Makindo Medical Notes

Bronchiolitis - A monoclonal antibody to RSV is available as a monthly IM injection for high-risk preterm infants, though it is expensive.

Aetiology

• Bronchiolitis is primarily caused by Respiratory Syncytial Virus (RSV), leading to inflammation in the small airways.

Epidemiology

• Most commonly affects infants aged 1-9 months, up to 2 years of age.
• More prevalent during winter months.
• A subset of affected infants may go on to develop asthma later in life.

Higher Risk Groups

• Congenital heart disease
• Neuromuscular disorders
• Immunodeficiency
• Chronic lung disease

Clinical Presentation

• Initial symptoms include coryzal symptoms (nasal congestion) for 1-3 days followed by a persistent cough.
• Additional findings: pale, sweaty, tired appearance, nasal congestion, crackles, and wheeze on auscultation.
• Signs of respiratory distress: grunting, nasal flaring, use of accessory muscles, tachypnea, and subcostal/intercostal recession.

Differential Diagnoses

• Air leak, pneumonia, Acute Respiratory Distress Syndrome (ARDS) from sepsis
• Foreign body aspiration
• Pulmonary oedema (secondary to myocardial failure or congenital heart disease)

Investigations

• Chest X-Ray (CXR): Shows hyperinflated lungs, but NICE recommends against routine X-ray in bronchiolitis as changes may mimic pneumonia. Consider CXR if intensive care is planned.
• Blood Gas Testing: Not routinely required. Perform capillary blood gas testing if the child has severe or worsening respiratory distress (when supplemental oxygen >50%) or suspected impending respiratory failure.

Prevention

• Palivizumab, a monoclonal antibody produced via recombinant DNA technology, is used to prevent RSV infections in high-risk infants (e.g., those with prematurity, congenital heart disease).

Management

• Home Care:
  • Slightly raise the head of the crib to ease breathing.
  • Treat fever (>37.4°C) with paracetamol; ibuprofen if the child is over 3 months.
  • Saline nasal drops before feeding to relieve nasal congestion.
  • Use a humidifier or create a steamy environment (e.g., in a bathroom with hot water running) to ease cough but avoid direct contact with hot water or steam.
  • Nasal aspirators can be used to gently clear mucus from the baby’s nose.
• Hospital Referral:
  • Immediate (999): If apnoea, severe respiratory distress (e.g., grunting, marked chest recession, respiratory rate >70 breaths/minute), central cyanosis, or persistent oxygen saturation <92% on air.
  • Consider Referral: Respiratory rate >60 breaths/minute, difficulty feeding (<50-75% of usual intake), clinical dehydration.
• General Management in Hospital:
  • Maintain hydration and give antipyretics.
  • Avoid antibiotics, hypertonic saline, nebulized adrenaline, salbutamol (albuterol in the US), montelukast, ipratropium bromide, and corticosteroids per NICE guidance.
  • Provide oxygen if saturation is <92% persistently.
  • Administer fluids via nasogastric or orogastric tube if oral intake is inadequate.
  • Consider CPAP for impending respiratory failure and upper airway suctioning if secretions obstruct breathing or feeding.
  • High-risk infants include those with cardiac/lung issues, age <6 weeks, or preterm birth.

Indications for Ventilation

• Progressive tachypnoea and increased work of breathing
• Lethargy or persistent/prolonged apnoea
• Worsening respiratory acidosis
• Increasing oxygen requirements

References

• NICE guidance on Bronchiolitis 2016