Bronchiolitis is a common respiratory infection in children under 2 years old caused by viruses like respiratory syncytial virus. It presents with symptoms of cough, wheezing, difficulty breathing and feeding. Risk factors include premature birth, exposure to tobacco smoke and attendance at daycare. Diagnosis is clinical and treatment is supportive with oxygen, fluids and respiratory support if severe. Prevention focuses on handwashing and palivizumab prophylaxis in high risk infants to reduce spread of the virus. Prognosis is generally good even in high risk groups though complications can include respiratory failure.

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