Endoscopy

 

• Upper GI endoscopy

  Overview

  • Aka oesophagogastroduodenoscopy (OGD), gastroscopy.
  • Allows visualisation of oesophagus, stomach, and proximal duodenum, with option for biopsies or therapeutic interventions.
  • Push enteroscopy uses longer scope to reach distal duodenum and proximal jejunum.

  Indications

  • Management of acute upper GI bleeding.
  • Suspected upper GI malignancy: iron-deficiency anaemia, dysphagia, dyspepsia with onset age >55, weight loss, epigastric mass.
  • Any persistent upper GI symptoms which don't respond to treatment.
  • Coeliac diagnosis.

  Preparation and procedure

  Anticoagulation and antiplatelets:

  • For procedures with high bleeding risk – endomucosal resection, EUS with FNA, dilation or stenting, treating varices – stop warfarin, clopiodgrel, and ticagrelor 5 days before, and DOACs 2 days before.
  • For biopsy, which has a lower bleeding risk, continue warfarin (if in range), clopiodgrel, and ticagrelor, and omit DOAC on morning of procedure.
  • NSAIDs and aspirin can be continued.

  Other considerations:

  • Stop PPIs 2 weeks before.
  • Fast from food from 6 hours before, and clear liquids from 2 hours before. Small sips with tablets are acceptable.
  • Topical throat anaesthesia ± IV sedation to reduce discomfort.

  Complications

  • Perforation
  • Bleeding
  • Respiratory depression from sedation.

• Lower GI endoscopy

  Allows visualisation of the large bowel with the option of tissue biopsy and various therapeutic procedures e.g. polypectomy, stenting, decompression.

  Methods

  • Sigmoidoscopy: goes as far as the splenic flexure. Can detects up to 75% of colorectal cancer.
  • Colonoscopy: can go as far as the terminal ileum.

  Indications

  • Suspected colorectal cancer: rectal bleeding (when settled), altered bowel habit in older people, iron-deficiency anaemia, positive FOB test, lesion seen on imaging.
  • Suspected IBD.
  • Bowel obstruction: stenting obstructions, dilation of strictures, decompression of volvulus.

  Contraindications

  • There are few absolute contraindications, and the choice to proceed depends on weighing up individual risks and benefits.
  • However, colonoscopy should be avoided if there is known perforation, or a condition which predisposes to perforation e.g. acute diverticulitis, fulminant colitis.

  Preparation

  GI preparation:

  • Ideally follow low-residue diet or clear fluids from day before. Fast from food from 6 hours before, and clear liquids from 2 hours before. Small sips with tablets are acceptable.
  • 'Bowel prep' is the process of clearing all faeces from the bowel. For colonoscopy, typical regimen involves sodium picosulfate in the morning and afternoon the day before. For sigmoidoscopy, phosphate enema may suffice.

  Anticoagulation and antiplatelets:

  • For procedures with high bleeding risk – polypectomy, dilation, or stenting – stop warfarin, clopiodgrel, and ticagrelor 5 days before, and DOACs 2 days before.
  • For biopsy, which has a lower bleeding risk, continue warfarin (if in range), clopiodgrel, and ticagrelor, and omit DOAC on morning of procedure.
  • NSAIDs and aspirin can be continued.

  For the procedure, sedate (e.g. midazolam) and give analgesia.