What is the initial approach to treating small bowel enteritis?

Initial Approach to Small Bowel Enteritis

The initial approach to small bowel enteritis depends critically on hemodynamic stability and the presence of complications: stable patients without perforation or sepsis should receive supportive care with IV fluids, electrolyte correction, and selective antibiotic therapy only when bacterial superinfection or abscess is suspected, while unstable patients or those with perforation require immediate surgical exploration. 1

Immediate Assessment and Stabilization

Hemodynamic Status Determination

• All patients presenting with small bowel enteritis require adequate volume resuscitation with intravenous fluids, correction of electrolyte abnormalities and anemia, and low molecular weight heparin for thromboprophylaxis. 1
• Hemodynamically unstable patients warrant immediate surgical exploration according to damage control principles. 1

Diagnostic Imaging

• Ultrasound and CT with IV contrast are the primary imaging modalities to assess for intestinal wall thickening, signs of inflammation, perforation (extraluminal gas, intra-abdominal fluid), or abscess formation. 1
• CT angiography should be performed if acute mesenteric ischemia is suspected or in stable patients with ongoing bleeding after resuscitation. 1

Medical Management for Stable Patients

Antibiotic Therapy Indications

• Antibiotics should NOT be routinely administered in small bowel enteritis—reserve them only for documented superinfection or intra-abdominal abscess. 1
• When antibiotics are indicated, empiric therapy must cover Gram-negative aerobic/facultative bacilli, Gram-positive streptococci, and obligate anaerobic bacilli. 1

Antibiotic Selection Based on Clinical Scenario

For adequate source control in immunocompetent, non-critically ill patients:

• Piperacillin/tazobactam 6 g/0.75 g loading dose, then 4 g/0.5 g every 6 hours or 16 g/2 g by continuous infusion. 1
• Duration: 4 days if source control is adequate. 1

For beta-lactam allergy:

• Eravacycline 1 mg/kg every 12 hours OR Tigecycline 100 mg loading dose then 50 mg every 12 hours. 1

For critically ill or immunocompromised patients with adequate source control:

• Piperacillin/tazobactam (same dosing as above) OR Eravacycline 1 mg/kg every 12 hours. 1
• Duration: up to 7 days based on clinical conditions and inflammatory markers. 1

For inadequate/delayed source control or high risk of ESBL-producing organisms:

• Ertapenem 1 g every 24 hours OR Eravacycline 1 mg/kg every 12 hours. 1

For septic shock:

• Meropenem 1 g every 6 hours by extended/continuous infusion, OR
• Doripenem 500 mg every 8 hours by extended/continuous infusion, OR
• Imipenem/cilastatin 500 mg every 6 hours by extended infusion, OR
• Eravacycline 1 mg/kg every 12 hours. 1

Nutritional Support

• Total parenteral nutrition should be reserved for nutritionally deficient patients unable to tolerate enteral nutrition, particularly when the enteral route is contraindicated in critically ill patients with shock, intestinal ischemia, high-output fistula, or severe hemorrhage. 1
• Preoperative nutritional support is mandatory in severely undernourished patients. 1

Surgical Indications

Immediate Surgery Required

• Free perforation with generalized peritonitis 1
• Hemodynamic instability despite resuscitation 1
• Signs of septic shock 1
• Radiological signs of pneumoperitoneum with free fluid in acutely unwell patients 1

Surgical Approach Options

For perforation with ischemia:

• Open or laparoscopic small bowel segmental resection with primary anastomosis in stable patients. 1
• In perforation due to small bowel ischemia: resection with delayed anastomosis at second-look operation, potentially with open or endovascular mesenteric vessel reconstruction. 1

For critically ill patients or severe inflammation:

• Resection with stoma creation or exteriorization of perforation as stoma when tissue is friable and precludes safe anastomosis. 1

Monitoring and Re-evaluation

• Clinical improvement should occur within 3-5 days of starting appropriate therapy. 1
• Patients with ongoing signs of infection or systemic illness beyond 7 days of antibiotic treatment warrant diagnostic investigation to assess for inadequate source control, undrained abscess, or alternative diagnosis. 1
• Repeat imaging is indicated if the patient's condition does not improve to determine adequacy of drainage or need for surgical intervention. 1

Critical Pitfalls to Avoid

• Do not delay surgery in unstable patients or those with perforation while attempting medical management. 1
• Avoid routine antibiotic use without clear indication of bacterial infection or abscess—this represents inappropriate antimicrobial stewardship. 1
• Do not perform sigmoidoscopy or colonoscopy in patients with suspected obstruction or toxic megacolon due to increased perforation risk. 1