How is abdominal distension managed?

Management of Abdominal Distension

The management of abdominal distension should target the underlying cause while focusing on symptom relief through dietary modifications, medications, and behavioral therapies to improve patient morbidity, mortality, and quality of life.

Diagnostic Approach

• Abdominal distension is defined as a measurable increase in abdominal girth, often accompanied by subjective bloating (sensation of trapped gas, pressure, and fullness) 1
• Initial evaluation should include assessment for:
  • Constipation (may indicate IBS-C or chronic constipation) 2
  • Food intolerances (particularly carbohydrate intolerances) 2
  • Alarm symptoms (vomiting, weight loss >10%, GI bleeding) 2
  • Risk factors for small intestinal bacterial overgrowth (SIBO) 2

Treatment Strategies Based on Underlying Mechanisms

1. Dietary Interventions

• Reducing fiber intake can decrease abdominal distension by limiting bacterial fermentation and gas production 2
• Low FODMAP (Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols) diet may be beneficial, but should be avoided in malnourished patients 2
• Identify and eliminate specific food intolerances through short-term (2-week) dietary restriction trials 2
• For suspected carbohydrate intolerance, consider hydrogen breath testing for lactose, fructose, or sucrose intolerance in patients who don't respond to dietary restrictions 2

2. Pharmacological Management

For Gas and Bloating:

• Peppermint oil may help reduce bloating and gas 2
• Antispasmodics can improve symptoms:
  • Antimuscarinic agents: dicycloverine hydrochloride, propantheline bromide, hyoscine butylbromide 2
  • Hyoscine butylbromide may be more effective when administered intramuscularly for long-term home use 2

For Associated Constipation:

• Osmotic laxatives (polyethylene glycol) 2
• Stimulant laxatives when osmotic agents are insufficient 2
• For severe cases, consider:
  • Rectal stimulants (glycerol suppositories) 2
  • Enemas (phosphate preparations progressing to high-volume saline washouts) 2
  • Transanal irrigation systems for refractory cases 2

For Associated Vomiting:

• 5-HT3 antagonists like ondansetron (may cause constipation) 2
• Consider venting gastrostomy (>20 French gauge) for persistent vomiting to decompress the stomach 2

For Bacterial Overgrowth:

• Antibiotics such as rifaximin (non-absorbable) or alternatives like amoxicillin, fluoroquinolones, or metronidazole 2

3. Behavioral and Psychological Interventions

• Diaphragmatic breathing exercises to reduce vagal tone and sympathetic activity 2
• Brain-gut behavioral therapies (BGBTs) including:
  • Cognitive behavioral therapy (CBT) 2
  • Gut-directed hypnotherapy 2
• These therapies are particularly helpful for abdominophrenic dyssynergia (APD), a condition where the diaphragm paradoxically contracts and abdominal wall muscles relax, leading to distension 2

Special Considerations

For Ascites-Related Distension

• Dietary sodium restriction and diuretic therapy are first-line treatments 2
• Anti-mineralocorticoid drugs (spironolactone, canrenone, K-canrenoate) up to 400 mg/day 2
• Loop diuretics (furosemide) should be combined with anti-mineralocorticoids in patients with long-standing ascites 2
• Large-volume paracentesis for grade 3 ascites (marked abdominal distension) 2

For Intestinal Pseudo-Obstruction

• Treatment should be directed at the main symptom, using minimal medications 2
• Avoid high doses of opioids and unnecessary surgery 2
• If oral feeding is unsuccessful and patient isn't vomiting, consider gastric feeding 2
• For persistent vomiting, a venting gastrostomy may reduce symptoms but can have complications (leakage, infection) 2

Treatment Algorithm

1. First-line approach:

   • Dietary modifications (reduced fiber, low FODMAP if appropriate) 2
   • Peppermint oil for mild symptoms 2
   • Diaphragmatic breathing exercises 2

2. If symptoms persist:

   • Add antispasmodics (hyoscine butylbromide, dicycloverine) 2
   • Consider antibiotics if SIBO is suspected 2
   • Initiate brain-gut behavioral therapies 2

3. For refractory symptoms:

   • Evaluate for mechanical causes requiring surgical intervention 2
   • Consider central neuromodulators for visceral hypersensitivity 2
   • For severe distension with vomiting, consider venting gastrostomy 2

Pitfalls and Caveats

• Avoid high-fiber diets in patients with significant distension as they may worsen symptoms 2
• Be cautious with opioids for pain management as they can cause narcotic bowel syndrome and worsen distension 2
• Venting gastrostomies can be effective but are associated with complications including leakage and infection 2
• Avoid medicalizing patients early in the course of illness (enteral access, suprapubic catheters) 2
• When using diuretics for ascites, dosage should not be increased earlier than 72 hours due to their slow effect 2