What are the guidelines for surgical antibiotic prophylaxis?

Guidelines for Surgical Antibiotic Prophylaxis

Surgical antibiotic prophylaxis (SAP) should be administered as a single dose within 30-60 minutes before surgical incision, with specific antibiotics targeted to likely pathogens, and generally should not be continued beyond the operative period. 1

Core Principles of Surgical Antibiotic Prophylaxis

• SAP should be administered for procedures with high risk of postoperative surgical site infection (SSI) or when foreign materials are implanted 1
• Antibiotics should target the most likely contaminants - typically gram-positive skin commensals or normal flora colonizing incised mucosae 1
• Administration timing is critical: within 120 minutes before incision, but ideally 30-60 minutes before incision for most antibiotics 1
• For vancomycin, infusion should begin early enough to be completed 30 minutes before the procedure 1
• A single preoperative dose is sufficient for most procedures 1, 2
• Redosing is required for procedures lasting longer than 2-4 hours (depending on the antibiotic's half-life) or with significant blood loss (>1.5L) 1
• There is no evidence supporting postoperative antibiotic prophylaxis for most procedures 1

Antibiotic Selection by Procedure Type

Orthopedic Surgery 1

• Joint prosthesis/implants: Cefazolin 2g IV (1g if >4h), cefamandole 1.5g IV (0.75g if >2h), or cefuroxime 1.5g IV (0.75g if >2h)
• Allergy alternatives: Clindamycin 900mg IV or vancomycin 30mg/kg (120-min infusion)
• Arthroscopy without implant: No prophylaxis needed

Neurosurgery 1

• Craniotomy/CSF shunt: Cefazolin 2g IV (1g if >4h)
• Allergy alternative: Vancomycin 30mg/kg (120-min infusion)
• External CSF shunt: No prophylaxis needed

Digestive Surgery 1

• Colorectal surgery: Cefoxitin 2g IV + metronidazole 1g IV
• Biliary tract/gastroduodenal surgery: Cefazolin 2g IV, cefuroxime 1.5g IV, or cefamandole 1.5g IV
• Hernia with prosthetic plate: Cefazolin 2g IV (1g if >4h)

Obstetrics & Gynecology 1

• Cesarean section: Cefazolin 2g IV (single dose)
• Hysterectomy: Cefazolin 2g IV, cefamandole 1.5g IV, or cefuroxime 1.5g IV

Bariatric Surgery 1

• Gastric band: Cefazolin 4g IV (30-min infusion)
• Gastric bypass/sleeve gastrectomy: Cefoxitin 4g IV (30-min infusion)

Special Considerations

Dosing for Obese Patients

• Patients ≥120kg require higher doses of antibiotics 1
• For bariatric surgery: cefazolin 4g (30-min infusion) or cefuroxime 3g (30-min infusion) 1
• Doses should be calculated based on actual weight 1

Vancomycin Indications 1

• Allergy to beta-lactams
• Suspected or proven colonization by methicillin-resistant staphylococci
• Reoperation in a patient hospitalized in a unit with MRSA ecology
• Previous antibiotic therapy
• Vancomycin infusion must be completed at least 30 minutes before incision 1

Duration Exceptions

• Most procedures: Single dose or limited to operative period 1, 2
• Some cardiac and vascular surgeries: Up to 24 hours 1
• Open fractures: 24-48 hours depending on severity 1
• Cranio-cerebral wounds: Up to 48 hours 1

Common Pitfalls to Avoid

• Prolonged prophylaxis: Extending antibiotics beyond 24-48 hours increases risk of antimicrobial resistance without reducing SSI rates 1, 3
• Delayed administration: Failure to administer antibiotics within 60 minutes before incision reduces effectiveness 1, 2
• Inappropriate antibiotic selection: Using broad-spectrum antibiotics when narrower options would suffice 1
• Failure to redose: Not providing additional doses during prolonged procedures 1
• Overlooking non-antibiotic measures: Antibiotics alone cannot prevent SSIs; proper infection prevention practices, surgical technique, and patient optimization are essential 1

Additional Prevention Strategies 1

• Proper hand hygiene practices
• Meticulous surgical techniques and minimization of tissue trauma
• Appropriate hospital and operating room environments
• Proper instrument sterilization processes
• Perioperative optimization of patient risk factors
• Appropriate management of surgical wounds
• Perioperative temperature, fluid, and oxygenation management
• Targeted glycemic control

Each institution should develop specific guidelines for surgical prophylaxis based on local patterns of antimicrobial resistance and available resources 1.