A 28-year-old woman with a 3-day history of right lower quadrant pain, fever, and vomiting presents to the hospital. On examination, she is febrile (38.8°C), has localized RLQ tenderness with guarding, and a palpable mass in the right iliac fossa. Her WBC is 16,500/μL. Ultrasound shows a dilated, thick-walled appendix with surrounding free fluid and a hypoechoic mass suggesting abscess formation. What is the most appropriate next step in management?

Explanation

## Perforated Appendicitis with Abscess: Management Strategy **Key Point:** In perforated appendicitis with a localized, contained abscess, percutaneous drainage followed by interval appendicectomy is the preferred approach. This reduces morbidity and mortality compared to emergency surgery in a septic, unstable patient. ### Clinical Assessment: Complicated Appendicitis This patient demonstrates: - **Perforation indicators:** 3-day duration, fever, vomiting, peritoneal guarding - **Abscess formation:** palpable mass, surrounding free fluid on ultrasound, hypoechoic collection - **Systemic inflammation:** elevated WBC, fever - **Contained infection:** localized mass suggests walled-off perforation (NOT diffuse peritonitis) **High-Yield:** The presence of a **palpable mass** and **localized abscess** on imaging indicates a contained perforation. This is the classic indication for percutaneous drainage + interval appendicectomy, NOT emergency surgery. ### Management Algorithm for Perforated Appendicitis ```mermaid flowchart TD A[Perforated appendicitis]:::outcome --> B{Abscess present?}:::decision B -->|No abscess, diffuse peritonitis| C[Resuscitation + emergency appendicectomy]:::urgent B -->|Localized, contained abscess| D[Percutaneous drainage]:::action D --> E[Broad-spectrum antibiotics]:::action E --> F[Interval appendicectomy after 6-8 weeks]:::action B -->|Uncomplicated perforation| G[Emergency appendicectomy]:::action C --> H[High morbidity/mortality]:::outcome F --> I[Lower morbidity, planned surgery]:::outcome ``` ### Why Percutaneous Drainage + Interval Surgery? | Aspect | Emergency Surgery | Percutaneous Drainage + Interval Surgery | |--------|-------------------|------------------------------------------| | **Timing** | Immediate, in septic patient | After stabilization (6–8 weeks) | | **Morbidity** | High (sepsis, anastomotic leak, adhesions) | Lower (planned elective surgery) | | **Mortality** | Higher in unstable patients | Lower with preoperative optimization | | **Indication** | Diffuse peritonitis, no abscess | Localized, contained abscess | | **Patient stability** | Often hemodynamically unstable | Time to optimize before elective surgery | **Clinical Pearl:** The **palpable mass** in the RLQ is a key finding indicating that the patient's immune system has successfully walled off the infection. This is a favorable sign for conservative management with drainage and antibiotics. **Mnemonic: DRAIN — Delay surgery, Resuscitate, Abscess drainage percutaneously, Interval appendicectomy, Normalize patient status** ### Rationale for Interval Appendicectomy 1. **Allows inflammation to resolve:** 6–8 weeks permits the inflammatory mass to regress 2. **Reduces operative difficulty:** Dissection is easier in a non-inflamed field 3. **Prevents recurrent appendicitis:** Definitive removal of the appendix after recovery 4. **Better outcomes:** Lower rates of anastomotic leak, infection, and adhesion formation [cite:Sabiston Textbook of Surgery Ch 50; Harrison 21e Ch 297]