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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Name: ____________________   Date: ____________

1.Easy

A raised procalcitonin level most strongly suggests:

  1. AAn allergic reaction
  2. BA viral common cold
  3. CIron-deficiency anemia
  4. DA bacterial infection
2.Easy

Which sample is commonly used to screen a patient for MRSA carriage on admission?

  1. AA swab from the front of the nose
  2. BA blood culture from one arm
  3. CA clean-catch midstream urine sample
  4. DA sample of stool sent for culture
3.Easy

What is the effect of insulin on serum potassium?

  1. AIt has no effect on potassium in any amount
  2. BIt makes the kidneys keep more potassium in the blood
  3. CIt moves potassium into cells, lowering the serum level
  4. DIt moves potassium out of cells, raising the serum level
4.Medium

Which blood collection practice helps prevent hemolysis of the sample?

  1. AUsing the smallest needle available for every patient
  2. BForcing blood quickly through a needle into the tube
  3. CGently inverting the tubes instead of shaking them
  4. DLeaving the tourniquet on for at least 3 minutes
5.Medium

A patient with iron-deficiency anemia started oral iron. Which result is usually the earliest sign that treatment is working?

  1. AA fall in the mean cell volume (MCV)
  2. BA fall in the white cell count
  3. CA rise in the platelet count
  4. DA rise in the reticulocyte count
6.Medium

A 55-year-old has a positive fecal immunochemical test (FIT) during routine screening. What is the usual next step?

  1. ARepeat the test in 10 years
  2. BReferral for colonoscopy
  3. CStart an iron supplement only
  4. DNo action if there are no symptoms
7.Hard

A patient has a sodium of 150 mEq/L, a glucose of 180 mg/dL and a BUN of 28 mg/dL. Using the formula 2 × Na + glucose/18 + BUN/2.8, what is the calculated serum osmolality?

  1. AAbout 285 mOsm/kg, which is normal
  2. BAbout 358 mOsm/kg, which is high
  3. CAbout 320 mOsm/kg, which is high
  4. DAbout 300 mOsm/kg, which is normal
8.Hard

A patient taking apixaban asks why they do not need regular INR tests like their neighbor on warfarin. What is the best explanation?

  1. AThe INR is checked secretly together with the other routine blood tests
  2. BApixaban does not actually thin the blood
  3. CApixaban is monitored with an aPTT every day instead
  4. DIts effect is predictable, so routine clotting tests are not needed

Answer key

  1. 1. D · A bacterial infection
  2. 2. A · A swab from the front of the nose
  3. 3. C · It moves potassium into cells, lowering the serum level
  4. 4. C · Gently inverting the tubes instead of shaking them
  5. 5. D · A rise in the reticulocyte count
  6. 6. B · Referral for colonoscopy
  7. 7. C · About 320 mOsm/kg, which is high
  8. 8. D · Its effect is predictable, so routine clotting tests are not needed

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