Prematurity Flashcards
What common problems are associated with prematurity?
- Respiratory distress syndrome
- Necrotising enterocolitis
- Infection-
- Hypoglycaemia
- Temperature control
- Retinopathy of prematurity
- Intraventricular haemorrhage
What is the problem in RDS?
Deficiency of surfactant
What is the role of surfactant?
Lowers surface tension
What is surfactant made up of?
A mixture of phospholipids and proteins
What excretes surfactant?
Type 2 pneumocytes of the alveolar epithelium
What does surfactant deficiency lead to?
Widespread alveolar collapse and inadequate gas exchange
What happens to the incidence of RDS with increasing prematurity?
Increases
Who is RDS common in?
Infants born before 28 weeks
In what gender does RDS tend to be more severe in?
Boys
Can you get surfactant deficiency at term?
Rare, but can occur in diabetic mothers
How can RDS be avoided?
Glucocorticoids given to mother antenatally if preterm delviery is anticipated
How does maternal administration of glucocorticoids help in RDS?
Stimulates foetus to produce surfactant
What has been a major advancement in the treatment of RDS?
Development of surfactant therapy
What is surfactant therapy made from?
Extracts of calf or pig lung
How is surfactant therapy administered?
Instilled directly into lung via tracheal tube
How effective is surfactant therapy in RDS?
Shown to reduce mortality from RDS by 40% without increasing morbidity rate
When do symptoms of RDS begin?
At birth or within 4 hours of birth
What are the clinical signs of RDS?
- Tachypnoea >60breaths/min
- Laboured breathing with chest wall recession and nasal flaring
- Expiratory grunting
- Cyanosis if severe
What causes expiratory grunting in RDS?
It is to try and create positive airway pressure during expiration and maintain functional residual capacity
What does the CXR shown in RDS?
Diffuse granular or ‘ground glass’ appearance of lungs
Air bronchogram
Heart border becomes indistinct or completely obscured with severe disease
How is RDS treated?
Raised ambient oxygen, may need to be supplemented with CPAP or artificial ventilation via tracheal tube
What do the ventilation requirements need to be adjusted on the basis of in RDS?
According to infants oxygenation, chest wall movements, and blood gas analysis
What can be used to wean infants from added oxygen therapy in RDS?
High-flow humidified oxygen therapy via nasal cannulae
What is necrotising enterocolitis?
A serious illness associated with bacterial invasion of ischaemic bowel wall