What is the treatment for perforated appendicitis?

Treatment of Perforated Appendicitis

Urgent appendectomy (laparoscopic or open) is the standard of care for perforated appendicitis with diffuse peritoneal contamination, and surgery should not be delayed once the diagnosis is established. 1

Immediate Surgical Management for Diffuse Peritonitis

For patients with perforated appendicitis and diffuse peritoneal signs, proceed directly to urgent appendectomy without delay. 1 Both laparoscopic and open approaches are acceptable, with the choice based on surgeon expertise and available resources. 1 During the COVID-19 pandemic, guidelines recommended open approach for proven COVID-19 patients, though laparoscopy could be considered with adequate protective devices. 2

Antibiotic Therapy

• Initiate broad-spectrum intravenous antibiotics immediately upon diagnosis, covering enteric gram-negative organisms (including E. coli) and anaerobes (including Bacteroides species). 2, 1

• Recommended regimens include: 2

  • Piperacillin-tazobactam
  • Ampicillin-sulbactam
  • Ticarcillin-clavulanate
  • Imipenem-cilastatin
  • Combination therapy: ampicillin + clindamycin (or metronidazole) + gentamicin
  • Alternative: ceftriaxone-metronidazole

• Metronidazole is not needed when using broad-spectrum agents like aminopenicillins with β-lactam inhibitors or carbapenems. 2

Postoperative Antibiotic Duration

• For adults with perforated appendicitis, continue antibiotics postoperatively based on clinical response, typically 5-7 days total. 2

• For pediatric patients with complicated appendicitis, switch to oral antibiotics after 48 hours with total therapy duration shorter than 7 days. 2 This approach is safe, effective, and cost-efficient. 2

• For uncomplicated appendicitis in children, postoperative antibiotics are not recommended. 2

Conservative Management for Localized Disease

Patients presenting with well-circumscribed periappendiceal abscess or phlegmon several days after symptom onset may be managed conservatively with antibiotics ± percutaneous drainage, with appendectomy deferred. 1

Selection Criteria for Conservative Management

• Hemodynamically stable patients 2
• Localized abdominal tenderness without diffuse peritonitis 3
• CT-confirmed abscess or phlegmon 4, 3
• No palpable mass required for conservative approach 3

Conservative Management Protocol

• Initiate intravenous antibiotics immediately 4, 3
• Perform CT-guided percutaneous drainage only if patient fails to improve after 48-72 hours 4 Note that 58% of abscesses do not require drainage. 4
• Serial clinical and imaging monitoring every 3-6 hours with absolute bowel rest and IV hydration 1
• Clinical improvement must occur within 24 hours; if deterioration or progression to sepsis occurs, proceed immediately to surgery 1

Success Rates and Outcomes

• Conservative management succeeds in 92-95% of appropriately selected patients 4, 3
• Mean length of stay for conservative therapy is approximately 7.6 days 4
• Recurrence rate is 6.5% after average follow-up of 30 weeks 3
• Complication rate is approximately 12% 3

Interval Appendectomy

• Recommend interval appendectomy 6-12 weeks after successful conservative management 4
• Interval appendectomy has 10% morbidity and mean length of stay of 1.4 days 4
• However, current evidence shows early appendectomy (when laparoscopic expertise available) is preferable to conservative management, reducing length of stay and readmissions 2

High-Risk Populations Requiring Surgery

The following patient populations should proceed directly to surgical management regardless of presentation: 1

• Immunosuppressed patients 1
• Transplant recipients 1
• Patients with concomitant colonic diseases requiring surgery 1
• Elderly patients (age >65) who have 55-70% perforation rates and threefold increase in mortality per decade 2, 1

Critical Timing Considerations

Delaying surgery beyond 24 hours from admission increases risk of adverse outcomes. 1 However, one study showed that delaying appendectomy up to 15.85 hours after CT diagnosis (to accommodate surgeon preference or hospital efficiency) did not significantly increase wound infections, operative time, or length of stay compared to surgery within 3.18 hours. 5 This suggests brief delays for optimization are acceptable, but surgery should not be delayed to determine COVID-19 status or await test results when appropriate PPE is available. 2

Mortality Risk Stratification

Perforated appendicitis carries approximately 5% mortality compared to <0.1% for non-gangrenous appendicitis, making timely source control critical. 1 The case fatality rate after appendectomy is strongly influenced by age, reaching more than 16% in nonagenarians. 2

Surgical Technique Considerations

• Laparoscopic appendectomy is first choice when appropriate resources and skills are available 2
• For perforated appendicitis with diffuse peritonitis, open approach may be preferable 2
• Hartmann procedure should be preferred over anastomosis for large bowel perforation 2
• Colorectal anastomosis should be avoided in suspected or confirmed COVID-19 patients due to high complication risk 2

Common Pitfalls to Avoid

• Do not delay surgery waiting for swab results when appropriate PPE is available 2
• Do not attempt conservative management in patients with diffuse peritonitis or hemodynamic instability 2, 1
• Do not continue conservative management beyond 24 hours without clinical improvement 1
• Do not underestimate perforation risk in elderly patients 2, 1
• Recognize that gastrointestinal symptoms (diarrhea, abdominal pain, fever) may represent COVID-19 infection 2