Lab values & electrolytes worksheet with answers

Which substance contributes most to normal serum osmolality?

1. AGlucose in plasma
2. BUrea (from BUN)
3. CSodium and its anions
4. DPlasma albumin

Which ECG change is linked to hypercalcemia?

1. AProminent U waves
2. BA prolonged QT interval
3. CA shortened QT interval
4. DTall, peaked T waves

What is the usual target INR for a patient taking warfarin for a deep vein thrombosis?

1. A2.0–3.0
2. B4.0–5.0
3. C1.0–1.5
4. D0.8–1.2

A patient with hyponatremia from SIADH starts tolvaptan. Why is the serum sodium checked frequently in the first day?

1. AThe sodium can rise too quickly
2. BThe sodium always falls further
3. CThe drug causes severe hyperkalemia
4. DThe drug lowers blood glucose sharply

A patient on a heparin infusion has blood in the urine and an aPTT far above the target. The nurse stops the infusion and informs the provider. Which antidote should the nurse anticipate?

1. ACalcium gluconate
2. BProtamine sulfate
3. CVitamin K (phytonadione)
4. DNaloxone

A patient had a total gastrectomy. Which long-term therapy is needed to prevent anemia?

1. ALifelong oral folic acid tablets only
2. BWeekly doses of oral vitamin K tablets
3. CMonthly transfusions of red blood cells
4. DLifelong vitamin B₁₂ replacement

A patient’s total calcium is 7.9 mg/dL (2.0 mmol/L), with an albumin of 2.4 g/dL (24 g/L) and no symptoms. Which test would best clarify whether true hypocalcemia is present?

1. AAn ionized calcium
2. BA urine specific gravity
3. CAn HbA1c
4. DA serum sodium

A patient stopped long-term prednisone suddenly a week ago. Now: blood pressure 78/46 mm Hg, sodium 128 mEq/L, potassium 4.6 mEq/L, glucose 58 mg/dL (3.2 mmol/L). Which condition is most likely?

1. APrimary hyperaldosteronism (Conn syndrome)
2. BAcute adrenal insufficiency (adrenal crisis)
3. CCushing syndrome from steroid excess
4. DSyndrome of inappropriate ADH (SIADH)