In a 60-year-old man 6 days after open appendectomy with a red, swollen, tender surgical incision, what is the most appropriate next step in management?

Management of Postoperative Wound Infection After Open Appendectomy

Open the wound immediately—this is a surgical site infection (SSI) requiring incision and drainage, which is the primary and most effective treatment. 1, 2

Why Opening the Wound is the Correct Answer

The clinical presentation of a red, swollen, and tender wound 6 days post-open appendectomy meets CDC criteria for a superficial SSI, and the primary therapy for SSI is incision opening and drainage, not antibiotics or imaging. 2 This approach is supported by multiple guidelines:

• Incision and drainage is the definitive treatment for postoperative wound infections, and studies demonstrate no clinical benefit from antibiotics when used without drainage. 2
• The timing (day 6 postoperatively) is classic for SSI development, as most surgical site infections manifest within the first week after surgery. 3, 4
• Open appendectomy carries a significantly higher SSI risk (35%) compared to laparoscopic approach (4%), making this diagnosis highly likely. 3

Why Imaging (CT or Ultrasound) is Incorrect

Imaging is only indicated for suspected deep collections (abscesses) >3 cm, not for superficial wound infections. 5, 1

• CT or ultrasound would be appropriate if you suspected an intra-abdominal abscess or deep collection, but the clinical picture describes a superficial wound problem (red, swollen, tender at the incision site). 5
• Imaging delays definitive treatment and adds unnecessary cost when the diagnosis is clinically apparent. 2
• For small collections (<3 cm), guidelines advocate antibiotics with possible needle aspiration, not advanced imaging. 5

Why Broad-Spectrum Antibiotics Alone is Incorrect

Antibiotics without drainage have no proven benefit for established SSI. 2

Antibiotics would only be indicated as an adjunct if systemic signs are present:

• Temperature ≥38.5°C
• Heart rate ≥100-110 bpm
• Erythema/induration extending >5 cm from the wound edge
• Purulent drainage after initial drainage
• WBC >12,000 cells/µL 2

If none of these systemic criteria are met, antibiotics add no value even after drainage. 2 The question doesn't mention fever, tachycardia, or extensive cellulitis—only local wound signs.

Practical Management Algorithm

1. Open the wound at the bedside using local anesthesia if needed. 6
2. Express any purulent material and irrigate the wound cavity. 6
3. Leave the wound open to heal by secondary intention with regular dressing changes—do not pack the cavity routinely as this is painful and adds no benefit. 2
4. Assess for systemic criteria (fever >38.5°C, HR >100-110, erythema >5 cm, WBC >12,000). 2
5. Add antibiotics only if systemic criteria are present—a short 24-48 hour course is sufficient if needed. 2

Common Pitfalls to Avoid

• Do not delay drainage by ordering imaging first when the diagnosis is clinically obvious—this worsens outcomes. 2
• Do not prescribe antibiotics without drainage—this violates evidence-based guidelines and promotes resistance. 2, 7
• Do not assume all postoperative wound problems need imaging—reserve CT/US for suspected deep or intra-abdominal collections. 5, 1
• Do not pack the wound cavity routinely—this increases pain and cost without improving healing. 2

Bacteriology Considerations

If cultures are obtained, expect extended-spectrum β-lactamase-producing E. coli or Enterococcus species as the most common organisms after abdominal surgery, with only 23% sensitivity to standard prophylactic antibiotics. 3 However, drainage remains more important than antibiotic choice for superficial SSI. 2