What is the preoperative preparation for a patient with acute appendicitis?

Preoperative Preparation for Acute Appendicitis

A single preoperative dose of broad-spectrum antibiotics given 0-60 minutes before surgical skin incision is essential for all patients with acute appendicitis undergoing appendectomy. 1

Diagnosis Confirmation

• Diagnosis should be confirmed using clinical scoring systems (Alvarado, AIR, or AAS scores) combined with appropriate imaging 1
• Point-of-care ultrasound (POCUS) is recommended as the first-line diagnostic imaging tool in both adults and children when imaging is indicated based on clinical assessment 1, 2
• If ultrasound is inconclusive, low-dose contrast-enhanced CT scan is preferred for adolescents and young adults 1, 2
• For pregnant patients, graded compression trans-abdominal ultrasound is the preferred initial imaging method, with MRI as second-line to avoid ionizing radiation 1, 2

Preoperative Antibiotic Administration

• Administer a single preoperative dose of broad-spectrum antibiotics 0-60 minutes before surgical skin incision 1, 2
• Appropriate antibiotic options include:
  • For uncomplicated appendicitis: Second or third-generation cephalosporins like cefoxitin (1-2g IV) 3
  • For complicated appendicitis: Broader-spectrum coverage with piperacillin-tazobactam, ampicillin-sulbactam, or combination therapy with cephalosporins plus metronidazole 1, 4
• Postoperative antibiotics are not recommended for uncomplicated appendicitis 1, 5
• For complicated appendicitis (perforation, peritonitis), continue antibiotics postoperatively 1, 5

Fluid Resuscitation and Optimization

• Ensure adequate intravenous hydration to correct fluid deficits from decreased oral intake, fever, and inflammatory response 2
• Correct electrolyte abnormalities if present 2
• Administer appropriate pain medication and antipyretics as indicated 1, 2

Timing of Surgery

• Surgery should be performed as soon as reasonably feasible after diagnosis 1, 2
• Delaying appendectomy beyond 24 hours from admission is associated with increased risk of adverse outcomes 2
• For patients with complicated appendicitis (perforation, peritonitis), urgent surgical intervention is required for adequate source control 1, 2
• Evidence suggests that delaying operation for a short period (up to 10 hours after diagnosis) to accommodate surgeon availability does not significantly increase complications 6

Surgical Approach

• Laparoscopic appendectomy is preferred over open appendectomy when laparoscopic equipment and expertise are available 2
• Both laparoscopic and open appendectomy are acceptable procedures, with the approach dictated by the surgeon's expertise 1

Special Patient Populations

• For pregnant patients: Use ultrasound as first-line imaging, followed by MRI if inconclusive 1, 2
• For pediatric patients: Imaging should be performed, particularly for those <3 years old, with ultrasound preferred over CT to avoid radiation 1, 2
• For patients with complicated appendicitis and a well-circumscribed periappendiceal abscess: Consider percutaneous drainage rather than immediate appendectomy 1

Non-Operative Management Considerations

• In selected patients with uncomplicated appendicitis without appendicolith, non-operative management with antibiotics may be discussed as an alternative to surgery 1, 2
• Patients should be informed of a potential recurrence rate of up to 39% within 5 years with non-operative management 1
• CT findings of appendicolith, mass effect, or a dilated appendix >13mm are associated with higher risk of antibiotic treatment failure (~40%) 4

Common Pitfalls to Avoid

• Delaying antibiotic administration until after surgery 1, 2
• Prolonging preoperative preparation beyond 24 hours, which increases risk of perforation 2
• Failing to recognize complicated appendicitis requiring urgent intervention 1, 2
• Inadequate fluid resuscitation before surgery 2
• Using inappropriate antibiotic regimens that don't cover enteric gram-negative organisms and anaerobes 1, 4