Bowel Obstruction

Jonny and Ed discuss the most important anatomy and principles need to understand the presentation, investigation and treatment of bowel obstruction.

 

Lecture by

Video Duration: 22 minutes

  • Bowel Obstruction
    Created by Dr Ed Wallitt
    General
    Epidemiology

    Common

    2 types:

    SMALL and LARGE bowel obstruction

    Pathology

    Simple - one obstructing point

    Closed loop - two obstructing points, without vascular compromise

    Strangulated - obstruction with vascular compromise

    Top three causes

    Small bowel obstruction:

    • Adhesions
    • Hernias

    Large bowel obstruction

    • Malignancy
    • Diverticular disease (inflammatory stricture)
    • Volvulus (sigmoid or caecal)
    Clinical Features
    Symptoms

    Small bowel obstruction: Usually a patient who has had previous abdominal surgery presenting with vomiting and central, colicky abdominal pain.

    Large bowel obstruction: Usually an older patient with abdominal distension and absolute constipation (no flatus or passing of faeces). Vomiting and nausea are not typical features.

    Signs

    Unwell patient. In large bowel obstruction the abdomen will be distended and tympanic.

    Investigations
    Cultures

    None

    Bloods

    None

    Imaging

    AXR

    • SBO - dilatation of small bowel loops > 3 cm (valvulae conniventes; lines pass all the way through)
    • LBO - dilatation of large bowel loops > 6 cm (haustra; lines do not pass all the way through)

    CT abdomen and pelvis: if the cause is not adhesions then CT may reveal the site/cause of the obstruction.

    Scopic/Biopsy

    If a malignant stricture is suspected this will require colonoscopy + biopsy.

    Functional

    None

    Treatment
    Conservative

    Supportive: NBM and NGT (if vomiting)

    Medical

    Analgesia, IVF

    Surgical

    BO caused by adhesions may resolve spontaneously, however surgery may be required to relieve the obstruction.