Pyloric Stenosis

Question 1

What is pyloric stenosis?

Answer 1

A narrowing of the opening from the stomach to the first part of the small intestine (the pylorus)

Question 2

When does pyloric stenosis typically present?

Answer 2

2-8 weeks of age

Question 3

What is the time of presentation irrespective of?

Answer 3

Gestational age

Question 4

What is the underlying pathology in pyloric stenosis?

Answer 4

Hypertrophy of the pyloric muscle causing gastric outlet obstruction

Question 5

What happens as a result of gastric outlet obstruction?

Answer 5

Gastric contents cannot empty into the duodenum

Question 6

How can all ingested foods and gastric secretions exit the body in pyloric stenosis?

Answer 6

By vomiting

Question 7

What are the risk factors of pyloric stenosis?

Answer 7

• C-section
• Preterm birth
• Bottle feeding
• First born
• Male gender
• Family history

Question 8

What are some symptoms of pyloric stenosis?

Answer 8

• Vomiting
• Hunger after vomiting
• Weight loss

Question 9

Describe the vomiting experienced in pyloric stenosis?

Answer 9

• Occurs within an hour of feeding
• Increasing in frequency and forcefulness over time until projectile
• Non-bilious
• May contain blood due to oesophagitis

Question 10

When will hunger after vomiting drop off?

Answer 10

When dehydration leads to loss of interest in feeding

Question 11

When can weight loss occur in pyloric stenosis?

Answer 11

When there is late presentation

Question 12

What are the late signs of pyloric stenosis?

Answer 12

• Dehydration
• Weight loss
• Malnutrition
• Jaundice

Question 13

How should a baby be examined for pyloric stenosis?

Answer 13

Test feed to calm the infant and allow abdominal examination

Question 14

What will abdominal examination show in an infant with pyloric stenosis?

Answer 14

• Gastric peristalsis

- Pyloric mass in RUQ

Question 15

What does gastric peristalsis look like?

Answer 15

A wave moving from left to right across the abdomen

Question 16

How does a pyloric mass appear?

Answer 16

Feels like an olive

Question 17

What imaging may be useful in pyloric stenosis and why?

Answer 17

USS to confirm diagnosis prior to surgery

Question 18

What might biochemistry results show in pyloric stenosis?

Answer 18

• Hypochloraemic metabolic alkalosis
• Hyponatraemia
• Hypokalaemia

Question 19

What can cause the abnormal biochemistry results?

Answer 19

Repeated vomiting of the stomach contents

Question 20

What are the differential diagnoses of pyloric stenosis?

Answer 20

• Gastro-oesophageal reflux

- Intussusception

Question 21

What is the initial priority in managing pyloric stenosis?

Answer 21

Correcting any fluid and electrolyte disturbance with IV fluids

Question 22

Suggest a fluid plan for the management of initial fluid electrolyte losses in pyloric stenosis

Answer 22

0.45% saline with 5% dextrose and 20mmol/L potassium chloride at 120ml/kg/day

Question 23

How should stomach contents be managed?

Answer 23

Withhold feeds and empty stomach with NGT

Question 24

What is the definitive treatment for pyloric stenosis?

Answer 24

Pyloromyotomy

Question 25

What does pyloromyotomy involve?

Answer 25

Division of the hypertrophied muscle down to, but not including the mucosa

Question 26

How can pyloromyotomy be performed?

Answer 26

As an open procedure via the periumbilical incision or laparoscopically

Question 27

How soon can the child be fed post-operatively?

Answer 27

Usually ~6 hours

Question 28

How soon can the child be discharged post-operatively?

Answer 28

~2 days

Question 29

What are the complications of pyloromyotomy?

Answer 29

• Perforation of mucosa

- Wound infection