Antimicrobial prophylaxis in general surgery.

When used appropriately, antimicrobial prophylaxis is highly beneficial and cost effective. Antibiotics are not indicated for "clean procedures" such as hernia and breast surgery. A single preoperative dose will suffice, followed by an intraoperative dose if the operation takes more than 3 hours. For vascular (prosthesis or groin wound), head and neck (pharynx entered), thoracic (gastrointestinal or respiratory entrance) and high-risk gastroduodenal and biliary procedures, cefazolin, 1 g intravenously, is indicated. For procedures involving small intestine, appendix or penetrating abdominal trauma, cefoxitin or cefotetan, 2 g intravenously, is indicated. For colorectal procedures, either oral neomycin plus erythromycin or intravenous aminoglycoside plus clindamycin (or metronidazole) are effective. If valvular heart disease is present, endocarditis prophylaxis should be administered.