What is the management of acute appendicitis?

Management of Acute Appendicitis

Laparoscopic appendectomy is the first-line treatment for acute appendicitis in both adults and children, offering superior outcomes including less postoperative pain, fewer surgical site infections, shorter hospital stays, and faster return to normal activities. 1, 2

Surgical Management: The Gold Standard

Laparoscopic vs. Open Approach

• Laparoscopic appendectomy should be performed whenever laparoscopic equipment and skills are available, as it represents the preferred surgical approach for most patients 1, 2
• Laparoscopic approach results in significantly lower surgical site infection rates (OR 0.43), less postoperative pain on day one, shorter hospital stays, and earlier return to work compared to open appendectomy 1
• The main disadvantage is a slightly higher rate of intra-abdominal abscess formation (OR 1.87) compared to open surgery, though overall complication rates favor laparoscopy 1
• In pediatric patients, the conventional three-port laparoscopic technique is preferred over single-incision approaches due to shorter operative times, less pain, and lower wound infection rates 3

Timing of Surgery

For uncomplicated appendicitis:

• Surgery should be performed within 24 hours of admission 2, 3
• Delaying appendectomy beyond 24 hours is not associated with increased perforation risk or adverse outcomes in uncomplicated cases 1
• There is no need to rush to surgery in the middle of the night for uncomplicated appendicitis 1

For complicated appendicitis (perforation, peritonitis, abscess):

• Early appendectomy within 8 hours is strongly recommended to provide adequate source control and minimize complications 2, 3
• Delaying surgery beyond 8 hours in complicated cases increases complication rates 3

Antibiotic Protocol for Surgical Management

Uncomplicated appendicitis:

• Administer a single preoperative dose of broad-spectrum antibiotics 0-60 minutes before surgical incision 2, 3
• No postoperative antibiotics are needed for uncomplicated cases 3

Complicated appendicitis:

• Initiate IV broad-spectrum antibiotics immediately, covering enteric gram-negative organisms (E. coli) and anaerobes (Bacteroides) 3
• Recommended regimens include: ampicillin + clindamycin (or metronidazole) + gentamicin, ceftriaxone + metronidazole, piperacillin-tazobactam, or ampicillin-sulbactam 3
• For complicated intra-abdominal infections, metronidazole 500 mg every 6 hours + vancomycin (25-30 mg/kg loading dose, then 15-20 mg/kg every 8 hours) may be used 2
• Switch to oral antibiotics after 48 hours if the patient is clinically improving 3
• Total antibiotic duration should be less than 7 days postoperatively 3

Non-Operative Management: A Selective Alternative

Patient Selection Criteria

Non-operative management with antibiotics alone may be considered in highly selected patients with uncomplicated acute appendicitis who meet ALL of the following criteria: 2, 4

• No appendicolith on CT imaging 2, 4
• Appendiceal diameter <13 mm 4
• No mass effect on CT 4
• Patient is medically fit for surgery (in case antibiotics fail) 4
• Patient understands and accepts the 30.7% failure rate requiring appendectomy within one year 3

Predictors of Non-Operative Management Failure

Patients with the following characteristics have higher failure rates and should undergo surgery: 4, 5

• Appendicolith present on imaging (≈40% failure rate) 4
• Appendiceal diameter >10-13 mm 4, 5
• Duration of symptoms >2 days before presentation 5
• Pulse rate >90 bpm 5
• Fever within 24 hours of admission 5
• Total leukocyte count >12,000 cells/dL 5
• C-reactive protein >20 mg/L 5
• Modified Alvarado score ≥9 or Adult Appendicitis Score ≥18 5

Antibiotic Regimen for Non-Operative Management

• Broad-spectrum antibiotics such as piperacillin-tazobactam monotherapy, or combination therapy with cephalosporins or fluoroquinolones plus metronidazole 4
• Initial IV administration followed by oral conversion based on clinical improvement 2
• Total duration typically 8-15 days 6
• Success rate approximately 63-78% at one year follow-up 6

Management of Complicated Appendicitis with Abscess/Phlegmon

Treatment Algorithm

When advanced laparoscopic expertise is available:

• Laparoscopic appendectomy is preferred, as it results in shorter hospital stays and fewer readmissions compared to conservative management 2, 3

When advanced laparoscopic expertise is NOT available:

• Initial non-operative management with IV antibiotics plus percutaneous drainage of abscess is appropriate 1, 2, 3
• Clinical data supports conservative management rather than immediate appendectomy in selected patients with peri-appendiceal abscess or phlegmon 1

Interval appendectomy:

• Routine interval appendectomy is NOT recommended after successful non-operative management, especially in children 3
• Only perform interval appendectomy if recurrent symptoms develop 3
• This avoids unnecessary operative costs and morbidity 3

Special Populations

Pregnant Patients

• Surgical management is preferred over non-operative management, with better maternal and fetal outcomes 1
• Laparoscopic appendectomy is safe in pregnancy with minor advantages (less pain, fewer infections, fewer early deliveries), though fetal loss risk may be slightly increased compared to open surgery 1
• Pregnant patients should undergo timely surgical intervention to decrease complication risk 7

Immunocompromised or Transplant Patients

• Appendectomy should be performed as soon as possible, usually within 24 hours of diagnosis 3
• These patients are at higher risk for complications and should not be managed conservatively 3, 7

Pediatric Patients

• Management principles mirror adult guidelines with emphasis on laparoscopic approach 3
• For uncomplicated appendicitis, do not delay surgery beyond 24 hours from admission 3
• For complicated appendicitis, perform early appendectomy within 8 hours 3
• CT imaging is preferred when diagnosis is uncertain, particularly in children <3 years old 3
• Ultrasound is a reasonable alternative to avoid ionizing radiation 3

Critical Pitfalls to Avoid

• Do not continue postoperative antibiotics beyond 3-5 days for complicated appendicitis with adequate source control 3
• Do not use extended-spectrum antibiotics (piperacillin-tazobactam, carbapenems) routinely in children, as they offer no advantage over narrower-spectrum agents 3
• Do not delay source control beyond 8 hours in complicated cases 3
• Do not perform routine interval appendectomy after successful non-operative management—this adds unnecessary morbidity 3
• Do not attempt non-operative management in patients with appendicolith, mass effect, or dilated appendix >13 mm who are fit for surgery 4

Technical Surgical Considerations

• Simple ligation of the appendicular stump is preferred over inversion of the stump in both open and laparoscopic appendectomy 2
• Routine histopathology should be performed after appendectomy to identify unexpected findings 2
• Open appendectomy via Lanz incision may be considered for hemodynamically unstable patients requiring immediate source control, or when laparoscopic expertise is unavailable 3