IO

Chapter 23: Intestinal Obstruction

Classification of Intestinal Obstruction

  • Type of Obstruction

    • Acute Obstruction: Common in the small bowel.

      • Types: Volvulus, Intussusception

    • Chronic Obstruction: Occurs over time, can be more complex.

    • Acute on Chronic: Often seen in large bowel obstructions.

    • Closed-loop Obstruction: A dangerous type where both ends are obstructed.

  • Site of Obstruction

    • Small Bowel: Includes duodenum, jejunum, ileum.

    • Large Bowel: Typically sigmoid colon or right colon.

Aetiological Classification

  • Dynamic Obstruction: Mechanical blockage preventing normal movement of contents.

  • Adynamic Obstruction: Resulting from loss of intestinal motility.

  • Causes of Dynamic Obstruction:

    • Intraluminal: Foreign bodies, fecal impaction, tumors.

    • Intramural: Strictures, cancers.

    • Extramural: Adhesions, hernias.

Common Causes of Intestinal Obstruction

  • Congenital Malformations: Including atresia, malrotation.

  • Acquired Conditions: Most commonly adhesions (especially post-surgery) and hernias.

  • Others: Volvulus, intussusception, cancers, inflammatory bowel disease, and infections.

Symptoms and Clinical Features

  • Common Symptoms:

    • Colicky abdominal pain that later becomes constant.

    • Abdominal distension due to trapped gas and fluid.

    • Vomiting (early in small bowel obstruction, late in large bowel obstruction).

    • Constipation or inability to pass flatus is a classic sign.

Diagnosis

  • Imaging: Plain X-rays can show air-fluid levels; CT scans provide greater detail of blockage and status of bowel wall.

  • Physical Examination:

    • Inspect for abdominal distension, visible peristalsis, or palpable mass.

    • Assess bowel sounds - increased initially then absent if strangulation occurs.

Complications

  • Strangulation: Compromises blood supply leading to ischemia.

  • Perforation: Can occur in obstructed, ischemic bowel leading to peritonitis.

  • Sepsis: As a result of bacterial translocation from the bowel to systemic circulation.

Treatment

  • Immediate Management:

    • Stabilization includes IV fluids, nausea control, and electrolyte correction.

    • Nasogastric tube placement to decompress intestinal contents.

  • Surgical Intervention:

    • Laparotomy may be necessary to relieve the obstruction.

    • Resection of non-viable bowel segments, repairs of hernias, or releases of adhesions.

Specific Conditions

  • Intussusception:

    • Telescoping of a segment of bowel causing obstruction, commonly found in children.

    • Characterized by intermittent abdominal pain, often described as a "sausage-shaped" mass on examination.

  • Volvulus:

    • Twisting of bowel about its mesenteric attachment.

    • Requires immediate surgical intervention to prevent ischemic necrosis of bowel.

  • Adhesions and Bands:

    • Most common in developed nations as a cause of obstruction.

    • Often caused by previous surgeries and may require laparoscopic or open adhesiolysis.

Prevention & Management of Recurrence

  • Surgical Techniques: Minimizing formation of adhesions with careful operative techniques, use of barrier products, and proper handling of tissues.

  • Postoperative Monitoring: For signs of obstruction recurrence, particularly following abdominal surgeries.

Summary Notes on Each Page

  • Page 1: Overview of classification and types of intestinal obstruction.

  • Page 2: Common causes and expected sites of obstruction. Mortality rates associated with various forms.

  • Page 3: Pathophysiological changes following an obstruction, including absorption disturbances and inflammatory responses.

  • Page 4: Changes in the bowel wall post-obstruction, progression to gangrene/perforation.

  • Page 5: Clinical features of intestinal obstruction – pain, vomiting, and distension.

  • Page 6: Diagnostic imaging techniques, particularly the utility of CT scans.

  • Page 7: Treatment protocols for managing confirmed intestinal obstruction cases.

  • Page 8: Specifics on types of duodenal atresia, malfunctions learned through operative cases and typical features.

  • Page 9: Identification and features associated with meconium ileus, especially in context with cystic fibrosis.

  • Page 10: Types and complications of intestinal atresia in neonates and general management protocols.

  • Page 11: Malrotation and its association with other congenital anomalies, along with management objectives.

  • Page 12: Common presentations of intestinal obstruction in newborns.

  • Page 13: Summary of meconium ileus treatments.

  • Page 14: Intussusception diagnosis and dynamics of management.

  • Page 15: Signs, symptoms, and management strategies for common forms and complications of intestinal obstruction.

  • Page 16-22: Review of detailed management strategies for intussusception, volvulus, and various forms of obstruction.

  • Page 23: Clinical examination points relevant to identifying intestinal obstruction.

  • Page 24: Recap on the classification, causes, presentation, diagnosis, and treatment of intestinal obstruction conditions.