For Patients & General Readers

Acute bowel obstruction is a serious condition where food or stool cannot pass through your intestines. It can happen suddenly and requires prompt medical attention to prevent complications like tissue damage or infection. Anyone can experience it, but it's more common after abdominal surgery or with certain medical conditions.

Clinical Overview

Acute bowel obstruction is a mechanical or functional impairment of intestinal transit, leading to proximal luminal distension and distal decompression. It is a surgical emergency requiring prompt diagnosis and management to prevent ischemia, perforation, and sepsis.

Clinical Presentation

Abdominal pain, often colicky and crescendo-decrescendo in nature.
Nausea and vomiting, which can become feculent in distal obstructions.
Abdominal distension, particularly prominent in distal obstructions.
Inability to pass flatus or stool (obstipation).
Dehydration and electrolyte imbalances due to fluid losses.

Signs & Symptoms

Symptoms (Patient-Reported)

Severe abdominal pain
Feeling bloated or swollen
Nausea and vomiting
Loss of appetite
Inability to pass gas
Constipation or inability to have a bowel movement

Signs (Clinician-Observed)

Abdominal distension
Tender abdomen on palpation
Hyperactive bowel sounds initially, progressing to hypoactive or absent bowel sounds
Peritoneal signs (rebound tenderness, guarding) may indicate strangulation or perforation

Differential Diagnoses

Condition	Distinguishing Feature
Gastroenteritis	Typically presents with diarrhea, diffuse abdominal cramping, and often a viral prodrome, rather than the focal pain and obstipation of obstruction.
Mesenteric Ischemia	Characterized by severe, disproportionate pain out of proportion to physical findings, often with a history of cardiovascular risk factors. Bowel obstruction may be a consequence.
Appendicitis	Usually presents with periumbilical pain migrating to the right lower quadrant, fever, and localized tenderness. Obstruction is uncommon unless a phlegmon or abscess forms.
Diverticulitis	Typically causes left lower quadrant pain, fever, and changes in bowel habits. Obstruction can occur due to inflammation or stricture formation.
Pancreatitis	Presents with severe epigastric pain radiating to the back, nausea, vomiting, and elevated pancreatic enzymes. Can cause paralytic ileus, mimicking functional obstruction.
Bowel Perforation	Characterized by sudden, severe, diffuse abdominal pain, rigidity, and signs of peritonitis. Often a complication of obstruction, but can occur independently.

Red Flags — Seek Immediate Care

Signs of peritonitis (rigidity, rebound tenderness, guarding)
Feculent vomiting
Severe, unrelenting abdominal pain
Signs of systemic sepsis (fever, tachycardia, hypotension)

Key Investigations

Abdominal X-ray (plain films): may show dilated loops of bowel and air-fluid levels.
Computed Tomography (CT) scan of the abdomen and pelvis with oral and IV contrast: gold standard for diagnosing obstruction, identifying the level and cause, and assessing for complications.
Laboratory studies: CBC, electrolytes, BUN, creatinine, lactate, amylase, lipase.
Ultrasound: can be useful in specific populations (e.g., children with intussusception) or as a bedside tool.

Management Overview

Management focuses on fluid resuscitation, electrolyte correction, nasogastric decompression, and addressing the underlying cause. Surgical intervention is often required, particularly for complete obstructions, signs of ischemia, or perforation.

Disclaimer: This article is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional for diagnosis and treatment. TruelyserMD does not replace clinical judgement.