Which antibiotic is paired with cefazolin for open fracture prophylaxis?

Which antibiotic is paired with cefazolin for open fracture prophylaxis?

• A. Amoxicillin-clavulanate
• B. Vancomycin
• C. Aminoglycoside
• D. Ceftriaxone

Answer: (C)

Open fractures carry a high risk of contamination from the environment, so prophylaxis needs to cover both skin flora and potential Gram-negative bacteria. Cefazolin effectively covers most Staphylococcus and Streptococcus species, addressing the skin flora, but it doesn’t reliably cover environmental Gram-negative organisms that can contaminate an open wound. Adding an aminoglycoside provides strong Gram-negative coverage, including common soil and gut bacteria, which helps prevent infection in these injuries. The other options don’t offer the same targeted combination: amoxicillin-clavulanate adds anaerobic coverage but isn’t the standard adjunct with cefazolin for open fractures; vancomycin is used mainly when MRSA risk or beta-lactam allergy is a concern; ceftriaxone covers some Gram-negatives but isn’t the routine partner to cefazolin for open fracture prophylaxis. Therefore, pairing cefazolin with an aminoglycoside best addresses the infection risks in open fractures.

Open fractures carry a high risk of contamination from the environment, so prophylaxis needs to cover both skin flora and potential Gram-negative bacteria. Cefazolin effectively covers most Staphylococcus and Streptococcus species, addressing the skin flora, but it doesn’t reliably cover environmental Gram-negative organisms that can contaminate an open wound. Adding an aminoglycoside provides strong Gram-negative coverage, including common soil and gut bacteria, which helps prevent infection in these injuries. The other options don’t offer the same targeted combination: amoxicillin-clavulanate adds anaerobic coverage but isn’t the standard adjunct with cefazolin for open fractures; vancomycin is used mainly when MRSA risk or beta-lactam allergy is a concern; ceftriaxone covers some Gram-negatives but isn’t the routine partner to cefazolin for open fracture prophylaxis. Therefore, pairing cefazolin with an aminoglycoside best addresses the infection risks in open fractures.