2. Plan
• Definition
• Etiology
• Risk factors
• Mode of transmission
• Pathophysiology
• Clinical features
• Diagnosis
• Management
• Differentials
• Complications
• Preventions
• References
3. Definition
• Acute inflammation of the lower respiratory tract leading to mucosal
swelling and mucus deposits within bronchioles
• Occurs primarily in infants and young children (peak incidence 3 to 6
months); their tiny airways get easily blocked by inflammatory
exudate
4. Etiology
• Usually caused by viruses, mainly Respiratory Syncytial Virus (RSV)
• Other viruses:
- Rhinovirus
-Para influenza virus type 3
-Human Metapneumovirus
-Adenovirus
- Influenza
- Coronavirus
-Human bocavirus 1
5. Mode of transmission
• Mode of spread: direct droplet spread
• Winter epidemics in Europe and America (November – April)
6. Risk factors
• Non breastfed babies (maternal antibodies)
• Overcrowding e.g. day-care centres
• Age <6 months
• Exposure to cigarette smoke
• Prematures
7. Pathophysiology
• Bronchiolitis occurs when viruses infect the terminal bronchiolar
epithelial cells, causing direct damage and inflammation in the small
bronchi and bronchioles.
• Pathologic changes begin 18 to 24 hours after infection and include
increased mucus secretion, bronchiolar cell necrosis, and sloughing
• Lead to ciliary disruption, peribronchiolar lymphocytic infiltration and
submucosal oedema
8. Cont pathophysiology
• Edema, excessive mucus, and sloughed epithelial cells lead to
formation of inflammatory debri produces critical narrowing and
obstruction of small airways
• Decreased ventilation of portions of the lung
↓
Ventilation/perfusion mismatch
↓
Hypoxia.
9. Cont pathophysiology
During the expiratory phase, further dynamic narrowing of the airways
produces disproportionate airflow decrease and air trapping
↓
Increased work of breathing due to increased end-expiratory lung
volume and decreased lung compliance
• Recovery of pulmonary epithelial cells occurs after 3 – 4 days
• Inflammatory debris is cleared by macrophages
• Cilia take about 2 weeks to regenerate
10. Clinical features
1. HISTORY
• Begin with upper respiratory tract symptoms
• Coryza with rhinorrhea
• nasal congestion and/or discharge(thick nasal secretions)
• dry cough
• low grade fever ≤38.3ºC (usually transient)
• progressive breathlessness
• Feeding difficulty
11. Cont clinical features
2. PHYSICAL
-Respiratory distress(tachypnea, nasal flaring, grunting, retractions)
-Cyanosis
-Irritability
-High pitched wheezes expiratory more than in inspiratory
-Fine inspiratory crackles
-Hyperinflated chest(increase AP diameter)
-Tachycardia
-Palpable liver and spleen (from hyperinflation of the lungs and consequent
depression of the diaphragm)
12. Bronchiolitis severity score
• The bronchiolitis severity score(BSS) is an assessment scale used to
evaluate the severity of illness in infants
• Severe bronchiolitis indicated by persistently increased respiratory
effort (tachypnea; nasal flaring; intercostal, subcostal, or suprasternal
retractions; accessory muscle use; grunting), hypoxemia, apnea, or
acute respiratory failure .
• Infants and young children with severe disease require hospitalization
for frequent observation as well as respiratory and/or fluid support
13. SCORES 0 1 2 3
RR when patient quiet Normal
New born≤60
Infant≤40
Toddler 20-30
Mid dyspnoea
60-80
40—60
30-40
Moderate
81-99
60-80
40-60
Severe
More than 100
80
60
Oxygen saturation 93%
90%
90-93%
88%
86-89%
86%
I≤85%
General appearance Caml, no distres,
interactive
Mild irritable, easily
consoled
Difficult to console,
moderate irritable
Extremelly irritable
and cannot be
consoled
Accesory muscle use No retraction Mild retraction(
abdominal)
1 OF 4
Moderate(intera
coastal,subcostal with
increase work of
breath 2 OF 4
Severe retraction with
sub, inter,tracheal
retraction, nasal
flaring,see saw
breathing
3 or more
wheezing clear End expiratory
wheezing with
crackles
Diffuse expiratory
wheezing
Diffuse inspiratory and
exp wheewing with
absent breath sound
14. Diagnosis
1. Clinical presentation
2. Pulse-oximetry
3. Chest x-ray is not routinely indicated (esp. when in doubt)
4. CBC: the white blood cell and differential counts are usually normal
and are not predictive of bacterial superinfection or moderately raised
(10,000 - 15,000/μL), usually 50 - 75% lymphocytes
5. RSV antigen test from nasal swab (polymerase chain reaction, or
rapid immunofluorescence) is not routinely recommended in the
diagnosis of bronchiolitis.
15. Cont diagnosis
• Xtic finding on Chest X-ray support Dx include:
oIncreased lung vol with flat diaphragms.
oMild cardiomegaly.
oProminent vascular marking in a sunburst pattern originating at the
hilium.
oFluid seen in interlobar fissures & pleural effusions may be present.
16. Indications for hospitalization
1. Sick appearance, poor feeding, lethargy, or dehydration
2. Moderate to severe respiratory distress with one or more of the
following signs: nasal flaring; intercostal, subcostal, or suprasternal
retractions; respiratory rate >70 breaths per minute; dyspnea; or
cyanosis
3. Apnea; Hypoxemia with or without hypercapnia (arterial or capillary
carbon dioxide tension >45 mmHg)
5. Parents who are unable to care for them at home
17. Management nonsevere bronchiolitis
Infants and children usually can be managed in the outpatient setting
1. Supportive care includes maintenance of adequate hydration, relief
of nasal congestion/obstruction, and monitoring for disease progression.
2.Components of education and anticipatory guidance include:
-Proper techniques for sunctioning the nose: saline nose drops or spray
might help with congestion and runny nose.
-Encourage fluids : parents should breastfeed and encourage their child
to drink
18. Cont nonsevere management
• Antibiotics, cough medicines, decongestants, and sedatives are not
recommended cause can mask symptoms of low blood oxygen and
difficulty breathing.
• Antibiotics may be necessary if complication as bacterial infection,
like an ear infection(otitis media) or pneumonia
• Return to medical care immediately: apnea, cyanosis, poor feeding,
new fever, increased work of breathing, decreasing fluid intake
• Follow-up within one to two days, may occur by phone or at the office
19. Management of severe bronchiolitis
1. Respiratory support: most children require
-Nasal sunctioning
-Supplemental oxygen is provided to maintain SpO2 >90 to 92%.
-Infants are at risk for respiratory failure often receive a heated
humidified high-flow nasal cannula (HFNC) therapy and/or
continuous positive airway pressure (CPAP) before endotracheal
intubation.
20. Cont severe management
• HFNC also called high-flow warm humidified oxygen) and CPAP are
used to reduce the work of breathing, improve gas exchange, and
avoid the need for endotracheal intubation in children are at risk for
progression to respiratory failure
• Endotracheal intubation : infants who have worsening severe distress
despite a trial of HFNC and/or CPAP, who have hypoxemia despite
oxygen supplementation, and those with apnea may require
endotracheal intubation and mechanical ventilation
21. Cont severe management
2. Fluid management:
• Children may have difficulty maintaining adequate hydration because
of increased needs (related to fever and tachypnea) and decreased
intake related to respiratory distress.
• Exclusive parenteral fluid administration or feeding by NGT is
necessary to ensure adequate hydration and avoid the risk of aspiration
in infants and children who are hospitalized with moderate to severe
respiratory distress
22. INTERVENTIONS THAT ARE NOT ROUTINELY RECOMMENDED
• Inhaled bronchodilators
• Oral bronchodilators
• Systemic glucocorticoids
• Inhaled glucocorticoids
• Bronchodilators plus glucocorticoids
• Nebulized hypertonic saline
• Racemic epinephrine
• Chest physiotherapy: is discouraged because it may increase the distress
and irritability of ill infants
• Antibiotics: always caused by viruses
23. Discharge criteria
●Respiratory rate <60 bpm for age <6 months, <50 bpm for age 6 to 11
months, and <40 breaths per minute for age ≥12 months
●Caretaker knows how to clear the infant's airway
●Patient is stable while breathing ambient air
●Patient has adequate oral intake to prevent dehydration
●Resources at home are adequate to support the use of any necessary
home therapies
●Caretakers are confident they can provide care at home
●Education of the family is complete
25. Complication
1. Chronic obstructive airway disease
2. Respiratory failure
3. Heart failure
4. Secondary infection, such as bacterial pneumonia
5. Bronchiolitis obliterans (usually adenovirus)
6. Acute otitis media
26. Prevention
• Standard strategies to reduce the risk of bronchiolitis and
accompanying morbidity include:
• Hand hygiene (washing with soap or with alcohol-based rubs) to
minimize transmission of infectious agents
• Encourage breastfeeding
• Minimizing passive exposure to cigarette smoke
• Avoiding contact to individuals with respiratory tract infections
27. Take home message
• Bronchiolitis is an acute infectious inflammation of the bronchioles
resulting in wheezing and airways obstruction in children less than 2
years old
• It is cause by virus especially RSV and others virus us rhinovirus
• Management is just supportive
28. References
1. Nelson textbook of Paediatrics, 21th ed.
2. Uptodate 2018
3. Illustrated textbook of Paediatrics, Tom Lissauer and Graham
Clayton, 4th ed.
