Surgical Site Infection Medical Slides

Present the WHO/CDC evidence-based bundle: (1) Antibiotic prophylaxis — within 60 minutes before incision (120 min for vancomycin/fluoroquinolones), weight-based dosing, redose at 2× half-life during prolonged cases, discontinue within 24 hours post-op (no benefit to extended prophylaxis). (2) Skin preparation — chlorhexidine-alcohol preferred over povidone-iodine (JAMA 2010, Darouiche). (3) Normothermia — forced-air warming, target temp ≥36°C (hypothermia impairs neutrophil function). (4) Glycemic control — target glucose <200 mg/dL perioperatively (NICE-SUGAR-informed). (5) Supplemental oxygen — FiO2 0.80 intraoperatively (WHO recommendation, moderate evidence). Bundle compliance >95% reduces SSI by 40-60%.

Present the SCIP/ASHP guidelines: Clean procedures (cardiac, orthopedic, hernia, breast) — cefazolin 2 g IV (3 g if >120 kg). Clean-contaminated GI — cefazolin + metronidazole (colorectal) or cefoxitin alone. Clean-contaminated GU/GYN — cefazolin. Biliary — cefazolin (add metronidazole if bile duct obstruction). MRSA risk (known colonization, cardiac/orthopedic implant at MRSA-prevalent institution) — add vancomycin. Beta-lactam allergy — clindamycin + gentamicin or aztreonam. Timing: <60 minutes pre-incision for cephalosporins (the single most impactful intervention), <120 minutes for vancomycin. Redosing: cefazolin every 4 hours for cases >4 hours. Stop within 24 hours — no evidence for extended prophylaxis.

Present the management algorithm: Superficial SSI — open wound, express purulence, saline irrigation, pack wound open for healing by secondary intention or delayed primary closure. Antibiotics usually NOT required (unless surrounding cellulitis >2 cm). Deep incisional SSI — open wound, debride necrotic tissue, culture, targeted antibiotics, negative pressure wound therapy (VAC) accelerates granulation. CT imaging to rule out deeper collection. Organ/space SSI (e.g., intra-abdominal abscess) — percutaneous CT-guided drainage (preferred if accessible and loculated), IV antibiotics, repeat imaging to confirm resolution. Surgical washout if percutaneous drainage fails or peritonitis develops. Mesh infection after hernia repair may require mesh explantation.