levels are high.

Kayexalate is used to treat which electrolyte disorder? How does it work?

Used to treat hyperkalemia. It causes loose stools and the patient will lose potassium with these stools. K+ levels in the body will be decreased by K+ loss in the loose stools.

What effect does hypo-kalemia have on the body?

Weakness, fatigue, muscle cramps, constipation, and abnormal heart rhythms; arrhythmias can be life-threatening.