Pharmacology Antibiotics #10

Question

The nurse is caring for a patient with bacterial pneumonia who is receiving gentamicin. Which laboratory value is most important to monitor by the nurse?

Answers

  1. Serum potassium.
    • Rationale:

      This answer is not correct because electrolyte monitoring, such as serum potassium levels, are not used to monitor aminoglycoside antibiotics, such as gentamicin. Because aminoglycoside antibiotics, like gentamicin, have a risk of nephrotoxicity, serum blood tests reflecting kidney function, such as creatinine and blood urea nitrogen (BUN), should be carefully monitored.

  2. Serum sodium.
    • Rationale:

      This answer is not correct because electrolyte monitoring, such as serum sodium levels, are not used to monitor aminoglycoside antibiotics, such as gentamicin. Because aminoglycoside antibiotics, like gentamicin, have a risk of nephrotoxicity, serum blood tests reflecting kidney function, such as creatinine and blood urea nitrogen (BUN), should be carefully monitored.

  3. Serum creatinine.
    • Rationale:

      This answer is correct because aminoglycoside antibiotics, like gentamicin, have a risk of nephrotoxicity. Therefore, serum blood tests which reflect kidney function, such as creatinine and blood urea nitrogen (BUN), should be carefully monitored. Creatinine levels > 1.3 mg/dL and BUN levels > 20 mg/dL should be reported to the health care provider, especially when the patient is being administered nephrotoxic medications, such as aminoglycoside antibiotics like gentamicin.

  4. Serum alkaline phosphatase (ALP).
    • Rationale:

      This answer is not correct because serum alkaline phosphatase (ALP) is not a priority lab to monitor due to the fact that hepatotoxicity is not generally associated with aminoglycosides. Nevertheless, nephrotoxicity is associated with aminoglycoside use, so the creatinine is a priority lab to be monitored.

Overview

Aminoglycoside antibiotics, like gentamicin, have a risk of nephrotoxicity, therefore serum creatinine should be monitored carefully in the patient taking the medication.

Explanation

Learning Outcomes

Aminoglycoside antibiotics, like gentamicin, have a risk of nephrotoxicity. Kidney damage associated with aminoglycosides include the risk for tubular necrosis with decreased glomerular filtration. Therefore, serum blood tests which reflect kidney function, such as creatinine and blood urea nitrogen (BUN), should be carefully monitored. Creatinine levels > 1.3 mg/dL and BUN levels > 20 mg/dL should be reported to the health care provider, especially when the patient is being administered nephrotoxic medications, such as aminoglycoside antibiotics like gentamicin.

Test Taking Tip

Creatinine is the most sensitive lab to reflect kidney function. Monitor it closely if nephrotoxicity is a side effect of a medication.

Video Rationale