In this episode, I’ll discuss cefazolin underdosing and the risk of surgical site infection.
There has been a lack of solid outcome data in the literature to support recommendations for weight-based dosing of cefazolin to prevent surgical site infection in orthopedic patients. But recently researchers evaluated patients in New Zealand’s national, prospective, surveillance and quality improvement SSI Improvement Programme database to determine surgical site infection (SSI) rates by dose of cefazolin used for surgical prophylaxis after hip or knee arthroplasty.
Over 30,000 patients were analyzed. About one-third of patients weighing greater than 80 kg were underdosed, and about three-quarters weighing over 120 kg were underdosed. The odds ratio for SSI was 2.19 in patients who were underdosed, and this was statistically and clinically significant (95% confidence interval, 1.61-2.99; P < 0.0001).
This data provides outcomes data to support weight-based dosing of cefazolin. Patients undergoing hip or knee arthroplasty with a weight above 80 kg and those with a weight above 120 kg should receive cefazolin doses of 2 g and ≥3 g, respectively, to prevent SSI.
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Athat says
I want to ask u plz ..the dr give post hip and knee cefazolin 1 g tid up to 24 hrs …based on this u recommend to give 2 g tid ??? Even if the pt weight is around 60 ?
DN says
I dont think that’s what he’s saying.
120kg = 3g
Noha Hafez says
To my understanding the post op doses should be ancef 1gm q8h x 3 doses, since the two gram dose pre-op is based on the trials that had proven benefit due to higher concentration of the drug at cut time. For post-op doses, no need for higher concentration of the drug as there is no “open wound” that necessitates higher concentration.