What is the recommended management for a surgical wound infection?

Management of Surgical Wound Infection

The primary treatment for surgical wound infections is suture removal plus incision and drainage, with systemic antibiotics reserved only for cases with significant systemic signs of infection (fever >38.5°C, tachycardia >110 bpm, WBC >12,000/μL, or erythema extending >5 cm from wound edge) or in immunocompromised patients. 1

Initial Assessment and Surgical Management

All surgical site infections require prompt surgical intervention as the cornerstone of treatment:

• Remove sutures and perform incision and drainage immediately for all surgical site infections, regardless of severity 1, 2
• Open the wound widely to allow adequate drainage and debridement of infected tissue 1
• Irrigate the wound thoroughly during the drainage procedure 1
• If fascial disruption is suspected, drainage must always be performed 1
• Obtain Gram stain and culture of purulent material to guide targeted antimicrobial therapy 2

When to Add Systemic Antibiotics

Antibiotics are NOT routinely indicated after adequate drainage. 1, 2 However, add systemic antimicrobial therapy when ANY of the following are present:

• Temperature >38.5°C 1
• Heart rate >110 beats/minute 1
• White blood cell count >12,000/μL 1
• Erythema and induration extending >5 cm from the wound edge 1
• Signs of systemic inflammatory response syndrome (SIRS) 1
• Altered mental status or hemodynamic instability 1
• Immunocompromised patient 1
• Hypotension or oliguria 1

Antibiotic Selection Based on Surgical Site

The choice of antibiotic depends critically on the anatomical location and type of surgery:

For Trunk or Extremity Surgery (Away from Axilla/Perineum)

Target: Staphylococcus aureus (most common pathogen) 1

• First-line: Cefazolin 0.5-1 g IV every 8 hours OR oxacillin/nafcillin 2 g IV every 6 hours 1
• Oral option: Cephalexin 500 mg every 6 hours 1
• If MRSA suspected or confirmed: Vancomycin 15 mg/kg IV every 12 hours 1, 2
• Alternative for MRSA: Linezolid, daptomycin, telavancin, or ceftaroline 2

For Intestinal or Genitourinary Tract Surgery

Target: Mixed aerobic-anaerobic flora, gram-negative bacteria 1

Single-drug regimens:

• Piperacillin-tazobactam 3.375 g every 6 hours or 4.5 g every 8 hours IV 1
• Ertapenem 1 g every 24 hours IV 1
• Meropenem 1 g every 8 hours IV 1
• Imipenem-cilastatin 500 mg every 6 hours IV 1

Combination regimens:

• Ceftriaxone 1 g every 24 hours + metronidazole 500 mg every 8 hours IV 1, 2
• Ciprofloxacin 400 mg IV every 12 hours (or 750 mg PO every 12 hours) + metronidazole 500 mg every 8 hours IV 1, 2
• Levofloxacin 750 mg IV every 24 hours + metronidazole 500 mg every 8 hours IV 1, 2

For Axilla or Perineum Surgery

Target: Mixed skin organisms and enteric bacteria 1

• Metronidazole 500 mg every 8 hours IV PLUS one of the following: 1
  • Ciprofloxacin 400 mg IV every 12 hours or 750 mg PO every 12 hours 1
  • Levofloxacin 750 mg every 24 hours IV 1
  • Ceftriaxone 1 g every 24 hours 1

Duration of Antibiotic Therapy

• Standard duration: 5-7 days after adequate drainage is typically sufficient 2
• Superficial infections that have been opened: Can usually be managed without antibiotics if no systemic signs present 1
• Longer courses may be needed for complex infections or immunocompromised patients 2

Risk Factors for MRSA Requiring Empiric Coverage

Consider empiric MRSA coverage if the patient has: 1

• Residence in long-stay care facility 1
• Hospitalization within preceding 30 days 1
• Charlson score >5 points 1
• Recent antibiotic therapy with beta-lactams, carbapenems, or quinolones (within 30 days) 1
• Age ≥75 years 1
• Current hospitalization >16 days 1
• Surgery with prosthesis implantation 1

Adjunctive Measures

• Elevate the affected area to reduce edema 1
• Treat predisposing factors: edema, obesity, eczema, venous insufficiency 1
• Consider negative pressure-assisted wound management for complex wounds 1
• Tetanus prophylaxis: Administer tetanus toxoid if not vaccinated within 10 years; prefer Tdap over Td if not previously given 1

When to Hospitalize

Hospitalization is recommended for: 1

• Concern for deeper or necrotizing infection 1
• Poor adherence to therapy 1
• Severely immunocompromised patient 1
• Outpatient treatment failing 1
• Signs of systemic toxicity 1

Prevention of Recurrent Infections

For patients with 3-4 episodes per year despite treating predisposing factors: 1, 2

• Consider prophylactic antibiotics: oral penicillin or erythromycin twice daily for 4-52 weeks 1, 2
• Alternative: intramuscular benzathine penicillin every 2-4 weeks 1, 2
• Continue prophylaxis as long as predisposing factors persist 1

Critical Pitfalls to Avoid

• Do NOT rely on antibiotics alone without surgical drainage when an abscess is present 1, 2
• Do NOT routinely give antibiotics for uncomplicated surgical site infections after adequate drainage 1, 2
• Do NOT continue antibiotics beyond 7 days for most surgical site infections 2
• Do NOT use narrow-spectrum agents for infections involving the gastrointestinal tract, axilla, or perineum—these require anaerobic coverage 1, 2
• Do NOT forget to check for fascial involvement, which mandates immediate drainage 1