Fluid & Electrolyte Balance Flashcards
7 cards from real MSNCB practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Fluid & Electrolyte Balance flashcards as text
A patient's ABG shows pH 7.28, PaCO2 38 mmHg, HCO3 16 mEq/L. Which acid-base disturbance does this indicate?
Answer: Metabolic acidosis
A pH below 7.35 with low bicarbonate (<22 mEq/L) and normal PaCO2 indicates uncompensated metabolic acidosis.
Which clinical finding is most associated with hypocalcemia?
Answer: Trousseau's sign
Trousseau's sign — carpopedal spasm triggered by BP cuff inflation — is a classic manifestation of hypocalcemia due to increased neuromuscular excitability.
A patient receiving prolonged total parenteral nutrition (TPN) is at risk for which electrolyte imbalance that can cause respiratory muscle weakness?
Answer: Hypophosphatemia
Refeeding syndrome with aggressive TPN can cause hypophosphatemia, which impairs ATP production and can result in severe respiratory muscle weakness or failure.
Which symptom is characteristic of hypermagnesemia?
Answer: Loss of deep tendon reflexes
Hypermagnesemia suppresses neuromuscular transmission, and loss of deep tendon reflexes is an early, clinically significant sign of magnesium toxicity.
A patient has a serum potassium of 6.2 mEq/L. Which ECG change would the nurse most likely observe?
Answer: Peaked (tall, narrow) T waves
Hyperkalemia classically produces tall, peaked, narrow T waves on ECG, representing one of the earliest electrocardiographic signs of elevated potassium.
Which set of findings is most consistent with SIADH (Syndrome of Inappropriate Antidiuretic Hormone)?
Answer: Hyponatremia with concentrated urine
SIADH causes excessive ADH secretion, leading to water retention, dilutional hyponatremia, and paradoxically concentrated urine (elevated urine osmolality).
A nurse is preparing to administer potassium chloride IV to a patient with hypokalemia. Which action is essential for patient safety?
Answer: Dilute and infuse at no more than 10–20 mEq/hour via infusion pump
IV potassium must always be diluted and administered slowly (≤10–20 mEq/hr) via a controlled infusion pump to prevent fatal cardiac arrhythmias from rapid potassium shifts.