What is the approach to diagnosis and management of acute bronchiolitis in infants and young children, particularly those with a history of wheezing or asthma?

Approach to Diagnosis and Management of Acute Bronchiolitis

Diagnosis

Bronchiolitis is a clinical diagnosis based solely on history and physical examination—do not order routine chest radiographs, viral testing, or laboratory studies. 1, 2, 3

Clinical Presentation to Identify

• Typical features: Rhinorrhea, cough, crackles, wheezing, and signs of respiratory distress in infants under 12 months 4
• Respiratory assessment: Count respiratory rate over a full minute (tachypnea ≥70 breaths/minute indicates increased severity risk) 1
• Work of breathing indicators: Nasal flaring, grunting, intercostal/subcostal retractions 1

When Diagnostic Testing May Be Considered

• Chest radiographs are not routinely indicated because approximately 25% of hospitalized infants have radiographic atelectasis or infiltrates that are often misinterpreted as bacterial infection 1
• Viral testing may have a role only in reducing hospital transmission, not for clinical management 4

High-Risk Infants Requiring Closer Monitoring

• Age <12 weeks 1, 2, 3
• History of prematurity 1, 2, 3
• Hemodynamically significant congenital heart disease 1, 2, 3
• Chronic lung disease/bronchopulmonary dysplasia 1, 2, 3
• Immunodeficiency 1, 2, 3

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Management: Supportive Care Only

The cornerstone of bronchiolitis management is supportive care alone—avoid all routine pharmacologic interventions. 1, 3

Oxygen Therapy

• Administer supplemental oxygen only if SpO2 persistently falls below 90% 1, 2, 3
• Goal: Maintain SpO2 ≥90% with standard oxygen delivery 1, 2
• Discontinue oxygen when: SpO2 ≥90%, infant is feeding well, and has minimal respiratory distress 1, 2
• Avoid continuous pulse oximetry in stable infants—it may lead to less careful clinical monitoring, and serial clinical assessments are more important 1, 3
• Do not treat based solely on pulse oximetry readings without clinical correlation, as transient desaturations can occur in healthy infants 1, 3

Hydration and Feeding Management

• Continue oral feeding if: Respiratory rate <60 breaths/minute with minimal nasal flaring or retractions 1
• Transition to IV or nasogastric fluids if: Respiratory rate ≥60-70 breaths/minute, as aspiration risk increases significantly at this threshold 1, 3
• Use isotonic fluids specifically because infants with bronchiolitis frequently develop syndrome of inappropriate antidiuretic hormone (SIADH) secretion, placing them at risk for hyponatremia with hypotonic fluids 1, 3

Airway Clearance

• Use gentle nasal suctioning only as needed for symptomatic relief 1, 2
• Avoid deep suctioning, as it is associated with longer hospital stays in infants 2-12 months of age 1
• Do not use chest physiotherapy, as it lacks evidence of benefit 1, 5

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What NOT to Do: Avoid Non-Evidence-Based Interventions

Bronchodilators

Do not use bronchodilators routinely 1, 2, 3, 6

• A carefully monitored trial of α-adrenergic or β-adrenergic medication may be considered, but should only be continued if there is a documented positive clinical response 1, 2
• Most studies show no benefit, and routine use increases healthcare costs without improving outcomes 6, 5

Corticosteroids

Do not use corticosteroids routinely, as meta-analyses have shown no significant benefit in length of stay or clinical scores 1, 2, 3, 6

Antibiotics

Antibacterial medications should only be used with specific indications of bacterial coinfection (e.g., acute otitis media or documented bacterial pneumonia) 1, 2, 3

• Fever alone does not justify antibiotics, as the risk of serious bacterial infection in febrile infants with bronchiolitis is <1% 1, 3
• The risk of serious bacterial infection in infants with bronchiolitis is very low 1, 4

Other Non-Recommended Therapies

• Ribavirin should not be used routinely, but may be considered in highly selected situations such as documented RSV bronchiolitis with severe disease or high-risk patients 1
• Hypertonic saline is not routinely recommended in current AAP guidelines, though some evidence suggests potential benefit 7, 4

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Special Considerations for Infants with History of Wheezing or Asthma

The presence of wheezing does not change the management approach for acute bronchiolitis—supportive care remains the standard. 1, 3

• Infants hospitalized with bronchiolitis are more likely to have recurrent wheezing as older children compared to those who did not have severe disease 8
• It is unclear whether severe viral illness early in life predisposes children to develop recurrent wheezing or if infants who experience severe bronchiolitis have an underlying predisposition to recurrent wheezing 8
• For children with chronic cough post-bronchiolitis, manage according to pediatric chronic cough guidelines, using 2 weeks of antibiotics targeted to common respiratory bacteria for wet/productive cough without specific cough pointers 3

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Prevention and Education

For High-Risk Infants

• Consider palivizumab prophylaxis for high-risk infants, administered in 5 monthly doses (15 mg/kg per dose intramuscularly), typically starting in November or December 2

General Prevention Measures

• Hand hygiene is the most important step in preventing nosocomial spread of RSV, with alcohol-based disinfectants preferred 2, 4
• Avoid tobacco smoke exposure, as it significantly increases severity and hospitalization risk 1, 2
• Promote breastfeeding, as breastfed infants have shorter hospital stays, less severe illness, and a 72% reduction in hospitalization risk for respiratory diseases 1, 2
• Limit visitor exposure during respiratory virus season to help prevent RSV transmission 1

Parent Education

• Symptoms of bronchiolitis (cough, congestion, wheezing) are expected to last 2-3 weeks, which is normal and does not indicate treatment failure 1

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Critical Pitfalls to Avoid

• Do not overlook feeding difficulties—aspiration risk increases significantly when respiratory rate exceeds 60-70 breaths/minute 1, 3
• Do not continue oral feeding based solely on oxygen saturation, as an infant may have adequate SpO2 but still have tachypnea >60-70 breaths/minute that makes feeding unsafe 1
• Do not use continuous pulse oximetry in stable infants, as serial clinical assessments are more important 1, 3
• Close monitoring is required during oxygen weaning in high-risk infants, such as those under 12 weeks of age or with hemodynamically significant heart or lung disease 1, 2