What is the mortality rate for perforated (ruptured) appendicitis and what is the recommended management?

Mortality Rate and Management of Ruptured Appendicitis

Perforated appendicitis carries approximately 5% mortality compared to less than 0.1% for non-perforated appendicitis, with elderly patients experiencing mortality rates of 11.9-15%, making urgent surgical source control the standard of care. 1, 2, 3

Mortality Stratification

The mortality risk increases dramatically with disease severity and patient age:

• Non-gangrenous appendicitis: <0.1% mortality 1, 4
• Gangrenous appendicitis: 0.6% mortality 4
• Perforated appendicitis: approximately 5% overall mortality 1, 4
• Elderly patients (>65 years) with perforation: 11.9-15% mortality 5, 2, 3
• Nonagenarians: >16% mortality, with threefold increase per decade after age 65 1, 4

The perforation rate itself is substantially higher in elderly patients at 55-70% compared to younger populations, and delayed presentation (median 4 days from symptom onset) significantly contributes to worse outcomes. 5, 4

Immediate Management Algorithm

For Diffuse Peritonitis or Significant Contamination

Urgent appendectomy (laparoscopic or open) is mandatory and should not be delayed once diagnosis is established. 1

• Both surgical approaches are acceptable, with choice based on surgeon expertise and resource availability 1
• Broad-spectrum IV antibiotics covering gram-negative organisms and anaerobes must be initiated immediately (piperacillin-tazobactam, ampicillin-sulbactam, ticarcillin-clavulanate, imipenem-cilastatin, or combination therapy) 1
• Every hour of surgical delay increases mortality risk by 2.4% 5
• Surgery within 24 hours of symptom onset shows zero mortality compared to operations beyond 48 hours 5

For Localized Disease (Periappendiceal Abscess)

Patients with well-circumscribed abscesses can be managed with percutaneous drainage when feasible, with appendectomy generally deferred. 1

• Small abscesses (<4 cm) or phlegmon not amenable to drainage may be treated with antimicrobial therapy alone in highly selected cases 5, 1
• This approach requires serial clinical and imaging monitoring every 3-6 hours, absolute bowel rest with IV hydration, and close multidisciplinary follow-up 1
• Clinical improvement must occur within 24 hours; any deterioration or progression to sepsis mandates immediate surgery 1

High-Risk Populations Requiring Surgery

The following patients should proceed directly to surgical management regardless of presentation:

• Elderly patients (>65 years): perforation rates 55-70%, mortality 11.9-15% 5, 2, 3
• Immunosuppressed patients and transplant recipients 1
• Patients with concomitant colonic diseases requiring surgery 1
• Patients with diffuse peritonitis, significant pneumoperitoneum, or extraluminal contrast extravasation 5, 1

Postoperative Antibiotic Management

Continue IV antibiotics for 5-7 days total for adults with perforated appendicitis, based on clinical response. 1

• Metronidazole is unnecessary when using broad-spectrum agents like aminopenicillins with β-lactam inhibitors or carbapenems 1
• Pediatric patients can transition to oral antibiotics after 48 hours with total duration <7 days 1

Critical Prognostic Factors

Mortality and morbidity correlate strongly with:

• Peritoneal contamination >150 mL: 100% increase in morbidity and mortality (54.5%) 6
• Perforation at appendiceal base: higher complication rates 6
• Delayed presentation: mean 3.8 days for perforated vs 2.3 days for non-perforated cases 3
• Comorbid conditions: 75% complication rate in perforated cases vs 16.2% in non-perforated 3

Common Complications

The overall complication rate in perforated appendicitis is 72-75%: 3, 6

• Surgical site infection: 18.6-42% (most common) 7, 6
• Wound dehiscence: 15.2-16.6% 7, 6
• Pelvic abscess: 13.5% 7
• Intestinal obstruction: 1.6-2.4% 6
• Mortality: 4.8-6.3% overall, 15% in perforated cases 3, 6

Mean hospital stay for perforated appendicitis is 7.2 days compared to 5.1 days for non-perforated cases. 3

Key Clinical Pitfalls

Avoid delaying surgery in elderly patients with atypical presentations—the clinical diagnosis of appendicitis is correct in only 69.8% of elderly patients on initial presentation, yet their perforation rates and mortality are dramatically higher. 3

Do not rely on duration of symptoms alone to predict perforation risk—while some data suggest delayed presentation increases perforation rates, appendicitis may represent two distinct disease processes (uncomplicated vs complicated) rather than a progressive continuum. 5

Routine intraperitoneal drainage does not reduce pelvic abscess incidence and should not be used reflexively. 7