In arthroplasty, prophylactic antibiotics are typically given within 60 minutes of incision and continued postoperatively for how long?

• A. 12 hours
• B. 48 hours
• C. 24 hours
• D. 72 hours

Answer: (C)

Prophylactic antibiotics in arthroplasty aim to prevent surgical site infection by ensuring the drug is at effective levels during the operation and in the immediate postoperative period. Administering the antibiotic within about 60 minutes before incision ensures tissue concentrations are high right when the incision is made, and continuing the course afterward covers the early post-op window when infections are most likely to begin.

The typical duration is 24 hours postoperatively. This timing balances effectiveness with minimizing risks. Extending antibiotics beyond 24 hours does not reliably reduce infection rates in clean orthopedic procedures and raises the chance of adverse effects, including antibiotic resistance and C. difficile infection. Shortening to 12 hours could leave tissue levels subtherapeutic after the immediate perioperative period, potentially narrowing protection.

So, 24 hours post-op is the standard duration for prophylactic antibiotics in arthroplasty.