Basics
Description
Lower respiratory tract infection by airway inflammation and bronchoconstriction with wheezes/tachypnea and respiratory distress and upper respiratory prodrome
Etiology
- Respiratory syncytial virus (RSV) in 85-90% of cases
- Influenza
- Parainfluenza
- Adenovirus
- Normally occurs during the winter months
Diagnosis
Signs and Symptoms
- Age <2 yr (usually 1 yr or younger)
- Nasal congestion, often with marked rhinorrhea
- Cough, sometimes associated with vomiting
- Wheezing
- Crackles, rhonchi
- Respiratory distress manifested by tachypnea, nasal flaring, retractions, grunting. Often progressive over a period of 1-3 days
- Fever usually <39.5 °C
- Hypoxemia may be present (usually mild). Cyanosis rare
- Decreased fluid intake common, frank dehydration uncommon
- Apnea may occur, particularly in young infants with history of prematurity
- Synagis, an RSV specific immunoglobulin, may be administered IM monthly during winter months in high-risk children. This reduces risk of RSV infection.
Essential Workup
- Clinical diagnosis
- Defining viral cause may be useful for cohorting in hospital if admitted.
- Assess ventilation clinically.
- Pulse oximetry:
- Confirms proper oxygenation on continuing basis
- Follows trends over the course of illness
Diagnosis Tests & Interpretation
Lab
- Most patients need no specific tests beyond oximetry.
- Nasopharyngeal aspirate/wash:
- Viral cultures
- Fluorescent antibodies
- Commercial kits are available.
- Consider when:
- Clinical symptoms suggestive of other cause (pertussis, chlamydia)
- Critically ill child
- Febrile child <3 mo old with bronchiolitis (consider UTI as coexistent cause of fever)
- Coexisting signs suggesting significant bacterial infection (positive aspirate does not exclude coexisting significant bacterial infection but such infections are uncommon)
- Bronchopulmonary dysplasia or chronic lung disease
- Coexistent cardiac disease
- Prematurity
- Other conditions warranting antiviral therapy (rare)
Imaging
CXR:
- Usually hyperinflation, airway disease, atelectasis, variable infiltrate:
- Atelectasis in young infants indicates more severe disease.
- Minority have airway + airspace disease; pneumonia usually viral
- Rarely changes management acutely
- Consider when:
- Need to exclude other diagnoses such as CHF, aspiration, congenital airway anomaly (rare)
- Chronic course with lack of resolution over 2-3 wk
- Critically ill infants with impending respiratory failure
- Atypical presentation in toxic or deteriorating child
- Not routinely indicated in typical clinical presentation
Diagnostic Procedures/Surgery
- Septic workup in febrile bronchiolitis <28 days of age if respiratory status permits
- In febrile infants 1-3 mo of age, consider catheterized urine culture
- Oximetry during significant distress
Differential Diagnosis
- Asthma/recurrent virus-induced wheezing: Severe bronchiolitis requiring hospitalization, and family history of atopy are risk factors for future asthma.
- Pertussis: No respiratory distress between coughing spasms, no wheezing
- Bacterial pneumonia: Often toxic appearance, no wheezing, isolated airspace disease (consolidation) with no airway abnormality on chest radiograph
- Foreign body: Sudden onset of symptoms, usually afebrile
- CHF: Pre-existing clinical red flags (failure to thrive [FTT], feeding problems)
Treatment
Pre-Hospital
- Young infants have limited respiratory reserve and decompensate rapidly with little warning.
- Monitor cardiorespiratory status and oxygenation.
- Supplemental oxygen if saturation <90-92% (sea level) and/or severe distress
- Watch for apneic pauses:
- Greatest risk of developing high-risk outcomes in children <7 wk, weight <4 kg, respiratory rate >80/min, heart rate >180/min, comorbidities, premature
- Bag-mask ventilation if recurrent apneas
Initial Stabilization/Therapy
- Pediatric advanced life support: Airway, ventilation, and fluid hydration
- Emergent intubation if recurrent apneas, impending respiratory failure
Ed Treatment/Procedures
- Supplemental oxygen if oxygen saturation <90-92% (sea level)
- Parenteral hydration if dehydration or severe respiratory distress. Many children may improve their intake once respiratory status has improved.
- Many children with bronchiolitis do not benefit from pharmacotherapy.
- Bronchodilators (albuterol, racemic epinephrine, l-epinephrine, levalbuterol):
- Should not routinely be used alone without determination of efficacy
- Some clinicians administer on trial basis with 2-3 consecutive treatments in those with moderate to severe distress and continue as part of management if there is a clear decrease in the work of breathing.
- Often utilized in significantly ill children
- Steroids:
- On their own do not change clinical course or hospitalizations in the majority of patients without prior atopic or family history.
- 2 doses of 1:1,000 l-epinephrine 30 min apart in the ED + 6 daily doses of oral dexamethasone may be useful in moderate to severe distress-reduces admissions by 35% by day 7, shortens time to discharge and duration of symptoms
- Conflicting evidence with another recent dexamethasone trial showing no benefit when used alone-synergy between steroids and epinephrine likely critical for efficacy
- Often used empirically in children with past or family history of atopy. Prednisolone common for this usage.
- Albuterol-dexamethasone combination efficacy not confirmed in a big trial.
- Bronchodilators alone after discharge not effective unless there was demonstrated effectiveness prior to discharge.
- Antibiotics:
- Not generally indicated since viral etiology
- Consider if associated signs of focal bacterial disease (otitis, focal pneumonia), radiographic evidence of isolated lobar consolidation without airway disease (usually bacterial pneumonia rather than bronchiolitis), significant toxicity, sepsis
- Ribavirin:
- No role in ED management and rarely used in the inpatient setting
Medication
- Albuterol: 2.5 mg/3 mL, 2-3 doses via nebulizer or 400 mcg via MDI/spacer 20-30 min apart in the ED. A therapeutic trial can be considered but continue only if there is a clear improvement in the work of breathing. Does not change overall disease outcomes.
- Levalbuterol: 1.25 mg/dose, 2-3 doses via nebulizer, 20-30 min apart in the ED (see above).
- l-epinephrine: 3 mL (1:1,000 solution), 2 doses via nebulizer 30 min apart in the ED or with
- Dexamethasone: 1 mg/kg/dose PO in the ED, then 0.15 mg/kg daily for 5 days
- Prednisolone (15 mg/5 mL): 1-2 mg/kg/d PO BID/3-5 d
- Comment 1: Most children require no medications. Bronchodilators alone rarely change outcomes. Initial trial of albuterol should be extended only if clear clinical improvement. Epinephrine-dexamethasone combination shown to decrease hospitalizations by day 7 of illness and may warrant consideration.
- Comment 2: Although no trial to date has identified any pharmacotherapeutic agent to change the course of the disease, a recent meta-analysis found that (a) inhaled epinephrine alone and epinephrine + oral dexamethasone appear to have half the odds of hospitalization compared to placebo and (b) salbutamol does not reduce hospitalizations in bronchiolitis.
Follow-Up
Disposition
Admission Criteria
- Need for supplemental oxygen (oxygen saturation on room air is <90-92% at sea level)
- Some institutions have developed protocols that allow full-term, stable children >6 months of age, who are well hydrated, have compliant parents, and good follow-up to be discharged on minimal oxygen after a prolonged period of observation in the ED.
- Inability to self-hydrate
- Marked increase work of breathing (tachypnea with retractions or accessory muscle use)
- Apnea
- Severe underlying chronic lung disease or cardiac disease
- Persistent marked respiratory distress 4 hr after a trial of epinephrine and dexamethasone
- Significant comorbidity/suspicion of alternative diagnosis/underlying systemic disease/immunodeficiency or immunosuppressive therapy
- Strongly consider in infants <7 wk, weight <4 kg, respiratory rate >80/min, heart rate >180/min, comorbidities, or prematurity
- Caretaker noncompliant or unable to monitor child closely
Discharge Criteria
- Feeding reasonably well
- Acceptable room air saturation (see above)
- Absence of significant respiratory distress
- Follow-up available within 24 hr
- Compliant home environment
- Discharge instructions:
- Symptoms may persist for 2-3 wk
- Frequent small feeds
- Bronchodilators after discharge not uniformly beneficial
Followup Recommendations
Because of the progressive nature of bronchiolitis close follow-up is required, particularly early in the illness alerting parents to the likelihood of worsening respiratory distress, dehydration, and apnea.
Pearls and Pitfalls
Infants with bronchiolitis often present with respiratory distress associated with hypoxia, dehydration, and/or apnea. Aggressive monitoring may be warranted.
Additional Reading
- American Academy of Pediatrics Subcommittee on Diagnosis and Management of Bronchiolitis. Diagnosis and management of bronchiolitis. Pediatrics. 2006;118:1774-1793.
- Corneli HM, Zorc JJ, Mahajan P, et al. A multicenter, randomized, controlled trial of dexamethasone for bronchiolitis. N Engl J Med. 2007;357:331-339. [Erratum, N Engl J Med. 2008;359:1972.]
- Hartling L, Bialy LM, Vandermeer B, et al. Epinephrine for bronchiolitis. Cochrane Database Syst Rev. 2011;15(6):CD003123.
- Hartling L, Fernandes RM, Bialy L, et al. Steroids and bronchodilators for acute bronchiolitis in the first two years of life: Systematic review and meta-analysis. BMJ. 2011;342:d1714.
- Kellner JD, Ohlsson A, Gadomski AM, et al. Bronchodilators for bronchiolitis. Cochrane Database Syst Rev. 2000;(2):CD001266.
- Levine DA, Platt SL, Dayan PS, et al. Risk of serious bacterial infection in young febrile infants with respiratory syncytial virus infections. Pediatrics. 2004;113:1728-1734.
- Plint AC, Johnson DW, Patel H, et al. Epinephrine and dexamethasone in children with bronchiolitis. N Engl J Med. 2009;360:2079-2089.
- Ralston S, Hill V, Waters A. Occult serious bacterial infection in infants younger than 60 to days with bronchiolitis: A systemic review. Arch Pediatr Adolesc Med. 2011;165:951-956.
- Schuh S, Coates AL, Binnie R, et al. Efficacy of oral dexamethasone in outpatients with acute bronchiolitis. J Pediatr. 2002;140:27-32.
- Schuh S, Lalani A, Allen U, et al. Evaluation of the utility of radiography in acute bronchiolitis. J Pediatr. 2007;150:429-433.
See Also (Topic, Algorithm, Electronic Media Element)
Asthma, Pediatric
Codes
ICD9
- 466.1 Acute bronchiolitis
- 466.11 Acute bronchiolitis due to respiratory syncytial virus (RSV)
- 466.19 Acute bronchiolitis due to other infectious organisms
ICD10
- J21.0 Acute bronchiolitis due to respiratory syncytial virus
- J21.1 Acute bronchiolitis due to human metapneumovirus
- J21.9 Acute bronchiolitis, unspecified
- J21 Acute bronchiolitis
SNOMED
- 4120002 Bronchiolitis (disorder)
- 57089007 respiratory syncytial virus bronchiolitis (disorder)
- 13089009 adenoviral bronchiolitis (disorder)
- 5505005 Acute bronchiolitis