What is the recommended treatment for a patient with abdominal pain, distention, and a taut abdomen, following a CT scan of the abdomen and pelvis?

Management of Abdominal Pain and Distention After CT Abdomen and Pelvis

CT abdomen and pelvis with IV contrast is the recommended imaging study for evaluating this patient with worsening abdominal distention, taut abdomen, and discomfort following initial CT imaging. 1

Initial Assessment

• Perform a focused physical examination to evaluate the taut and distended abdomen, looking specifically for peritoneal signs (rebound tenderness, guarding), which would indicate possible peritonitis 2
• Check vital signs for fever, tachycardia, or hypotension which may indicate infection or sepsis 3
• Review the results of the initial CT abdomen and pelvis to identify any findings that may explain the worsening symptoms 2
• Obtain laboratory studies including complete blood count to assess for leukocytosis, comprehensive metabolic panel, and urinalysis 3

Diagnostic Approach

Imaging Considerations

• If the initial CT findings were inconclusive or if the patient's condition has significantly worsened, a repeat CT abdomen and pelvis with IV contrast is indicated 1
• IV contrast improves characterization and detection of subtle bowel wall abnormalities and complications such as abscess formation 2
• CT has been shown to change the leading diagnosis in 49% of patients and alter management plans in 42% of patients with nontraumatic abdominal pain 1

Potential Diagnoses to Consider

1. Intra-abdominal infection/abscess

   • If CT shows a fluid collection >3 cm, percutaneous drainage (PCD) is recommended 2
   • Empiric broad-spectrum antibiotics should be initiated while awaiting culture results 2

2. Diverticulitis

   • CT is the most accurate diagnostic tool (98% accuracy) for diverticulitis 2
   • Treatment depends on severity: medical therapy for uncomplicated cases, catheter drainage for abscesses ≥3 cm, and surgery for free perforation and peritonitis 2

3. Bowel obstruction

   • CT can identify constipation-related complications such as fecal impaction or bowel obstruction 1
   • Management may include nasogastric decompression and possible surgical intervention 2

4. Iatrogenic perforation (if patient recently had colonoscopy)

   • CT is the most accurate imaging tool to diagnose perforation 2
   • Management ranges from conservative treatment to surgical intervention depending on clinical status 2

Treatment Recommendations

Antimicrobial Therapy

• For suspected intra-abdominal infection, initiate empiric broad-spectrum antibiotics 2
• Options include:
  • Cefepime (2g IV every 12 hours) plus metronidazole (500mg IV every 6 hours), which has shown 81% clinical cure rate in complicated intra-abdominal infections 4
  • Piperacillin-tazobactam, which has broad-spectrum activity against most Gram-positive, Gram-negative aerobic and anaerobic bacteria 5, 6

Interventional Management

• For localized fluid collections or abscesses >3 cm identified on CT, percutaneous drainage is indicated 2
• The approach (transabdominal, transgluteal, etc.) depends on the specific location of the collection 2

Surgical Considerations

• Surgical consultation should be obtained if there are signs of peritonitis, free perforation, or bowel ischemia 2
• Early surgical intervention (within 24 hours of perforation) is associated with better outcomes if perforation is suspected 2

Monitoring and Follow-up

• Close monitoring of vital signs, abdominal examination, and laboratory values is essential 2
• If the patient does not respond to initial therapy within 4-7 days, further diagnostic investigation including repeat CT imaging should be performed 2
• Extra-abdominal sources of infection and non-infectious inflammatory conditions should also be investigated if the patient is not experiencing a satisfactory clinical response 2

Pitfalls to Avoid

• Do not rely solely on abdominal X-rays for diagnosis, as they have limited diagnostic value and may miss significant pathology 1
• Do not assume constipation is always functional without appropriate imaging when pain is a significant feature 1
• Early improvement with conservative treatment does not rule out the potential need for surgery; continue close monitoring 2
• Do not delay surgical intervention if there are signs of peritonitis or clinical deterioration 2