RESPIRATORY CONDITIONS
Apnoea of Prematurity
A practical guide for paediatric registrars · Immature respiratory control in the preterm infant
BRADY/DESAT -
EXCLUDE OTHER CAUSES
Immature respiratory control
The brainstem respiratory centres and chemoreceptor responses are immature.
Blunted chemoreflexes
Immature CO₂ responses; in preterm infants, hypoxia can depress rather than stimulate breathing.
Upper airway instability
Poor pharyngeal tone leads to obstructive and mixed events.
Exaggerated inhibitory reflexes
Reflexes such as the laryngeal chemoreflex can provoke apnoea.
A diagnosis of exclusion
Sepsis, NEC, IVH, hypoglycaemia, anaemia, reflux and temperature all cause apnoea and must be excluded.
CLINICAL FINDINGS
- Preterm infant with recurrent pauses >20s, or shorter pauses with bradycardia and/or desaturation
- Onset after the first day of life
- Often mixed apnoea (obstructive + central)
- Between events the infant is well
- New or worsening apnoea is a red flag for an underlying illness
INVESTIGATIONS
- Look for an underlying cause: sepsis screen (FBC, CRP, culture), glucose, electrolytes/calcium
- FBC for anaemia; consider cranial ultrasound (IVH) and abdominal assessment (NEC)
- Review feeds/reflux, drugs, positioning and temperature
- Cardiorespiratory monitoring to characterise events
- Imaging is normal in AOP - used only to exclude other causes
COMPLICATIONS & RED FLAGS
- Recurrent hypoxaemia and bradycardia
- Red flag: apnoea in a term infant, or a sudden change in pattern → investigate for sepsis, NEC, IVH or a metabolic cause; don't assume AOP
- Apnoea persisting beyond the expected gestation warrants review
MANAGEMENT
Exclude the dangerous mimics first, then treat the immature control with caffeine and, where needed, airway support.
Exclude & Support
- First, exclude and treat underlying causes (sepsis, anaemia, hypoglycaemia, NEC, IVH, reflux, temperature)
- Cardiorespiratory monitoring; gentle stimulation for events; correct positioning
- Maintain SpO₂; treat anaemia
Caffeine
- Caffeine citrate is first-line: loading ~20 mg/kg, then ~5-10 mg/kg/day maintenance - confirm dosing against the ANMF (Australian Neonatal Medicines Formulary)
- How it works: a methylxanthine that blocks adenosine (A1/A2A) receptors - stimulating central respiratory drive, raising CO₂ sensitivity and improving diaphragmatic contractility
- Reduces apnoea and the need for ventilation; the CAP trial showed less CLD and better neurodevelopmental outcomes
- Also used to facilitate extubation
Respiratory Support
- CPAP or high-flow for obstructive/mixed apnoea (splints the airway, maintains FRC)
- NIPPV or ventilation for frequent severe events unresponsive to caffeine + CPAP
- Confirm resolution before discharge (observation off support/caffeine, per local policy)
- After stopping caffeine, continue cardiorespiratory monitoring for ~5 days before discharge - apnoea and bradycardia can recur
- Document each apnoea: duration, colour change, bradycardia/desaturation and the stimulation needed.
- Continuous SpO2/HR monitoring; positioning (avoid neck flexion; supervised prone only in a monitored cot).
- Caffeine as charted; feeding caution; keep warm.
- A rising frequency may signal sepsis or another cause - escalate.
How do you distinguish apnoea of prematurity from apnoea due to another cause - and what makes you investigate?
What is the evidence base (CAP trial) for caffeine, and what are its benefits beyond apnoea?
Why does CPAP help obstructive and mixed apnoea?
When is it safe to stop caffeine and discharge?
Take-home message: Apnoea of prematurity is recurrent pauses (>20s, or shorter with bradycardia/desaturation) from immature respiratory control, appearing after the first day in preterm infants and resolving by ~34-37 weeks. It is a diagnosis of exclusion - new or worsening apnoea should prompt a search for sepsis, NEC, IVH or a metabolic cause. Treat with caffeine (first-line, with neurodevelopmental benefits per the CAP trial) and CPAP/high-flow for obstructive events, after excluding and treating other causes.
For educational purposes only. Always align management to current ANZCOR/NRP guidelines and your local SCN/NICU or NETS protocols.