Bowel Flashcards
Define ileus. Give some examples.
Decreased motor activity of GI tract
No bowel sounds
e.g. post-op (due to nervous irritation or electrolyte imbalances), long-term constipation (learning difficulties –> pseudo-obstruction/paralytic ileus)
Describe the features of small bowel obstruction. Give some examples of causes.
> 3cm
Early vomiting, late absolute constipation
Mild distension
Colicky pain
Causes: adhesions, hernias, tumours, inflammation
Describe the features of large bowel obstruction. Give some examples of causes.
> 6cm, >9cm (caecum)
Early absolute constipation, late faeculant vomiting
Significant distension
Causes: colorectal cancer, diverticular strictures, hernias, volvulus, pseudo-obstruction
What are the signs on examination of bowel obstruction?
Dilated loops of bowel
Absence of gas distal to obstruction (most commonly absence of gas in rectum)
Tinkling bowel sounds
Contrast large bowel obstruction with a competent and incompetent ileocaecal valve.
Competent = distension of large bowel and caecum with relatively normal small bowel –> high risk of colonic perforation (no mechanism to lower luminal pressure)
Incompetent = dilatation of both small and large bowel, colon distal to obstruction collapsed and free of gas –> lower risk of colonic perforation
Define volvulus.
Twisting of organ around mesentery, causing obstruction.
Enclosed bowel loop dilates and perforates or causes ischaemia of proximal bowel (due to venous dilatation and oedema)
Restricted to either sigmoid or caecum.
Most common is sigmoid (coffee bean sign towards RUQ due to dilatation of proximal bowel).
Caecal volvulus less common (mobile caecum on right side with distal colon “collapse”)
What is toxic megacolon?
Acute deterioration in ulcerative colitis
Colonic dilatation, oedema, pseudopolyps
AXR not gold standard for detecting infection/inflammation (but may see some acute/chronic signs)
Give some causes of perforation.
Peptic ulcers Diverticula Tumour Obstruction Trauma Iatrogenic (laparoscopic procedures have gas remain for a few days post-op)
What is the management of small bowel obstruction?
NG tube (decompress bowel, reduce risk of perforation)
Fluids
CT scan
Surgery/wait and see/drip and suck
What is the management of large bowel obstruction?
NG tube if vomiting
Fluids
CT scan (NG tube important to prevent aspiration whilst lying supine for the scan)
Surgery/wait and see
What is the management of volvulus?
Sigmoid volvulus:
Call surgical registrar —> ?CT scan, flatus tube to decompress, ?surgery
Caecal volvulus:
CT scan, surgery
What is the management of suspected perforation?
CT scan
Give some differentials for haematemesis and melaena?
- peptic ulcer disease
- erosive gastritis
- Mallory-Weiss tear
- oesophagitis
- ruptured oesophageal varices
- vascular abnormalities
- oesophageal/gastric neoplasm
- perforation
What is the relevant history in haematemesis and melaena?
Differentiate haematemesis from haemoptysis
- hypovolaemia symptoms
- Rx = NSAIDs, excessive alcohol, iron
- FHx = bleeding disorders, gastric cancer
- PMHx = previous upper GI bleeds
What are the general and specific examinations in haematemesis and melaena?
GENERAL
- anaemia
- jaundice
- clubbing
- lymphadenopathy
- skin: bruises, pupura
- cachexia
SPECIFIC
- rigid abdomen
- epigastric tenderness
- epigastric mass
- liver disease sequelae
- Gray-Turner’s
- Boerhaave’s syndrome