RDS

Question 1

Respiratory distress in the neonate

Answer 1

Signs of respiratory distress:

1. High RR (>60)
2. Laboured breathing
3. Chest wall recessions
4. Nasal flaring
5. Expiratory grunting (PAP)
6. Cyanosis (if severe)

Beware retinopathy of prematurity if on high O2 levels

Question 2

Causes of RDS

Answer 2

• Deficiency of surfactant (phospholipids and proteins produced by type II pneumocytes)
• Deficiency leads to widespread alveolar collapse and inadequate gas exchange
• poorly compliant, low- volume lungs, with ventilation–perfusion mismatching

Risk factors:
1. Male> F
2. Premature <28 weeks
3. Diabetic mothers
4. Genetic mutation of surfactant genes
5. C-section
6. Second born premature twin

Question 3

Presentation

Answer 3

At delivery or within 4 hours of birth, develop signs of respiratory distress:

• Tachypnoea (> 60 breaths/ minute)
• Nasal flaring
• Expiratory grunting

(results from a partially closed glottis and slows the decrease in end-expiratory volume in order to try and create a positive airway pressure during expiration and maintain functional residual capacity)

• Laboured breathing with chest wall recession (intercostal, sternal and subcostal retractions)
• Cyanosis if severe (due to right-to-left intra- and extra-pulmonary shunting)
• Reduced breath sounds
• Pale infant
• Diminished peripheral pulses
• Peripheral oedema, low urine output

Question 4

Investigations

Answer 4

Examination

Basic observations- may show low O2 saturations, tachypnoea, tachycardia

Blood gases- may show low pO2, high CO2

CXR: characteristic appearance: diffuse granular or ‘ground glass’ appearance of the lungs

Question 5

Management plan

Answer 5

Specific Interventions

Antenatal steroids administration
* IM Glucocorticoids may be given to the mother to stimulate foetal surfactant production
* Given between 23-34 weeks if preterm delivery is anticipated/ high risk

Provision of positive airway pressure to prevent atelectasis
* Nasal continuous positive airway pressure
* Nasal intermittent positive pressure ventilation
* High-flow nasal cannulae
* Endotracheal intubation and mechanical ventilation

Exogenous surfactant therapy
* Given directly into the lungs via endotracheal tube or catheter

Blood gas monitoring

Thermoregulation- thermoneutral environment

Fluid management- slightly negative water balance

Question 6

Complications and prognosis

Answer 6

Complications

• Endotracheal tube complications- displacement or misplacement, subglottic stenosis and post-extubation atelectasis
• Pulmonary air leak (rupture of overdistended alveolus)
• Bronchopulmonary dysplasia
• Pneumothorax

Prognosis

• Giving glucocorticoids in infants < 34 weeks significantly reduces:
• RDS
• Bronchopulmonary dysplasia
• Intraventricular haemorrhage

Giving exogenous surfactant and antenatal corticosteroids has lowered mortality and morbidity associated with RDS