🚨 RIF tenderness with radiological evidence of caecal distension and distal colonic obstruction is a red flag for imminent caecal perforation and peritonitis. This follows Laplace’s Law — the greatest wall tension occurs where the bowel diameter is largest (the caecum). ⚠️

🩺 Initial Management of Large Bowel Obstruction
ABC, IV fluids 💧: 3–4+ L/day (reduce if heart failure). Bloods 🧪: Send urgently; correct electrolytes and monitor U&E. NG tube ➡️ decompression: Insert if vomiting. Urinary catheter: Replace losses accurately. Analgesia & Antiemetic: Cyclizine preferred; avoid metoclopramide. Monitor labs: Acidosis, lactate, rising WCC, CRP = suspect ischaemia. Imaging: Erect/supine AXR; CXR to exclude perforation (free air). CT Abdomen: Gold standard → identifies level, cause, complications. Functional causes: Stop causative drugs (opioids, anticholinergics), correct K⁺/Ca²⁺/Mg²⁺. Sepsis management: Broad-spectrum antibiotics, consider HDU/ICU. Physical causes: Surgical intervention often required.

🩺 Initial Management of Large Bowel Obstruction

ABC, IV fluids 💧: 3–4+ L/day (reduce if heart failure).
Bloods 🧪: Send urgently; correct electrolytes and monitor U&E.
NG tube ➡️ decompression: Insert if vomiting.
Urinary catheter: Replace losses accurately.
Analgesia & Antiemetic: Cyclizine preferred; avoid metoclopramide.
Monitor labs: Acidosis, lactate, rising WCC, CRP = suspect ischaemia.
Imaging: Erect/supine AXR; CXR to exclude perforation (free air).
CT Abdomen: Gold standard → identifies level, cause, complications.
Functional causes: Stop causative drugs (opioids, anticholinergics), correct K⁺/Ca²⁺/Mg²⁺.
Sepsis management: Broad-spectrum antibiotics, consider HDU/ICU.
Physical causes: Surgical intervention often required.

📖 About

LBO is a common acute surgical emergency in the elderly.
Presentation can be subtle in patients on steroids or with immunosuppression.
Untreated obstruction → perforation (often caecal) → faecal peritonitis → high mortality.

🧬 Aetiology

Progressive dilatation ↑ wall tension → vascular compromise, ischaemia, and perforation.
Perforation most often occurs at the caecum (largest diameter).

🔎 Causes

Luminal: Colorectal tumour, polyp, faecal impaction.
Mural: Strictures from malignancy, ischaemia, diverticulitis, radiation, pseudo-obstruction (Ogilvie’s).
Extramural: Hernia, volvulus (sigmoid or caecal), intussusception.

👩‍⚕️ Clinical Features

Symptoms: Colicky abdominal pain, progressive distension, absolute constipation/obstipation.
Signs: Guarding, peritonism, sepsis, shock. Elderly may present late and collapse suddenly with perforation.

🧪 Investigations

Bloods: FBC, U&E, ESR/CRP. Raised lactate → suggests ischaemia/necrosis.
ECG: Look for AF or MI (can complicate perioperative care).
AXR: Dilated peripheral colon, “cut-off sign”, haustra not crossing full lumen.
CXR: Free subdiaphragmatic air → perforation.
CT with contrast (preferred): Defines obstruction site, cause, complications, metastases.

📊 Comparison: Small vs Large Bowel Obstruction

Feature	Small Bowel	Large Bowel
Abdominal Pain	Early, colicky, central	Variable; may be dull or colicky
Vomiting	Early, bilious → faeculent	Late feature
Constipation	Late sign	Early & complete; overflow diarrhoea possible
Distension	More marked distally	Marked; especially sigmoid/caecum
Bowel Sounds	“Tinkling”, high-pitched	Varied; often absent if severe
AXR	Central loops, valvulae conniventes across full width	Peripheral, haustra not spanning full width
Common Causes	Adhesions, hernia, Crohn’s	Colorectal cancer, sigmoid volvulus, diverticular stricture

💊 Management

Resuscitation: IV fluids, electrolytes, catheterisation.
NG decompression: If vomiting or aspiration risk.
Antibiotics: Gram-negative + anaerobic cover (perforation/sepsis).
Surgery: Indicated if peritonitis, ischaemia, perforation. Options:
- Right hemicolectomy for caecal pathology
- Hartmann’s procedure for sigmoid perforation/stricture
- On-table stenting or resection in malignancy
Palliative care: In frail or metastatic disease → stenting, defunctioning stoma, or conservative care.

📚 References

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Colonic (Large bowel) Obstruction