Bronchiolitis is a common respiratory infection in children under 2 years old caused by viruses like respiratory syncytial virus. It typically causes symptoms like cough, wheezing, difficulty breathing and feeding. While generally mild and self-limiting, it can require hospitalization in some cases. Treatment focuses on supportive care with oxygen, fluids, and respiratory support if severe. Prevention efforts target handwashing and palivizumab prophylaxis in high-risk infants to reduce spread and complications of the infection.

1. Bronchiolitis
Dr Yog Raj Khinchi

2. Bronchiolitis
• LRI – Leading cause – morbidity & mortality in children
• Bronchiolitis –
- Most common serious LRTI needing hospital admission
- Pediatric burden of illness world wide
- Generally self limiting condition

3. Bronchiolitis: Definition
• Clinical Syndrome
• Acute onset of resp. symptoms: < 2 yrs age
• Initial symptoms: URT viral infections
• Fever, coryza, progresses in 4-6 days to
LRT involvement: Cough and wheezing

4. Bronchiolitis: Epidemiology
•  incidence due to - More premature infants & children with
chronic illnesses
• More common in children < 12 months
• > 50% affected children: 2 to 7 mo of age
• Infants < 6 months are at highest risk of clinically significant disease
• 2% to 3% of children require hospital admission
• Commonly in late autumn and early spring

5. Increasing hospitalization
Predisposing factors
• Infants in day care
• Exposure to passive smoke
• Crowding in the household
• Environmental and genetic factors do contribute to severity
of disease

6. Bronchiolitis: Etiology
• Viral
Most common: Respiratory syncytial virus (RSV)
Others: Influenza, parainfluenza
adenovirus, coronavirus, rhinovirus
• M. pneumonia: though isolated not recognized as etiological agent

7. Bronchiolitis: Pathophysiology
Sloughed epithelial cells Airway obstruction
neutrophils & lymphocytes
Complete / partial plugging of some Atelectasis /
airways overdistention
Ventilation and perfusion imbalance Hypoxemia
Once plugging of airway has occurred, treatment is only
respiratory support, O2 and time

8. Bronchiolitis: Clinical features
• Quite variable
• Nasal obstruction with or without rhinorrhea
• Cough - First irritating  tight cough
• Poor feeding after the initial onset of symptoms
• Apnea upto 20% in < 12 months with RSV
• Fever - higher than 39oC [adenovirus or influenza]

9. • Nasal flaring  Tachypnea  Chest retraction

10. Bronchiolitis: Clinical features…
• Respiratory distress
– Mild, moderate or severe
• Clinical features - Nasal flaring, tachypnea, expanded chest,
audible wheeze
• Auscultation - rales or rhonchi & poor air entry, prolonged
expiratory phase
• Other features - Conjunctivitis, rhinitis & otitis media
• Mild-to-moderate hypoxia - Pulse oximetry or arterial blood
gases

11. Bronchiolitis: Clinical classification
Mild, moderate, or severe
Based on
• Ability to feed
• Respiratory effort
• Oxygen saturation observed at admission

12. Investigations: Specific and supportive
• Complete blood count
• CXR
• Nasopharyngeal aspirate (NPA) -
RSV and viral culture
• Electrolytes – especially if needing IV fluids
• Blood culture – if temperature > 38.5°C
• Blood gases
Usually no lab tests needed in mild bronchiolitis

13. Chest X-ray
CXR shows:
• hyperinflation
• patchy infiltrates
– typically migratory
(post-obstructive atelectasis
&
peribronchial cuffing)

14. Bronchiolitis: Diagnosis
• A clinical diagnosis
• Infant with short prodrome of upper RTI
• Clinical finding
- audible wheezing
- wheezing with crackles
- respiratory distress with
- chest recession

15. Bronchiolitis: Differential diagnosis
• Congenital anomalies
vascular ring, congenital heart disease
• Gastroesophageal reflux
• Aspiration pneumonia
• Foreign body aspiration

16. Management
• Supportive care - mainstay of therapy
• Moderately ill infants - require supplementary O2
• IVF in young infants - tachypnea, partial nasal obstruction
& feeding difficulties
• Role of bronchodilators - Controversial

17. Oxygen
• Humidified oxygen ideal
• Supplemental oxygen
if SaO2 <94%, combination of clinically significant respiratory
distress, RR > 60/min, feeding difficulty
• Maintain SaO2 above 95%
• Use nasal prongs / face mask / hood / head box
• Hypoxaemia + / - distress, despite high O2 flow, require
ventilatory support.

18. Fluid Therapy
• Indications
– Nasal flaring, tachypnoea (>60/min), apnoeic
episodes, marked retractions, tiring during feeds
• Normal maintenance volumes
– N/2 or N/4 dextrose saline
• Fluid volumes increased up to 20%
– if frequent or persistent fever (>38.5°C) and/or
markedly increased respiratory effort
• Monitor serum electrolytes

19. Beta-agonist therapy and clinical outcome
• RCT - no clear utility for bronchodilators in bronchiolitis

20. Nebulized epinephrine
• Improvement in respiratory symptoms - inconsistent &
potentially short-lived
• May use nebulized epinephrine as a potential rescue
medication who are to be admitted

21. Systemic Corticosteroids In Bronchiolitis
• Data suggest moderate potential efficacy
• In higher doses -
 hospitalization rates &
improve symptoms at 4 hours in ED in
patients with mod to severe bronchiolitis

22. Bronchiolitis: Ribavirin
• Ribavirin - considered in severely immuno- compromised
developing lab confirmed RSV assoc. bronchiolitis

23. ICU management
Needed in the following category
• Progression to severe respiratory distress, especially in at-
risk group
• Apnoeic episodes
– Eg. associated with desaturation
or > 15 seconds duration
or frequent recurrent brief episodes
• Persistent desaturation despite oxygen
• ABG evidence of respiratory failure
– i.e. pO2 < 80mm Hg;
pCO2 > 50mm Hg;
pH < 7

24. Bronchiolitis: CPAP
• May benefit infants with bronchiolitis by stenting open the
smaller airways during all phases of respiration
• Prevents air trapping & obstructive disease
• As a constant stimulus in infants - propensity to experience
apnea
• Data though promising, without controlled trials, are
inconclusive

25. Discharge
• Minimal respiratory distress
• SaO2 > 90% in room air
– Except in chronic lung disease, heart disease, or other
risk factors
• Not received supplemental O2 for 10 hrs
• Minimal or no chest recession
• Able to take oral feeds

26. Complications
• Respiratory complications - most frequent
• Infectious complications - second most common,
• Cardiovascular, electrolyte imbalance
• Complication rates were higher in -
premature infants
congenital heart disease
other congenital abnormalities
• Infants 33-35 weeks GA
highest complication rates
longer hospital stay

27. Serious complications
• Respiratory failure
• Apnea
• Pneumothroax
– Among former premature infants
– congenital abnormalities
• Risk of serious bacterial infections in first month of life
regardless of RSV + / -

28. Prognosis
• Generally self limiting condition
• 2% to 3% of children require hospitalization
• Need for supplemental O2 based on SaO2 on admission and
predict length of hospital stay
• Beware of rapid deterioration in high risk group
• Death is uncommon even in high risk group

29. Prevention
• RSV cross-infection is common and serious
– but largely preventable
• Vaccine development for RSV has been slow
• RSV spread from nose/face/hands of another individual
– Frequent hand washing by nursing, medical, other staff
and parents minimize this problem
• Avoid nursing infants with bronchiolitis (RSV positive, or
awaiting RSV results) in rooms with high-risk infants
• Some studies reveal
– Efficacy of palivizumab prophylaxis in prevention of RSV
bronchiolitis in severely premature infants with BPD