Overview

• Hypertrophy (thickening) and narrowing of the pyloric sphincter.
  • Pyloric Sphincter → ring of smooth muscle that forms the canal between the stomach and the duodenum.**
• Typically presents in 2nd-4th week of life.
• Increasing peristalsis in stomach after feeding → food ejected into oesophagus → projectile vomiting.

Making Diagnosis

Clinical Features

• Projectile vomiting, typically 30 mins after feed.
  • Non-bilious → as the level of obstruction is proximal to the second part of the duodenum where bile enters the gastrointestinal tract. This is in contrast to malrotation and duodenal atresia.
• Hungry baby that is thin, pale and failing to thrive.
• Significant dehydration and electrolyte abnormalities.
• Palpable olive-shaped mass in upper abdomen → caused by hypertrophic muscle of pylorus.

Investigations

• Diagnosis → abdominal ultrasound to visualise thickened pylorus.
• Persistent Vomiting → hypochloraemic, hypokalaemic metabolic alkalosis.

Management Plan

• IV Fluid Resuscitation (INITIAL) → prior to surgery to correct fluid and electrolyte balance.
  • NBM (prior to surgery), NGT (for feeds).
• Laparoscopic Pyloromyotomy (DEFINITIVE) → incision is made in the smooth muscle of the pylorus to widen the canal allowing that food to pass from the stomach to the duodenum as normal.