2. Bronchiolitis
• Bronchiolitis is a viral illness affecting infants under the
age of two.
• Incidence is markedly seasonal with peak incidence
between November to March.
• The commonest cause is Respiratory Syncytial Virus
(RSV) in approximately 75% of cases. Adenovirus,
Metapneumovirus, Influenza and Parainfluenza may
also be responsible.
• Pathologically, there is bronchiolar obstruction caused
by oedema and mucus leading to overinflation,
atelectasis and impaired gas exchange.
3. Presenting Features
History Examination
Coryzal symptoms (peak illness at five
days)
Dry, wheezy cough
Wheeze
Difficulty in breathing
Cyanosis
Apnoeas
Poor feeding (dyspnoea associated)
Low oxygen saturations
Tachypnoea
Recession / tracheal tug
Widespread fine inspiratory crackles
Wheeze *
Fever > 38°C is not usually a feature **
* Absence of wheeze does not exclude the diagnosis
** Fever > 39°C should prompt careful examination for another cause
4. Admission Criteria
• Bronchiolitis is a clinical diagnosis – as is the requirement for
admission.
• The following features should prompt consideration of
admission:-
• Oxygen saturations < 94% in air
• Respiratory rate > 70 per minute
• Marked recession / respiratory distress / grunting respirations
• History of apnoeas
• Taking < 50% usual feeds / concerning hydration status
• Lethargic or appears unwell.
• Duration of illness is also a relevant factor. Peak of illness with
bronchiolitis is typically 4-5 days, therefore infants with moderate
symptoms presenting before this time should be considered for
admission.
5. High Risk Infants
• The following have increased risk of severe illness
and should have lower admission threshold-
• Infants < 6 week age
• Ex-preterm infants
• Chronic Lung Disease
• Congenital Heart Disease
• Immunodeficiency
• Trisomy 21 or other syndromic association
6. Investigations
• Nasopharyngeal aspirate (NPA)
• Pulse oximetry should be recorded on all patients.
• Chest radiography is not routinely required but should
be considered after a sudden clinical deterioration.
• Bloods tests are not routinely required.
• FBC/cultures may be performed if sepsis suspected
• Blood gases may be useful if advanced respiratory
support is being considered.
8. Oxygenation
• Supplemental oxygen should be initiated for
oxygen saturations 90% or below.
• Aim to keep oxygen saturation > 92%.
• Humidified head box oxygen should be used if
physically possible.
• In larger infants, nasal cannulae should be
used if requiring less than 35% FiO2 (1 L/min).
Otherwise, humidified facial mask oxygen will
be required.
9. Feeding
• Small, frequent sucking feeds may be used for
mild cases.
• Nasogastric feeds may be required if taking less
than 50% requirements or respiratory rate >60
or in supplemental oxygen.
• Intravenous fluids should be reserved for severe
illness with severe respiratory distress or when
nasogastric feeds are not tolerated.
• Restrict to 70% of maintenance due to possible
SIADH with RSV infection.
10. Nebulised Hypertonic Saline
• Prescribe on drug card as:
• 4ml of 3% sodium chloride AND 2.5mg salbutamol
eight hourly via jet nebuliser
• Hypertonic saline administration has been
demonstrated to decrease mean duration of admission
in mild/moderate acute viral bronchiolitis by around
one day3.
• Hypertonic saline therapy is generally well tolerated,
although acute bronchospasm remains a concerning
possible side effect.
• Therefore it is recommended that hypertonic saline be
co-administered with salbutamol.
11. Bronchodilators
• Adrenaline:
• adrenaline nebulisers may be effective in
reducing bronchiolitis admission rates during the
first twenty four hours.
• It appears that combined adrenaline and
dexamethasone reduce admission rates for 7
days after Emergency Department attendance.
• Routine use of adrenaline nebulisers in the
Emergency Department is not recommended
but may be considered as a Consultant or
Registrar decision.
12. • Salbutamol/Ipratropium - There is no
evidence to support routine use in
bronchiolitis.
• Bronchodilators can produce modest short-
term improvement in clinical features.
• A trial dose of inhaled bronchodilator may be
reasonable, with further therapy predicated
on response in the individual patient.
Bronchodilators
13. Outcome / Advice to Parents
• Cough may persist for 2-4 weeks
• There may be an increased chance of
wheezy episodes in the future
• Avoidance of cigarette smoke exposure is
important.