Normal ranges
What is the normal range for serum sodium (Na⁺)?
135–145 mEq/L
Which electrolyte imbalance causes muscle cramps and confusion?
Hyponatremia (low sodium)
Which lab value should be monitored closely with diuretic therapy?
Potassium
What is the priority nursing intervention for hyperkalemia?
Monitor cardiac rhythm and prepare to administer insulin with glucose or calcium gluconate
What is a common cause of hyperkalemia?
Renal failure or potassium-sparing diuretics
What is the normal range for serum potassium (K⁺)?
3.5–5.0 mEq/L
Which imbalance can lead to cardiac arrhythmias and muscle weakness?
Hypokalemia (low potassium)
If a patient has low sodium, what fluid imbalance might also occur?
Fluid overload or hyponatremia due to water retention
Which foods should you encourage for a patient with hypokalemia?
Bananas, oranges, potatoes, spinach, avocados
What condition can lead to hyponatremia?
Excessive water intake or SIADH
What is the normal range for serum calcium (Ca²⁺)?
8.5–10.5 mg/dL
Which condition is associated with positive Chvostek’s and Trousseau’s signs?
Hypocalcemia (low calcium)
What happens to serum calcium levels when phosphate levels are high?
Calcium decreases (inverse relationship)
What should the nurse monitor for when administering IV potassium?
Cardiac rhythm, infusion rate (NEVER IV push), and site for phlebitis
Which type of diuretic commonly causes hypokalemia?
Loop diuretics like furosemide
What is the normal range for magnesium (Mg²⁺)?
1.5–2.5 mEq/L
Tremors, seizures, and increased deep tendon reflexes may indicate low levels of what electrolyte?
Magnesium (Hypomagnesemia)
Which lab test confirms hypomagnesemia?
Serum magnesium < 1.5 mEq/L
Which medication might be used to lower elevated calcium levels?
Calcitonin or bisphosphonates
What can cause hypercalcemia in cancer patients?
Bone metastases or paraneoplastic syndrome
What is the normal range for phosphate (PO₄³⁻)?
2.5–4.5 mg/dL
What symptoms would you expect in hyperphosphatemia?
Muscle cramps, tetany, soft tissue calcification
A patient has a sodium of 128, potassium of 3.2, and calcium of 7.9. What is the priority?
Address hypokalemia (risk of cardiac issues)
A patient is on magnesium sulfate. What is the priority nursing action?
Monitor for decreased reflexes and respiratory depression
Which gastrointestinal issue can cause hypomagnesemia?
Chronic diarrhea or malabsorption syndromes