Bowel obstruction Flashcards
What are different types of vomiting associated with?
Haematemesis- vomiting blood from the stomach
Large volumes- intestinal obstruction
Faeculent vomit- low intestinal obstruction, gastrocolic fistula
Projectile vomit- gastric-outflow obstruction
Chronic nausea and vomiting with no abdominal symptoms- psychological
Early morning vomiting- pregnancy, alochol dependence, metabolic disorders (uraemia)
What are the most common causes of small bowel obstruction?
Adhesions
Hernias
Crohn’s
Intususseption
What are the features of small bowel obstruction?
central abdominal pain
nausea and vomiting
‘constipation’ with complete obstruction
abdominal distension may be apparent, particularly with lower levels of obstruction
Bowel obstruction symptoms & signs
Vomiting: undigested food=gastric outlet obstruction, bilous=upper SBO, faeculent=distal SBO
Pain: colicky, may be absent in long-standing obstruction
Constipation: may not be absolute in proximal obstruction
Distention
Tinkling bowel sounds
Dehydration
Central resonance to percussion, dull flanks
Scars: previous surgery –> adhesions
Palpable mass
No abdominal tenderness unless strangulation
Common causes of large bowel obstruction
Colon carcinoma
Diverticular disease
Sigmoid volvulus
Constipation
Bowel obstruction complications
Bowel wall: oedematous & distended –> vessels stretched + blood supply compromised –> strangulation –> ischaemia + necrosis
Proliferation of bacteria
Perforation of bowel
Symptoms develop gradually in large bowel obstruction & ileo-caecal valve incompetence
Bowel obstruction investigations
Bloods: FBC, U&E, amylase, LFTs
ABG
Urinalysis
Supine AXR: distended proximal bowel, absent gas distally
Erect CXR: fluid level in SBO, air below diaphragm if perforation
Contrast enema: differentiates obstruction/pseudo-obstruction, identify obstruction level & ileo-caecal competency
CT: indicate obstruction level, not always diagnose
