<prompt> The best time period to give preoperative antibiotics :Within 1 hour prior to incisionWithin 6 hour prior to incisionJust before incisionJust before induction of anaesthesia  <response>: It is best to give antibiotics within 1 hour prior to surgical site incision. There is two exception to this rule i. Vancomycin should be given 2 hours prior ii. When tourniquet is used it should be given before inflation of tourniquet. The most common organisms implicatedas causes of surgical site infections include: staphylococcus aureus staphylococcusepidermidis aerobic streptococci anaerobic cocci 