What is the treatment for a hard distended abdomen?

Treatment of Hard Distended Abdomen

Immediate management requires urgent assessment for life-threatening causes including bowel obstruction, perforation, or ischemia, followed by aggressive fluid resuscitation, nasogastric decompression, and source control through surgery when indicated. 1, 2, 3

Immediate Assessment and Stabilization

Critical Initial Steps

• Assess for signs of peritonitis or shock immediately: hypotension, tachycardia, fever, diffuse tenderness, guarding, rebound tenderness, or rigidity—these mandate urgent surgical consultation 1, 3, 4
• Examine for absent or hypoactive bowel sounds, which indicate paralytic ileus or complete obstruction 3, 5
• Perform digital rectal examination to exclude fecal impaction and assess for masses or blood 1, 2
• Check for masked liver dullness on percussion, which suggests free intraperitoneal air from perforation 1

Resuscitation Protocol

• Initiate aggressive IV fluid resuscitation with isotonic saline (0.9% NaCl) at 15-20 ml/kg/hour if signs of volume depletion or shock are present 2, 3
• Place nasogastric tube for gastric decompression in patients with obstruction, ileus, or severe distension 1, 3, 5
• Target urine output >0.5 ml/kg/hour as the goal of adequate resuscitation 3
• Insert urinary catheter to monitor output accurately 3

Diagnostic Workup

Imaging Studies (Priority Order)

• Obtain CT scan with IV contrast as the primary diagnostic modality to identify obstruction, perforation (extraluminal gas, intra-abdominal fluid), ischemia (abnormal bowel wall enhancement, pneumatosis, mesenteric venous gas), or masses 1, 2, 4
• Plain abdominal X-rays can show dilated bowel loops and help differentiate small bowel from large bowel obstruction, but CT is superior 1, 5, 6
• Ultrasound may be used as initial screening but has limited sensitivity 1

Laboratory Tests

• Complete blood count, comprehensive metabolic panel including electrolytes (potassium, magnesium, calcium), renal function, liver function, lactate, and C-reactive protein 1, 2, 3
• Elevated lactate suggests bowel ischemia and requires urgent surgical intervention 1, 4

Treatment Based on Etiology

Mechanical Obstruction with Peritonitis or Ischemia

• Immediate surgical intervention is mandatory for patients with signs of perforation, gangrene, or shock 1, 3
• Open or laparoscopic approach depends on hemodynamic stability: unstable patients require open surgery 1
• Resection with primary anastomosis if bowel is viable; resection with delayed anastomosis or stoma creation if ischemia, severe inflammation, or critically ill 1
• Broad-spectrum antibiotics must be initiated immediately 1:
  • For septic shock: Meropenem 1g q6h by extended infusion, Doripenem 500mg q8h by extended infusion, or Imipenem/cilastatin 500mg q6h by extended infusion 1
  • For critically ill without shock: Piperacillin/tazobactam 4g/0.5g q6h or 16g/2g continuous infusion 1
  • Continue antibiotics for 4 days if adequate source control in immunocompetent patients, up to 7 days if immunocompromised or critically ill 1

Paralytic Ileus (No Mechanical Obstruction)

• Conservative management with bowel rest, nasogastric decompression, and correction of electrolyte abnormalities 3, 6
• Correct hypokalemia, hypomagnesemia, and hypocalcemia aggressively as these worsen bowel dysmotility 3
• Reduce or eliminate opioid medications—consider peripheral mu-opioid receptor antagonists like methylnaltrexone if opioid-induced 1, 3
• Neostigmine 2-2.5mg IV over 3-5 minutes can be used for acute colonic pseudo-obstruction (Ogilvie's syndrome) with cardiac monitoring, but only after excluding mechanical obstruction 6
• Avoid antimotility agents (loperamide, opiates) when bowel dilatation is present 3

Chronic Small Intestinal Dysmotility

• If chronic symptoms with recurrent distension and no acute obstruction, consider underlying dysmotility disorder 1
• Dietary modifications: reduce fiber to decrease bacterial fermentation and gas production; consider low FODMAP diet if not malnourished 1, 7, 8
• Prokinetic agents may help but metoclopramide should be used cautiously due to risk of tardive dyskinesia 9
• Antimuscarinics like hyoscine butylbromide can reduce spasm-related pain 1
• Small bowel manometry or wireless motility capsule testing may be indicated for refractory cases to identify neuropathy versus myopathy 1

Perforated Viscus

• Urgent surgical repair is required 1
• For perforated peptic ulcer: laparoscopic/open suture repair with omental patch for small perforations; distal gastrectomy for large perforations near pylorus 1
• Antibiotics as per septic shock protocol above 1

Monitoring and Follow-up

• Monitor intra-abdominal pressure if concern for abdominal compartment syndrome—pressure >20 mmHg with organ dysfunction requires decompression 1
• Serial abdominal examinations every 4-6 hours to detect clinical deterioration 3, 4
• Repeat imaging if no improvement within 24-48 hours of conservative management or if clinical deterioration 1, 4
• Patients with ongoing signs of infection beyond 7 days of antibiotic treatment warrant diagnostic investigation for inadequate source control 1

Critical Pitfalls to Avoid

• Do not delay surgical consultation when peritonitis, ischemia, or complete obstruction is suspected—mortality increases with each hour of delay 4
• Do not encourage oral intake or large volumes of water in patients with obstruction or severe ileus—this worsens distension 3
• Do not close the abdomen under tension after laparotomy for severe intra-abdominal sepsis—leave open with negative pressure therapy to prevent abdominal compartment syndrome 1
• Do not assume functional bloating without excluding organic causes first, especially in patients with alarm features (weight loss, anemia, age >50 with new symptoms) 1, 7, 8