IV Fluid & Electrolyte Balance 2 — Questions and Answers
Question 1: A patient's serum potassium is 6.2 mEq/L. Which IV fluid should be avoided?
- 0.9% Normal Saline
- Lactated Ringer's
- Potassium Chloride in D5W (Correct answer)
- 0.45% Half Normal Saline
Correct answer: Potassium Chloride in D5W
Administering potassium-containing IV fluids to a hyperkalemic patient worsens the dangerous electrolyte imbalance.
Question 2: Which finding is most consistent with fluid volume deficit (dehydration)?
- Bounding pulse
- Elevated CVP
- Decreased skin turgor (Correct answer)
- Periorbital edema
Correct answer: Decreased skin turgor
Decreased skin turgor is a classic sign of dehydration due to reduced interstitial fluid volume.
Question 3: A patient receiving a rapid infusion of 0.9% NS develops crackles in the lungs and an SpO2 drop. What complication has occurred?
- Hypoglycemia
- Air embolism
- Fluid overload (Correct answer)
- Phlebitis
Correct answer: Fluid overload
Pulmonary crackles and oxygen desaturation following rapid fluid infusion indicate fluid overload with pulmonary edema.
Question 4: Serum sodium is 128 mEq/L. How is this condition classified?
- Hypernatremia
- Hyponatremia (Correct answer)
- Normonatremia
- Pseudohyponatremia
Correct answer: Hyponatremia
Normal serum sodium is 135–145 mEq/L; a value of 128 mEq/L is below normal and classified as hyponatremia.
Question 5: Which IV solution is most appropriate to treat symptomatic hyponatremia?
- D5W
- 0.45% NS
- 3% Hypertonic Saline (Correct answer)
- Lactated Ringer's
Correct answer: 3% Hypertonic Saline
3% hypertonic saline raises serum sodium in patients with severe symptomatic hyponatremia.
Question 6: A patient with burns is at greatest risk for which fluid and electrolyte imbalance in the first 24 hours?
- Hypervolemia and hypernatremia
- Hypovolemia and hypokalemia (Correct answer)
- Hyperkalemia and metabolic alkalosis
- Hypocalcemia and hyponatremia
Correct answer: Hypovolemia and hypokalemia
Massive fluid and electrolyte loss through burned tissue causes hypovolemia and hypokalemia in the acute burn phase.
Question 7: Which electrolyte imbalance causes prolonged QT interval on ECG?
- Hypernatremia
- Hypercalcemia
- Hypomagnesemia (Correct answer)
- Hyperkalemia
Correct answer: Hypomagnesemia
Hypomagnesemia prolongs the QT interval and increases the risk of life-threatening arrhythmias such as torsades de pointes.
IV Fluid & Electrolyte Balance 2
A patient's serum potassium is 6.2 mEq/L.
Which IV fluid should be avoided?