What is the recommended treatment for a long-standing infection involving a laparotomy or closed colostomy wound?

Management of Long-Standing Infection in Laparotomy or Closed Colostomy Wounds

For long-standing infections involving laparotomy or closed colostomy wounds, open the wound immediately with incision and drainage, obtain wound cultures, initiate broad-spectrum antibiotics covering gram-negative bacteria and anaerobes, and manage the wound open with regular dressing changes rather than attempting re-closure. 1

Immediate Surgical Management

The primary intervention is prompt incision and drainage of the infected wound. 1 This requires:

• Remove sutures as necessary to facilitate adequate drainage of all infected material 1
• Obtain wound cultures before initiating antibiotics to guide subsequent therapy 1
• Perform aggressive debridement if necrotic tissue is present, continuing into healthy-looking tissue 2
• Leave the wound open rather than attempting primary re-closure, as open wound management is strongly preferred for established surgical site infections 1

The evidence is clear that delayed drainage leads to progression of infection and worse outcomes 1. This is particularly critical in colostomy-related wounds where fecal contamination creates a polymicrobial environment.

Antibiotic Therapy

Initiate empiric broad-spectrum antibiotics immediately after obtaining cultures, covering both aerobic gram-negative bacteria and anaerobes. 1

Recommended Regimens:

• Standard regimen: Combination therapy covering Enterobacterales (E. coli) and Clostridiales 2
• For penicillin allergy: Fluoroquinolone (ciprofloxacin) plus metronidazole 1
• Choose antibiotics with the narrowest effective spectrum to avoid selecting resistant bacteria 2
• Adjust dosing based on weight and organ function to optimize tissue concentrations 2

Duration: 7-10 days for uncomplicated surgical site infections; longer courses may be required for deeper tissue involvement 1. Discontinue antibiotics when clinical signs of infection have resolved 1.

The evidence does not support prolonged antibiotic courses beyond what is clinically necessary 2. Tailor therapy rapidly based on culture results and clinical response 2.

Wound Care Strategy

Manage the wound open with regular cleansing and dressing changes. 1

Advanced Wound Management:

• Consider negative-pressure wound therapy (NPWT) for complex or deep infections after complete debridement of necrotic tissue 2, 1
• NPWT accelerates healing by improving local blood supply, reducing edema, absorbing exudates, and inhibiting bacterial growth 2
• For colostomy-related wounds with ongoing fecal contamination, consider fecal diversion devices as an alternative to re-creating a colostomy 2
• These silicone tubes protect wounds from fecal contamination and can be combined with NPWT 2

The 2018 WSES guidelines specifically recommend NPWT after complete necrosis removal in necrotizing infections (1C recommendation) 2. For prophylactic use on closed high-risk incisions, the 2023 WSES guidelines provide a strong recommendation (1A) 2, though this applies to prevention rather than treatment of established infection.

Special Considerations for Colostomy Closure Wounds

Colostomy closure wounds have inherently higher infection risk due to bacterial contamination. 3, 4

• Historical data shows wound infection rates of 4.8-14% even with optimal prophylaxis 3, 4
• Primary closure is acceptable for initial colostomy closure with proper mechanical and antibiotic preparation 3
• However, once infection is established, re-closure is contraindicated 1
• Delayed primary closure does not reduce infection rates compared to immediate primary closure when proper preparation is used 3

For severe intra-abdominal infections complicating colorectal disease, laparostomy (leaving the abdomen open) is an effective management strategy with acceptable mortality (28.6% in one series) 5. Most wounds are left to heal by granulation and contraction, with some requiring later reconstructive surgery 5.

Monitoring and Follow-Up

Regular assessment is essential to ensure treatment response and identify complications early. 1

• Monitor for systemic signs: fever, tachycardia, leukocytosis indicating sepsis 1
• Assess wound healing progress at each dressing change 1
• Consider imaging (ultrasound or CT) if concerned about deeper abscess formation or undrained collections 1
• Optimize nutritional status to support wound healing 1
• Ensure glycemic control in diabetic patients 1

Critical Pitfalls to Avoid

• Never attempt primary re-closure of an established infected wound - this leads to treatment failure 1
• Do not delay drainage - progression of infection significantly worsens outcomes 1
• Avoid inadequate antibiotic spectrum - must cover both aerobic and anaerobic organisms in colorectal-related infections 1
• Do not prematurely discontinue antibiotics - complete the full course even if wound appears improved 1
• Do not ignore underlying factors - nutritional deficiencies and poor glycemic control impair healing 1

Algorithm for Decision-Making

1. Confirm infection diagnosis (erythema, purulence, systemic signs)
2. Immediate incision and drainage with suture removal as needed 1
3. Obtain wound cultures before antibiotics 1
4. Start empiric broad-spectrum antibiotics (gram-negative + anaerobic coverage) 1
5. Leave wound open with regular dressing changes 1
6. Consider NPWT for complex wounds after debridement 2, 1
7. Tailor antibiotics based on culture results 2
8. Continue treatment for 7-10 days or until clinical resolution 1
9. Monitor closely for complications requiring escalation 1