What is the management for a patient with abdominal pain and no bowel movement for 7 days?

Management of Abdominal Pain with 7 Days of Constipation

This patient requires immediate CT abdomen/pelvis with IV contrast to rule out bowel obstruction, perforation, or other surgical emergencies, followed by urgent surgical consultation if imaging reveals mechanical obstruction or signs of peritonitis. 1, 2

Immediate Assessment and Stabilization

Check vital signs immediately for fever >37.8°C, heart rate >90 bpm, tachypnea, hypotension, or altered mental status—these indicate potential sepsis, bowel ischemia, or perforation requiring immediate resuscitation. 1, 2, 3

• Establish IV access and initiate fluid resuscitation if hemodynamic instability is present 1, 2
• Administer low-molecular-weight heparin for VTE prophylaxis, as acute abdominal conditions carry high thrombotic risk 1, 2, 3
• Do NOT give laxatives or prokinetics until mechanical obstruction is excluded—these can precipitate perforation in obstructed bowel 4

Critical Physical Examination Findings

Look for specific high-risk features:

• Peritoneal signs (guarding, rebound tenderness, rigid abdomen) suggest perforation or ischemia and mandate immediate surgical consultation 4, 1
• Absent bowel sounds indicate ileus or complete obstruction 4
• Abdominal distension with tympany suggests bowel obstruction 4
• Rectal examination may reveal impaction or rectal mass 4
• Visible peristalsis or severe pain after eating suggests mechanical obstruction 4

Laboratory Testing

Order immediately:

• Complete blood count to assess for leukocytosis (infection/ischemia) or anemia (chronic bleeding) 2, 3
• Serum lactate—elevated levels strongly suggest bowel ischemia or sepsis 1, 2, 3
• C-reactive protein—more sensitive than WBC alone for surgical abdominal disease 2, 3
• Electrolytes, BUN, creatinine to assess dehydration and metabolic derangements 3

Imaging Strategy

Obtain CT abdomen/pelvis with IV contrast as the primary diagnostic test—this changes diagnosis in 51-54% of cases and alters management in 25-42% of patients. 1, 2

• Do NOT delay CT for oral contrast—it delays diagnosis without improving accuracy 1
• Single-phase IV contrast is sufficient; pre-contrast phases are unnecessary 1
• Plain abdominal X-rays have limited utility and should be avoided unless CT is unavailable 1
• CT will identify: mechanical obstruction with transition point, perforation (free air), bowel ischemia, fecal impaction, masses, or toxic megacolon 4, 1

Differential Diagnosis Priority

Seven days without bowel movement plus abdominal pain raises concern for:

1. Mechanical bowel obstruction (adhesions, malignancy, stricture)—look for transition point on CT 4, 5
2. Fecal impaction—especially in elderly or opioid users 4
3. Colonic pseudo-obstruction (Ogilvie syndrome)—massive colonic dilation without mechanical cause 4
4. Perforated viscus—if peritoneal signs present 4, 1
5. Opioid-induced bowel dysfunction or narcotic bowel syndrome—ask about chronic opioid use 4

Antibiotic Decision

Do NOT routinely administer antibiotics for undifferentiated abdominal pain. 1, 2, 3

Antibiotics are indicated ONLY when:

• Intra-abdominal abscess identified on imaging 1, 2
• Clinical signs of sepsis (fever, hypotension, altered mental status) 1, 2
• Perforation confirmed 4, 1
• Stool cultures confirm C. difficile or other bacterial infection 4

Pain Management

• Provide early analgesia without compromising diagnostic accuracy 1, 6
• Avoid opioids—they worsen constipation, cause narcotic bowel syndrome, and increase mortality in chronic abdominal pain 4, 1

When to Involve Surgery Immediately

Surgical consultation is mandatory for: 1, 2, 3

• Signs of peritonitis (guarding, rebound, rigidity)
• Free air on imaging (perforation)
• Complete mechanical bowel obstruction on CT
• Hemodynamic instability despite resuscitation
• Toxic megacolon (transverse colon >5.5 cm) 4
• Bowel ischemia or mesenteric ischemia
• Failed conservative management after 48-72 hours

Conservative Management (Only if Obstruction Excluded)

If CT shows no mechanical obstruction and patient is stable:

• Bowel rest (NPO initially) 5
• IV fluid resuscitation to correct dehydration 5
• Nasogastric decompression if significant distension or vomiting 5
• Correct electrolyte abnormalities 5
• Consider water-soluble contrast study (Gastrografin) which is both diagnostic and therapeutic in partial obstruction 4

Common Pitfalls to Avoid

• Never give laxatives or enemas before excluding mechanical obstruction—risk of perforation 4
• Do not assume "just constipation" in a patient with 7 days of obstipation plus pain—this warrants full workup 4
• Elderly patients may have normal labs despite serious pathology—rely on imaging 1
• Opioid users may have narcotic bowel syndrome masquerading as obstruction—requires opioid withdrawal, not escalation 4