What is the definitive management and full treatment plan for acute appendicitis, including peri‑operative antibiotics, surgical approach, and postoperative care?

Definitive Management of Acute Appendicitis

Laparoscopic appendectomy within 24 hours of admission is the gold standard treatment for acute appendicitis, with a single preoperative dose of broad-spectrum antibiotics given 0-60 minutes before incision and no postoperative antibiotics for uncomplicated cases. 1, 2

Initial Assessment and Surgical Timing

• Perform appendectomy within 24 hours of hospital admission to minimize complications and adverse outcomes 2
• Delaying surgery beyond 24 hours significantly increases morbidity and should be avoided 2
• Use intra-operative grading systems (WSES 2015 or AAST EGS grading) to classify disease severity and guide postoperative management 3

Surgical Approach

Laparoscopic appendectomy is the preferred method due to less postoperative pain, lower surgical site infection rates, shorter hospital stays, earlier return to work, and better quality of life compared to open surgery 2

• The laparoscopic approach should be used where equipment and expertise are available 2
• Maintain a low threshold for conversion to open if technical difficulties arise 3
• Remove the appendix even if it appears "normal" during surgery when no other disease is found in symptomatic patients 3

Perioperative Antibiotic Management

Uncomplicated Appendicitis

Administer a single IV dose of broad-spectrum antibiotics 0-60 minutes before skin incision 1, 2

• Acceptable regimens include cefazolin, piperacillin-tazobactam, ampicillin-sulbactam, or ticarcillin-clavulanate 4
• No postoperative antibiotics are required for uncomplicated appendicitis with adequate source control 1, 4
• This single-dose approach applies to both adults and children 1

Complicated Appendicitis (Perforated, Gangrenous, or Abscess)

Continue postoperative broad-spectrum antibiotics but limit duration to 3-5 days maximum when adequate source control is achieved 1, 4

• Antibiotics can be discontinued after 24 hours if complete source control was achieved during surgery 4
• Prolonged courses beyond 3-5 days provide no additional benefit in reducing infectious complications 4
• Use broad-spectrum coverage: piperacillin-tazobactam, ampicillin-sulbactam, ticarcillin-clavulanate, or carbapenems 4
• Extended-spectrum antibiotics offer no advantage over narrower-spectrum agents when adequate source control is achieved 4

For pediatric patients with complicated appendicitis: Switch to oral antibiotics after 48 hours if clinically improving, with total duration less than 7 days 4, 2

Management of Appendiceal Abscess or Phlegmon

Two acceptable approaches exist, depending on available expertise:

Non-Operative Management (When Advanced Laparoscopic Expertise Unavailable)

• Initiate IV antibiotics with optional percutaneous drainage if abscess is accessible 3
• This approach is associated with 12-24% recurrence rates 3

Laparoscopic Surgery (Preferred When Expertise Available)

Laparoscopic approach is the treatment of choice for appendiceal abscess when advanced laparoscopic expertise is available 3

• This approach results in shorter hospital stays, fewer readmissions, and fewer additional interventions compared to conservative treatment 3
• Maintain a low threshold for conversion to open 3

Interval Appendectomy Decisions

Do NOT perform routine interval appendectomy after non-operative management in patients <40 years old 3

• Only perform interval appendectomy for patients with recurrent symptoms 3
• The number needed to treat is 8 patients to prevent one recurrence, making routine interval appendectomy cost-ineffective 3

For patients ≥40 years old treated non-operatively: Perform both colonoscopy and interval full-dose contrast-enhanced CT scan due to 3-17% incidence of appendicular neoplasms 3, 4

Postoperative Care

• Send all appendectomy specimens for routine histopathology to identify unexpected findings 3
• Do not place drains following appendectomy for complicated appendicitis, as they provide no benefit and may prolong hospitalization 2

Non-Operative Management Alternative (Selected Cases Only)

For highly selected patients with uncomplicated appendicitis who decline surgery or are poor surgical candidates:

• Initiate IV amoxicillin-clavulanate 1.2-2.2 g every 6 hours OR ceftriaxone 2 g daily plus metronidazole 500 mg every 6 hours 1
• Transition to oral antibiotics after 48-72 hours based on clinical improvement 1
• Total antibiotic duration: 7-10 days 1

Patient selection criteria for antibiotic-only approach:

• Imaging confirmation of NO appendicolith 1, 5
• Appendiceal diameter <13 mm without mass effect 1, 5
• Clinical stability without sepsis, peritonitis, or perforation 1
• Age <40 years preferred 1

Critical counseling points:

• Initial success rate: 70-88.5% 1
• One-year success rate: only 73% compared to 97% with surgery 1
• Recurrence risk: 23-39% over 5 years, with 11-14% recurring within the first year 1
• CT findings of appendicolith, mass effect, or appendiceal diameter >13 mm predict approximately 40% treatment failure 5

Common Pitfalls to Avoid

• Do not administer postoperative antibiotics for uncomplicated appendicitis—this provides no benefit and increases antibiotic resistance 1, 4
• Do not continue antibiotics beyond 3-5 days for complicated appendicitis with adequate source control—prolonged courses are unnecessary 1, 4
• Do not confuse gangrenous with perforated appendicitis—only perforated cases with inadequate source control require extended antibiotics 4
• Do not delay surgery beyond 24 hours—this significantly increases complications 2
• Do not perform routine interval appendectomy in young patients—only do so for recurrent symptoms 3