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SUMMARY
The optimal time for administration of preoperative intravenous antibiotics is within 60 minutes before surgical incision; data suggests administration between 15 to 30 minutes before surgical incision may be best.

Except where explicitly stated, only a single preoperative dose is indicated.
Cephazolin dose for all adult patients is 2 grams IV, regardless of weight. Repeat the cephazolin dose intraoperatively if the procedure lasts more than 3 hours.

Check if preoperative Staphylococus aureus (including MRSA) screening was performed to determine if a patient requires a glycopeptide (teicoplanin) for MRSA carriage.

Teicoplanin is now the glycopeptide of choice because of its simple dosing regimen (once only over 5 minutes) compared with vancomycin’s (see Table 3, page 6). This should facilitate effective prophylaxis. However, teicoplanin costs $36 for a 400mg ampoule while vancomycin costs only $2.06 for a 500mg ampoule, so vancomycin remains in this guideline as an alternative.

For patients already receiving regular doses of β-lactam antibiotics with activity against likely intraoperative pathogens, recommended prophylaxis may be omitted if it is likely that a steady state concentration above the relevant minimal inhibitory concentration has been reached.