Competency 11: Knowt Play Cards

What laboratory studies can help assess fluid and electrolyte imbalances?

CBC, serum electrolytes, BUN, creatinine, urine pH, urine specific gravity, and ABGs.

What is the normal sodium (Na⁺) range?

135-145 mEq/L.

What is the normal potassium (K⁺) range?

3.5-5.0 mEq/L.

What is the normal total serum calcium range?

8.6-10.2 mg/dL.

What is the normal ionized calcium range?

4.5-5.1 mg/dL.

What is the normal chloride range?

97-107 mEq/L.

What is the normal magnesium range?

1.3-2.3 mEq/L.

What is the normal phosphorus range?

2.5-4.5 mg/dL.

What is the fasting blood glucose range?

80-110 mg/dL.

What is the normal arterial bicarbonate (HCO₃⁻) range?

22-26 mEq/L.

Where is sodium primarily located?

In the extracellular fluid (ECF).

What are major functions of sodium?

Regulating ECF osmotic pressure and water balance.

What is hypernatremia?

A sodium level above the normal range.

What manifestations are associated with hypernatremia?

Disorientation, hallucinations, agitation, restlessness, confusion, seizures, lethargy, tachycardia, dry mucous membranes, flushed skin, low-grade fever, and thirst.

What mnemonic can help remember hypernatremia manifestations?

SALT: Skin flushed, Agitation, Low-grade fever, Thirst.

What treatment is listed for hypernatremia?

Fluid replacement, ½ NS, and treatment of the underlying cause.

What is hyponatremia?

A sodium level below the normal range.

What manifestations are associated with hyponatremia?

Headache, lethargy, confusion, convulsions, nausea/vomiting, and coma.

What treatments are listed for hyponatremia?

Fluid restriction and oral sodium supplementation, depending on the cause/severity.

Where is potassium primarily located?

Inside cells in the ICF.

What are important functions of potassium?

Regulates cellular osmotic pressure and acid-base balance and assists with nerve impulse transmission and muscle function.

Why are potassium abnormalities especially dangerous?

They can cause serious cardiac dysrhythmias.

What is hyperkalemia?

Potassium above the normal range.

What manifestations are listed for hyperkalemia?

Muscle cramps, paresthesias progressing to weakness, abdominal cramping, dysrhythmias, and a widened QRS complex.

What medication is used to help treat hyperkalemia?

Kayexalate.

What is Kayexalate used for?

To help treat hyperkalemia by removing potassium.

What additional emergent treatments for hyperkalemia are listed?

IV calcium gluconate, IV sodium bicarbonate, IV regular insulin with hypertonic dextrose, beta₂ agonists, and dialysis.

What is hypokalemia?

Potassium below the normal range.

What manifestations are associated with hypokalemia?

Weakness, lethargy, hyporeflexia, nausea/vomiting, constipation, and ECG changes such as ST depression.

How can hypokalemia be treated?

Increase dietary potassium or provide potassium supplementation.

What is K-Dur?

An oral potassium chloride supplement used to replace potassium.

What regulates calcium according to the course material?

Primarily the parathyroid and thyroid.

What are major functions of calcium?

Blood clotting, neuromuscular excitability, and formation of bones and teeth.

What is hypocalcemia?

A calcium level below normal.

What are classic manifestations of hypocalcemia?

Tetany, circumoral numbness, paresthesias, hyperactive DTRs, seizures, and positive Chvostek and Trousseau signs.

What is Chvostek's sign associated with?

Hypocalcemia/neuromuscular irritability.

What is Trousseau's sign associated with?

Hypocalcemia/neuromuscular irritability.

What are causes of hypocalcemia?

Hypoparathyroidism, malabsorption, osteoporosis, pancreatitis, alkalosis, citrated blood transfusion, kidney injury, medications, and vitamin D deficiency.

What is used for emergent treatment of hypocalcemia?

IV calcium gluconate.

What oral supplements may be used for hypocalcemia?

Calcium and vitamin D.

Why is vitamin D important for calcium management?

Vitamin D supplementation is paired with calcium replacement in the management of hypocalcemia.

What is hypercalcemia?

A calcium level above normal.

What manifestations are associated with hypercalcemia?

Polyuria, thirst, muscle weakness, nausea, abdominal cramps, severe constipation, bone pain, ECG changes, and dysrhythmias.

What treatments are listed for hypercalcemia?

Treat the cause, IV fluids, furosemide, phosphates, calcitonin, bisphosphonates, increased mobility, fluids, and dietary management.

What is TUMS in relation to this competency?

TUMS contains calcium carbonate and can serve as a calcium-containing supplement/antacid.

What is hypomagnesemia?

Magnesium below the normal range.

What electrolyte abnormalities are commonly associated with hypomagnesemia?

Hypokalemia and hypocalcemia.

What causes of hypomagnesemia are listed?

Alcoholism, GI losses, magnesium-deficient enteral/parenteral feeding, medications, and rapid administration of citrated blood.

What manifestations occur with hypomagnesemia?

Neuromuscular irritability, muscle weakness, tremors, Chvostek/Trousseau signs, ECG changes, and dysrhythmias.

What happens to reflexes with hypomagnesemia?

They can become increased/hyperactive.

What treatments are used for hypomagnesemia?

IV magnesium sulfate or oral magnesium, depending on severity.

What nursing considerations are important with IV magnesium sulfate?

Use an infusion pump and monitor vital signs and urine output.

What is magnesium oxide (Mag oxide) used for?

Oral magnesium replacement.

What is hypermagnesemia?

Magnesium above the normal range.

Why is hypermagnesemia relatively uncommon?

Because functioning kidneys efficiently excrete magnesium.

What are causes of hypermagnesemia?

Kidney injury, DKA, excessive magnesium administration, and extensive soft-tissue injury.

What happens to deep tendon reflexes in hypermagnesemia?

They become decreased/hypoactive.

What other manifestations can occur with hypermagnesemia?

Drowsiness, muscle weakness, depressed respirations, ECG changes, dysrhythmias, and cardiac arrest.

What treatments are listed for hypermagnesemia?

IV calcium gluconate, hemodialysis, loop diuretics, sodium chloride, LR, and avoiding magnesium-containing medications.

What is an easy way to compare hypo- and hypermagnesemia?

Low Mg = increased neuromuscular excitability; high Mg = depressed neuromuscular activity.

What is the normal phosphorus level?

2.5-4.5 mg/dL.

What is hypophosphatemia?

Phosphorus below 2.5 mg/dL.

What causes of hypophosphatemia are listed?

Alcoholism, refeeding after starvation, respiratory alkalosis/hyperventilation, DKA, major burns, hyperparathyroidism, diarrhea, vitamin D deficiency, and certain medications.

What manifestations can occur with hypophosphatemia?

Confusion, muscle weakness, tissue hypoxia, muscle/bone pain, neurologic symptoms, and increased susceptibility to infection.

How is hypophosphatemia treated?

Oral or IV phosphorus replacement.

What is potassium phosphate used for?

To provide phosphate replacement; it also contains potassium.

What is hyperphosphatemia?

Phosphorus above 4.5 mg/dL.

What causes hyperphosphatemia?

Kidney injury, excess phosphorus, excess vitamin D, acidosis, hypoparathyroidism, and chemotherapy.

Why can hyperphosphatemia produce manifestations of hypocalcemia?

Its manifestations often occur because of associated hypocalcemia.

What is the normal chloride level?

97-107 mEq/L.

What is hypochloremia?

Chloride below 97 mEq/L.

What causes hypochloremia?

Addison disease, decreased chloride intake, GI losses, DKA, excessive sweating, fever, burns, medications, and metabolic alkalosis.

What manifestations can occur with hypochloremia?

Agitation, irritability, weakness, muscle hyperexcitability, dysrhythmias, seizures, and coma.

How can hypochloremia be treated?

Chloride replacement such as IV normal saline or 0.45% NS, depending on the clinical situation.

What is hyperchloremia?

Chloride above 107 mEq/L.

What causes hyperchloremia?

Excess sodium chloride infusions with water loss, head injury, hypernatremia, dehydration, severe diarrhea, respiratory alkalosis, metabolic acidosis, hyperparathyroidism, and medications.

What manifestations can occur with hyperchloremia?

Tachypnea, lethargy, weakness, rapid deep respirations, hypertension, and cognitive changes.