Synopsis
Recognise mechanical obstruction of the distal stomach or proximal duodenum, correct aspiration, volume and electrolyte threats, distinguish benign scarring from malignancy through imaging and biopsy, and select endoscopic or surgical relief with nutritional planning.
- Gastric outlet obstruction is a mechanical block at the antrum, pylorus or proximal duodenum; retained food and delayed emptying alone do not define its cause.
- Gastric, duodenal and pancreatic malignancy must be considered in an adult with new obstruction, especially with weight loss, anaemia, jaundice, a mass or progressive course.
- Benign causes include peptic-ulcer scarring, inflammatory oedema, Crohn's disease, pancreatitis or pseudocyst, bezoar and postoperative or anastomotic stenosis.
Key red flags
Coughing, hypoxaemia, altered consciousness or copious supine vomiting signals airway danger. Sit upright, use suction and seek anaesthetic support before sedation or transfer.
Investigation priorities
Quantify vomiting-related depletion and guide safe fluid replacement.
Management branches
Persistent vomiting, distension or imaging confirms a functionally important gastric outlet blockage.
- Keep nil by mouth, elevate the head, assess aspiration and insert venous access; use nasogastric decompression when indicated with position and output documented.
- Replace isotonic fluid, chloride, potassium and magnesium according to serial laboratory, ECG, urine output and renal findings rather than a fixed generic bag sequence.
Key medicines
Proton-pump inhibitor for peptic inflammatory obstructionUse a named full-dose formulary PPI through an available route while active ulcer inflammation is treated, then define duration from endoscopic healing, H. pylori status and whether fixed scarring remains.
Prokinetic treatmentDo not prescribe while a mechanical gastric outlet obstruction is present; reconsider only after anatomy is patent and a separate motility disorder is objectively supported.