Antimicrobials · First-Generation Cephalosporins
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Cefazolin is a first-generation cephalosporin that provides excellent coverage against Gram-positive cocci, specifically Staphylococcus aureus and Streptococcus species.
Cefazolin is the prophylactic antibiotic of choice for most clean surgical procedures to prevent surgical site infections.
Cefazolin is the preferred treatment for methicillin-susceptible Staphylococcus aureus (MSSA) infections, including skin and soft tissue infections and bacteremia.
Cefazolin exhibits bactericidal activity by binding to penicillin-binding proteins (PBPs), thereby inhibiting bacterial cell wall synthesis.
Cefazolin does not provide reliable coverage against methicillin-resistant Staphylococcus aureus (MRSA), Enterococcus, or atypical pathogens.
Cefazolin is a safe alternative for patients with a non-IgE-mediated penicillin allergy, such as a mild rash, but should be avoided in patients with a history of anaphylaxis or urticaria to penicillins.
Cefazolin is primarily excreted via the kidneys, necessitating dosage adjustments in patients with significant renal impairment.
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A 55-year-old male is scheduled for an elective total hip arthroplasty. He has no known drug allergies and a past medical history significant for hypertension. His physical examination is unremarkable, and his preoperative laboratory studies are within normal limits. The surgical team intends to administer prophylactic antibiotics 60 minutes prior to the initial incision. The patient is currently afebrile with stable vital signs.
Which of the following is the most appropriate prophylactic antibiotic for this patient?
Cefazolin
Cefazolin is the gold standard for surgical prophylaxis in clean procedures like orthopedic surgery due to its efficacy against skin flora, specifically MSSA, testing Bet #2.
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Classification
First-generation cephalosporin; beta-lactam antibiotic.
Indications
Surgical prophylaxis and MSSA skin/soft tissue infections.
Mechanism of Action
Inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs).
Side Effects
Hypersensitivity reactions; anaphylaxis; C. difficile-associated diarrhea.
Contraindications / Monitoring
History of severe anaphylaxis to beta-lactams. Monitor renal function.
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