Paediatrics: Development, Dosing and Deterioration
Core concepts
Paediatric questions combine growth and development with acute care. Know the milestones by age, the normal ranges for vital signs and weight at each stage, and the pattern of primitive reflex appearance and disappearance. Understand the physiology of the neonate: thermoregulation, jaundice timing (physiological versus pathological), and feeding volumes. Master the assessment of the unwell child - the triad of work of breathing, behaviour, and circulation - and the recognition of dehydration by clinical signs. Respiratory disease dominates: bronchiolitis, croup, asthma, and pneumonia each have distinctive features and management.
Drug dosing is weight-based and questions test this explicitly. Know vaccine schedules conceptually and the contraindications to live vaccines. Understand the approach to failure to thrive, developmental delay, and the safeguarding issues that arise when history and examination do not fit.
Traps
Examiners exploit the child who looks well but has a red flag, such as a bulging fontanelle or a non-blanching rash. Beware of adult thresholds applied to children - a respiratory rate of 40 is normal in an infant. Distractors often describe a treatment given at an adult dose, or a test that is inappropriate for age. Do not forget that a child's condition can change within hours.
Rule of thumb
In any paediatric emergency, assess appearance first, then work of breathing, then circulation; a child who is interacting normally is rarely critically ill.
Worked example
A 6-month-old with a two-day history of coryza, wheeze, and mild subcostal recession, feeding at 75% of normal, has bronchiolitis. Management is supportive - oxygen if saturations fall, fluids, and observation; antibiotics and salbutamol are not indicated.