Lab values & electrolytes worksheet with answers

Free printable Lab values & electrolytes worksheet: 8 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

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1.Easy

Why is "free T4" often measured rather than total T4?

  1. AThe free form is the only form made by the gland
  2. BThe free form is the unbound, active hormone
  3. CThe free form is the form excreted in urine
  4. DThe free form is stored inside the pituitary
2.Easy

What is the main effect of parathyroid hormone (PTH) on serum calcium?

  1. AIt only changes urine calcium
  2. BIt has no effect on calcium
  3. CIt raises serum calcium
  4. DIt lowers serum calcium
3.Easy

Which blood marker is the most specific for injury to the heart muscle?

  1. ACardiac troponin
  2. BSerum myoglobin
  3. CTotal creatine kinase
  4. DLactate dehydrogenase
4.Medium

A patient on warfarin for atrial fibrillation has a target INR of 2.0–3.0. How does the usual target for a patient with a mechanical mitral valve compare?

  1. AMuch higher, about 5.0–6.0
  2. BThe same, 2.0–3.0
  3. CHigher, about 2.5–3.5
  4. DLower, about 1.0–1.5
5.Medium

A patient taking furosemide has a potassium of 2.9 mEq/L. Which finding would the nurse expect?

  1. ATall, peaked T waves on the ECG
  2. BTingling around the mouth with a positive Chvostek’s sign
  3. CMuscle weakness and leg cramps
  4. DDiarrhea and abdominal cramping from overactive bowels
6.Medium

A patient with hyperkalemia is prescribed an oral potassium binder such as patiromer or sodium zirconium cyclosilicate. How does this drug lower potassium?

  1. AIt binds potassium in the gut so it leaves in the stool
  2. BIt moves potassium into cells in the next few minutes
  3. CIt stops the kidneys from absorbing water in the tubules
  4. DIt protects the heart muscle against high potassium levels
7.Hard

An 82-year-old woman without a catheter has a urine culture growing bacteria, but no fever, urinary symptoms or change in mental state. What is the best interpretation?

  1. AContamination, so the culture must be repeated every week
  2. BPyelonephritis, which needs admission and IV fluids today
  3. CAsymptomatic bacteriuria, usually not treated with antibiotics
  4. DA urinary tract infection that needs urgent IV antibiotics
8.Hard

A patient with a stable INR on warfarin starts rifampin (rifampicin) for tuberculosis. Two weeks later the INR is 1.3. What is the most likely explanation?

  1. ARifampin contains a lot of vitamin K
  2. BTuberculosis causes the INR to fall
  3. CRifampin raises the INR, so it is wrong
  4. DRifampin speeds up warfarin metabolism

Answer key

  1. 1. B · The free form is the unbound, active hormone
  2. 2. C · It raises serum calcium
  3. 3. A · Cardiac troponin
  4. 4. C · Higher, about 2.5–3.5
  5. 5. C · Muscle weakness and leg cramps
  6. 6. A · It binds potassium in the gut so it leaves in the stool
  7. 7. C · Asymptomatic bacteriuria, usually not treated with antibiotics
  8. 8. D · Rifampin speeds up warfarin metabolism

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