Secondary peritonitis

• abscess
• bowel perforation
• ruptured appendix

- Drainage and debridement essential.

- Blood and peritoneal cultures recommended for any high-risk community-acquired (ICU/critically ill, diffuse peritonitis, delayed or inadequate source control) peritonitis, and all cases of healthcare-associated peritonitis. If source control achieved, cultures of perforated or gangrenous appendix offer no benefit.

- Duration of therapy:

Peri-operative therapy ≤ 24h:

• bowel injuries due to penetrating, blunt, or iatrogenic trauma with surgery within 12 hours of injury;
• acute perforations of stomach, duodenum, and proximal jejunum in absence of antacid therapy or malignancy with surgery within 24 hours;
• acute appendicitis without perforation, abscess, or peritonitis;
• ischemic, non-perforated bowel.

Adequate source control - 2 days post-op with laparoscopic; 4 days with open surgical approach; 7 days if bacteremic

Source control delayed or not performed – 5-7 days:

• Monitor the following to determine if antimicrobial therapy can be discontinued sooner:
  • temperature
  • WBC/differential
  • return of GI function
• Persistent clinical evidence of infection after 5-7 days warrants diagnostic investigations (CT, US).

Usual Pathogens

Polymicrobial:

Enterobacterales

Enterococcus spp

Anaerobes

Streptococcus spp

Yeast

Community-acquired, low risk

Alternative

Penicillin and ceftriaxone allergy

Community-acquired, high risk:

•  ICU/critically ill

•  diffuse peritonitis

•  delayed or inadequate source control

or

Healthcare-associated

Penicillin allergy/multiple previous antibiotics/known ceftriaxone-resistant Gram negative organism

Oral switch therapy

- Switch to oral agents when tolerating oral intake and clinical improvement.

Penicillin allergy