What are the clinical features and evidence‑based management of bronchiolitis in infants and young children, including indications for oxygen, hydration, bronchodilators, corticosteroids, ribavirin, antibiotics, and prophylaxis?

Management of Bronchiolitis in Infants and Young Children

Clinical Diagnosis

Bronchiolitis is a clinical diagnosis requiring no routine testing—diagnose based on history and physical examination alone. 1, 2

• Look for infants aged 1-24 months presenting with upper respiratory prodrome (rhinitis, cough) progressing to lower respiratory tract symptoms including tachypnea, wheezing, rales, nasal flaring, and use of accessory muscles 1
• Do NOT order chest radiographs, viral testing, or laboratory studies routinely—approximately 25% of hospitalized infants have radiographic findings often misinterpreted as bacterial infection 1, 3
• The pathophysiology involves viral infection (90% RSV) causing acute inflammation, edema, necrosis of small airway epithelial cells, and increased mucus production 1, 2

Supportive Care: The ONLY Evidence-Based Treatment

The cornerstone of management is supportive care alone—avoid all routine pharmacologic interventions. 2, 3

Oxygen Therapy

• Administer supplemental oxygen ONLY if SpO2 persistently falls below 90% 1, 2
• Maintain SpO2 at ≥90% using standard oxygen delivery 2, 3
• Healthy infants with SpO2 ≥90% at sea level on room air gain no benefit from supplemental oxygen, particularly without respiratory distress or feeding difficulties 3
• Discontinue oxygen when SpO2 ≥90%, infant feeds well, and has minimal respiratory distress 3

Hydration Management

• Continue oral feeding if the infant feeds well without respiratory compromise 2, 3
• Transition to IV or nasogastric fluids when respiratory rate exceeds 60-70 breaths/minute due to significantly increased aspiration risk 3
• Use isotonic fluids specifically—infants with bronchiolitis frequently develop SIADH, placing them at risk for hyponatremia with hypotonic fluids 3

Airway Clearance

• Use gentle nasal suctioning only as needed for symptomatic relief 2, 3
• Avoid deep suctioning—associated with longer hospital stays in infants 2-12 months of age 3
• Do NOT perform chest physiotherapy—no evidence of benefit 2, 3

What NOT to Do: Avoiding Ineffective Interventions

Bronchodilators

Do NOT use bronchodilators routinely—they lack evidence of benefit. 3, 4

• A carefully monitored trial may be considered, but continue ONLY if there is documented positive clinical response 3

Corticosteroids

Do NOT use corticosteroids routinely—meta-analyses show no significant benefit in length of stay or clinical scores. 3, 4

Antibiotics

Do NOT use antibiotics routinely—the risk of serious bacterial infection in infants with bronchiolitis is <1%. 3, 5

• Use antibacterial medications ONLY with specific indications of bacterial coinfection (acute otitis media, documented bacterial pneumonia) 3, 5
• Fever alone does NOT justify antibiotics 3, 5

Ribavirin

Do NOT use ribavirin routinely. 3, 6

• May be considered only in highly selected situations: documented RSV bronchiolitis with severe disease in high-risk patients (immunodeficiency, hemodynamically significant heart disease) 3
• Use is limited due to adverse side effects and risks to healthcare providers 6

Risk Stratification and High-Risk Populations

Infants <12 weeks, premature infants, and those with chronic conditions require particularly close monitoring. 2, 3

High-risk factors include: 3, 5

• Age <12 weeks (higher risk of apnea and severe disease)
• History of prematurity
• Hemodynamically significant congenital heart disease
• Chronic lung disease of prematurity
• Immunodeficiency

These infants may have abnormal baseline oxygenation and require closer monitoring during oxygen weaning 3

Prevention and Prophylaxis

Palivizumab (RSV Prophylaxis)

Administer palivizumab during the first year of life to specific high-risk infants. 1, 3

Indications include: 1, 3

• Infants born ≤28 weeks gestation during their first RSV season
• Infants born 29-32 weeks gestation up to 6 months of age
• Infants with chronic lung disease of prematurity (preterm <32 weeks requiring >21% oxygen for ≥28 days) requiring medical therapy within 6 months before RSV season
• Children ≤24 months with hemodynamically significant congenital heart disease

General Prevention Measures

• Promote exclusive breastfeeding—reduces hospitalization risk by 72% 2, 3
• Avoid tobacco smoke exposure—significantly increases severity and hospitalization risk 2, 3
• Limit visitor exposure during respiratory virus season 2, 3
• Promote hand hygiene 2, 3
• Restrict participation in group child care during RSV season for high-risk infants 3

Critical Clinical Pitfalls to Avoid

• Do NOT treat based solely on pulse oximetry readings without clinical correlation—transient desaturations occur in healthy infants 3, 5
• Do NOT use continuous pulse oximetry in stable infants—may lead to less careful clinical monitoring; serial clinical assessments are more important 3
• Do NOT overlook feeding difficulties—aspiration risk increases significantly when respiratory rate exceeds 60-70 breaths/minute 3, 5
• Do NOT continue oral feeding based solely on oxygen saturation—an infant may have adequate SpO2 but still have tachypnea >60-70 breaths/minute making feeding unsafe 3

Discharge Readiness Criteria

Discharge when: 2

• SpO2 ≥90% on room air
• Feeding well without respiratory compromise
• Minimal respiratory distress
• Reliable follow-up arranged
• Parents educated on warning signs

Expected Clinical Course

• Symptoms (cough, congestion, wheezing) typically last 2-3 weeks—this is normal and does NOT indicate treatment failure 2, 3
• Long-term sequelae include increased risk of recurrent wheezing as older children 2