Makindo Medical Notes

Exclude functional non mechanical causes such as diabetic gastroparesis. Severe gastric outlet obstruction in adults is a serious condition that requires prompt diagnosis and intervention to prevent complications and improve outcomes.

About

• Gastric outlet obstruction which in the past was mainly benign due to PUD is now more commonly malignant in adults

Causes

• Malignancy - Pancreatic cancer, ampullary, gastric, duodenal, cholangiocarcinoma
• Scarring and stenosis from Peptic ulcer disease with Helicobacter pylori
• Foreign body: bezoar
• Congenital pyloric stenosis seen in babies

Clinical

• Vomiting immediately postprandial
• Dyspepsia from Peptic ulcer disease
• Vomiting is non-bilious, Weight loss, cachexia
• Succussion splash > 4 hrs after eating

Investigations

• FBC : anaemia U&E: Dehydration/AKI
• Low K seen late e.g. after 2-3 weeks
• Low Cl Low K High HCO₃^- metabolic alkalosis
• Urine may be paradoxically acidic
• Abdominal X-rays: May show a distended stomach with an air-fluid level.
• Nasogastric aspirate > 200 mls after fasting overnight
• Barium swallow: Reveals delayed gastric emptying and can show the location of the obstruction.
• Endoscopy: Allows direct visualization of the obstruction, and biopsy can be taken if malignancy is suspected.
• Staging CT abdomen: Useful for identifying the underlying cause, such as a tumour or external compression.

Management

• IV Rehydration and fluid and electrolyte replacement
• PPI for ulcer disease and Helicobacter eradication
• Pyloroplasty: For benign strictures, pyloroplasty can widen the gastric outlet.
• Partial gastrectomy once fit for surgery or gastrojejunostomy may be performed if the obstruction is inoperable due to advanced cancer.
• Self-expanding metallic stents can be placed endoscopically to relieve obstruction in cases of malignancy.
• Chemotherapy or Radiotherapy: For malignancy, to shrink tumours and relieve obstruction.