Introduction
Upper respiratory infections are the most common illnesses of childhood: a young child has 6–8 colds a year. Most are viral and self-limiting; the skill is to spot the few that block the airway or need antibiotics.
Common upper respiratory infections
Complications of strep throat: peritonsillar abscess (quinsy: trismus, uvula pushed aside), acute rheumatic fever (2–4 weeks later) and post-streptococcal glomerulonephritis (1–2 weeks later).
Stridor: the child with a noisy upper airway
Stridor is a harsh inspiratory noise from narrowing at or above the larynx. In a child, 1 mm of oedema in a 4 mm airway cuts its area by more than half, because resistance rises with the fourth power of the radius falling.
Acute respiratory failure
Respiratory failure means the lungs cannot keep blood gases normal.
Why children tire quickly
- Narrow airways, a soft rib cage that sucks in (recession) instead of expanding, a diaphragm that fatigues, and a high oxygen use per kilogram.
- Young infants breathe mainly through the nose, so a blocked nose matters.
Signs
- Work of breathing: fast breathing, recession (subcostal, intercostal, sternal), nasal flaring, grunting, head bobbing, use of neck muscles.
- Effect on the child: agitation, then drowsiness; pallor or cyanosis; tachycardia.
- Danger signs of exhaustion: slowing breathing, less recession, a silent chest, falling consciousness, bradycardia (a pre-arrest sign).
Management
- Airway position, suction; high-flow oxygen (target SpO₂ 94–98%).
- Support breathing step by step: heated humidified high-flow nasal cannula → CPAP or non-invasive ventilation → intubation and mechanical ventilation.
- Treat the cause (bronchodilators, antibiotics, adrenaline for croup) and give fluids carefully.