Hypertrophic pyloric stenosis – Pyloromyotomy

Introduction
Infantile hypertrophic pyloric stenosis is one of the most common causes of gastric outlet obstruction in newborns, and its aetiology remains unknown. Affected infants usually present between two weeks and two months after birth, with projectile vomiting after feeding. The pathology involves thickening and hypertrophy of the pyloric muscle, leading to obstruction of the outlet from the stomach to the duodenum, resulting in vomiting. Affected infants may subsequently experience dehydration, electrolyte imbalance and/or a rapid decline in weight. Surgery is required to address the pyloric muscle hypertrophy.

Surgical procedure
A pyloromyotomy can be performed through either open or laparoscopic (keyhole) surgery, with the doctor choosing the method based on the child's situation. Whether the surgery is open or laparoscopic, the child will be given a general anaesthetic.
In open surgery, the doctor makes an incision in the abdomen to locate the thickened pylorus, and then cuts the pylorus muscle to relieve the gastric outlet obstruction. Laparoscopic surgery is performed through three small incisions (each about 3 to 5 millimetres) in the abdomen, and it is possible to switch to open surgery during the operation.

Risk

1. Pyloric sphincter incision leakage
2. Incomplete pyloromyotomy (failure to relieve obstruction)
3. Wound infection
4. Bleeding wound
5. Incisional hernia

Uncommon risks

1. Damage to intra-abdominal organs resulting in severe bleeding
2. Complications of general anaesthesia

Pre-operative preparation
The child may require further investigations for diagnosis, such as ultrasound or other radiological examinations. If hypertrophic pyloric stenosis is confirmed, the child will be made nil by mouth and will require intravenous fluids and electrolytes to improve dehydration and electrolyte imbalance.

Post-operative care
The child may experience vomiting for a few days after surgery, but this usually lessens and improves over time. The child can generally resume feeding after surgery, and the doctor will increase the feeding amount as appropriate.

Follow-up appointment
The child can generally be discharged a few days after the operation and an outpatient appointment will be scheduled for a follow-up.

Notes
This leaflet is for reference only and does not list all possible complications. Other unforeseen complications may occur. The actual risks may differ for certain categories of patients. Please contact your doctor for more information.

Source: https://www.ekg.org.hk/pilic/public/surgery_pilic/paedsurg_pyloromyotomy_0319_chi.pdf