Endoscopy and biopsy Flashcards
Upper GI endoscopy: diagnostic indications
Haematemesis/melaena Dysphagia Dyspepsia (>55yrs old + alarm symptoms or treatment refractory) Duodenal biopsy Persistent vomiting Iron deficiency (cancer)
Upper GI endoscopy: therapeutic indications
Treatment of bleeding lesions Variceal banding and sclerotherapy Argon plasma coagulation for suspected vascular abnormality Stent insertion, laser therapy Stricture dilatation, polyp resection
Upper GI endoscopy: pre-procedure
Stop PPIs 2wks pre-op if possible (pathology masking).
Nil by mouth for 6h before.
Don’t drive for 24h if sedation is used.
Upper GI endoscopy: procedure
Sedation optional, e.g. midazolam 1-5mg slowly IV (to remain conscious; if deeper sedation is needed, propofol via an anaesthetist (narrow therapeutic range)); nasal prong O2 (e.g. 2L/min; monitor respirations and oximetry).
The pharynx may be sprayed with local anaesthetic before the endoscope is passed.
Continuous suction must be available to prevent aspiration.
Upper GI endoscopy: complications
Sore throat
Amnesia from sedation
Perforation (<0.1%)
Bleeding (if on aspirin, clopidogrel, warfarin, or DOACs, these need stopping only if therapeutic procedure).
Upper GI endoscopy: duodenal biopsy
The gold standard test for coeliac disease.
Also useful in unusual causes of malabsorption, e.g. giardiasis, lymphoma, Whipple’s disease.
Sigmoidoscopy
Views the rectum and distal colon (to ~splenic flexure).
Flexible sigmoidoscopy has largely displaced rigid sigmoidoscopy for diagnosis of distal colonic pathology, but ~25% of cancers are still out of reach. It can be used therapeutically, e.g. for decompression of sigmoid volvulus.
Sigmoidoscopy: preparation
Phosphate enema PR.
Sigmoidoscopy: procedure
Learn from an expert.
Do PR exam first.
Do biopsies- macroscopic appearances may be normal, e.g. IBD, amyloidosis, microscopic colitis.
Colonoscopy: diagnostic indications
Rectal bleeding- when settled, if acute Iron deficiency anaemia (bleeding cancer) Persistent diarrhoea Positive faecal occult blood test Assessment or suspicion of IBD Colon cancer surveillance
Colonoscopy: therapeutic indications
Haemostasis (e.g. by clipping vessel) Bleeding angiodysplasia lesion (argon beamer photocoagulation) Colonic stent deployment (cancer) Volvulus decompression (flexi sig) Pseudo-obstruction Polypectomy
Colonoscopy: preparation
Stop iron 1wk prior
Discuss with local endoscopy unit bowel preparation and diet required.
Colonoscopy: procedure
Do PR first.
Sedation and analgesia are given before colonoscope is passed and guided around the colon.
Colonoscopy: complications
Abdominal discomfort Incomplete examination Haemorrhage after biopsy or polypectomy Perforation (<0.1%) Post-procedure: no alcohol, and no operating machinery for 24h.
Video capsule endoscopy (VCE)
To evaluate obscure GI bleeding and to detect small bowel pathology.
Use small bowel imaging (e.g. contrast) or latency capsule test ahead of VCE if patient has abdominal pain or symptoms suggesting small bowel obstruction.