Bronchiolitis

Question 1

Define bronchiolitis.

Answer 1

Respiratory condition characterised by

Question 2

Explain the aetiology/risk factors for bronchiolitis.

Answer 2

RSV (75%): may be multiple causative agents (rhinovirus, parainfluenza, influenza or adenovirus).

Inflammation of the bronchioles with secretion of mucus, necrosis of ciliated epithelium, and oedema of the submucosa causing airway obstruction.

Question 3

What are risk factors for severe bronchiolitis?

Answer 3

Prematurity.

Chronic lung disease.

Congenital/acquired lung disease.

Congenital heart defects (CHD)

Immunodeficiency.

Family history of atopic disease.

Breastfeeding and parental avoidance of smoking are protective.

Question 4

Summarise the epidemiology of bronchiolitis.

Answer 4

Most common LRTI in infants, especially 3–6 months.

Winter epidemics: 3% infants are admitted to hospital.

Question 5

What are the presenting symptoms of bronchiolitis?

Answer 5

Coryzal Sx preceeding:

Dry, wheezy cough

SOB

Expiratory wheeze

Fever

Poor feeding

Question 6

What are the signs of bronchiolitis?

Answer 6

General: Pyrexia. Tachycardia, irritability

Resp: Tachypnoea, subcostal/intercostal recessions, nasal flaring, grunting, expiratory wheeze, fine crepitations.

Severe: Cyanosis + lethargy.

Question 7

What is the admission criteria for bronchiolitis?

Answer 7

Difficulty feeding/ inadequate fluid intake: 50-75% normal volume

Respiratory distress (RR > 60, grunting)

O2 sats <92 in <6w or <90 in >6w

Apnoea

If <2m lower threshold as deteriorate quick

Question 8

What are investigations for bronchiolitis?

Answer 8

Clinical dx

Can confirm with NPA

CXR (if signif resp distress to exclude pneumonia)

Question 9

What is the management plan for bronchiolitis?

Answer 9

Supportive management:

Nasal O2

NG fluids/ feeds

Consider CBG with worsening respiratory distress

Consider CPAP in children with impending respiratory failure

Question 10

What treatments should not be used for bronchiolitis?

Answer 10

Do not use any of the following to treat bronchiolitis in children:

• Antibiotics
• Hypertonic saline
• Adrenaline (nebulised)
• Salbutamol
• Montelukast
• Ipratropium bromide
• Systemic or inhaled corticosteroids

Question 11

What can be used as preventative measures for infants with congenital or acquired lung disease, CHD or immunodeficiency?

Answer 11

Palivizumab (RSV monoclonal antibody)

Question 12

What are possible complications for bronchiolitis?

Answer 12

Mortality 0.2%, intensive care unit admission 2.7% and need for ventilatory assistance 1.5%.

Question 13

What is the prognosis for bronchiolitis?

Answer 13

Difficulty breathing, wheeze + poor feeding.

Persistent cough + recurrent viral-induced wheeze recur in 20% of infants (up to 60% of those hospitalised).

Recurrent wheeze is more common in first 5 years after RSV bronchiolitis, but conflicting evidence as to whether RSV bronchiolitis predisposes to asthma.