Neonatal medicine - preterm

Question 1

What is the most common cause of respiratory distress in preterm infants?

Answer 1

Respiratory Distress Syndrome (RDS)

Question 2

Describe the pathophysiology of RDS

Answer 2

Surfactant deficiency, leading to widespread alveolar collapse + inadequate gas exchange (surfactant is secreted by type II pneumocytes)

Question 3

Describe the investigation of suspected RDS

Answer 3

CXR - characteristic ‘ground-glass’ appearance

Question 4

If preterm delivery is anticipated, which treatment is given to reduce the risk of RDS?

If the infant develops RDS after birth, which treatments are given?

Answer 4

Prophylactic treatment:
- Steroids (e.g. dexamethasone) are given to the mother to stimulate foetal surfactant production

Management of RDS after birth:

• Exogenous surfactant instilled via ETT
• Oxygen and ventilatory support

Question 5

Why is it necessary to be cautious with oxygen and artificial ventilation in the preterm infant?

Answer 5

• Oxygen can cause retinopathy of prematurity

- Artificial ventilation may precipitate pneumothorax (this can also happen in the term infant)

Question 6

What is bronchopulmonary dysplasia (BPD)?

Answer 6

• Babies born prematurely often require treatments to help with breathing, e.g. oxygen, artificial ventilation
• If infants still require these treatments at 36 weeks corrected age, they are said to have BPD

Question 7

Describe the presentation of apnoea of prematurity

Answer 7

A preterm baby presents with periods where breathing spontaneously stops for < 20 seconds, accompanied with bradycardia

Question 8

Describe the pathophysiology of apnoea of prematurity

Answer 8

Underdevelopment/immaturity of autonomic nervous system and brainstem, leading to dysfunctional regulation of breathing

Question 9

Describe the management of apnoea of prematurity

Answer 9

• IV caffeine

- Tactile stimulation during apnoeic episodes

Question 10

Describe the pathophysiology of necrotising enterocolitis (NEC)

Why is NEC important to recognise?

Answer 10

Bacterial invasion and ischaemia of the large bowel

NEC is the leading cause of death in preterm infants

Question 11

What are the clinical features of necrotising enterocolitis?

Answer 11

• Abdominal distension
• Bilious vomiting
• Bloody stools

Question 12

Describe the investigation of necrotising enterocolitis

Answer 12

Abdominal XR:

• Dilated loops of bowel
• Thickening of bowel wall
• Intramural gas

Question 13

Describe the management of necrotising enterocolitis

Answer 13

• NBM, parenteral nutrition
• IV broad spectrum antibiotics
• Laparotomy

Babies may also need ventilatory and/or circulatory support

Question 14

Which factors can increase the risk of SIDS?

Answer 14

• Prematurity
• Parental smoking
• Co-sleeping