Acute Bronchiolitis: Assessment and Management in the Emergency Department

Table of Contents

 

Differentiating bronchiolitis from asthma and reactive airway disease in young children can be challenging, and a rapidly changing clinical presentation can confound accurate assessment of the severity of the illness. This issue reviews risk factors for apnea and severe bronchiolitis; discusses treatments and therapies, and provides evidence-based recommendations for the management of pediatric patients with bronchiolitis. You will learn:

Which viruses cause the majority of cases of bronchiolitis

Signs and symptoms that can help differentiate bronchiolitis from other conditions that cause wheezing in young children

Risk factors for apnea and severe bronchiolitis

When diagnostic studies are warranted

Which patients require supplemental oxygen

Which treatments and therapies are most effective and generally recommended, and which are not recommended

The potential role for combination therapies and high-flow nasal cannula therapy in the management of bronchiolitis

1. Abstract
2. Case Presentations
3. Introduction
4. Critical Appraisal of the Literature
5. Pathophysiology
6. Etiology
7. Differential Diagnosis
   1. Asthma
8. Prehospital Care
9. Emergency Department Evaluation
   1. History
      1. Risk Factors for Severe Bronchiolitis
      2. Risk Factors for Apnea
   2. Physical Examination
      1. Respiratory Rate
      2. Oxygen Saturation
10. Diagnostic Studies
    1. Radiographic Imaging
    2. Viral Testing
11. Treatment
    1. Oxygen Supplementation
    2. Fluid Administration
    3. Nasal Suction
    4. Bronchodilators
       1. Albuterol/Salbutamol
       2. Epinephrine
    5. Corticosteroids
    6. Combination Treatment With Epinephrine and Corticosteroids
    7. Anticholinergic Agents
    8. Hypertonic Saline
    9. Summary of Recommendations
12. Controversies and Cutting Edge
    1. Bronchiolitis Treatments
       1. High-Flow Nasal Cannula
          • Predictive Factors of Unresponsiveness to High-Flow Nasal Cannula Therapy in the Emergency Department
       2. Nasal Continuous Positive Airway Pressure
       3. Comparison of High-Flow Nasal Cannula and Continuous Positive Airway Pressure
       4. Heliox
       5. Heliox and Nasal Continuous Positive Airway Pressure
       6. Leukotriene Receptor Antagonists
    2. Bronchiolitis and Vitamin D Deficiency
    3. Bronchiolitis and Asthma
13. Disposition
    1. Risk Factors for Unscheduled Emergency Department Return Visits
14. Summary
15. Time- and Cost-Effective Strategies
16. Risk Management Pitfalls in the Management of Pediatric Bronchiolitis
17. Case Conclusions
18. Clinical Pathway for Assessment and Management of Acute Bronchiolitis
19. Tables
    1. Table 1. Differential Diagnosis for Wheezing in Infancy
    2. Table 2. Risk Factors for Severe Bronchiolitis and Apnea
    3. Table 3. 2014 AAP Clinical Practice Guideline Recommendations for the Diagnosis and Management of Bronchiolitis
    4. Table 4. Key Management Recommendations in Bronchiolitis Guidelines
    5. Table 5. High-Flow Nasal Canncla Clinical Flow Ranges
    6. Table 6. Criteria for Hospitalization
20. References

Abstract

Acute bronchiolitis is the most common lower respiratory tract infection in young children that leads to emergency department visits and hospitalizations. Bronchiolitis is a clinical diagnosis, and diagnostic laboratory and radiographic tests play a limited role in most cases. While studies have demonstrated a lack of efficacy for bronchodilators and corticosteroids, more recent studies suggest a potential role for combination therapies and high-flow nasal cannula therapy. Frequent evaluation of patient clinical status including respiratory rate, work of breathing, oxygen saturation, and the ability to take oral fluids are important in determining safe disposition. This issue reviews the literature to provide evidence-based recommendations for effective evaluation and treatment of pediatric patients with acute bronchiolitis.

Case Presentations

As your shift is winding down at 4 am, a mother brings in her 9-month-old infant, whom she describes as “gasping for air.” The baby has had a runny nose and cough for a few days as well as a low-grade fever, but now he is breathing rapidly and wheezing, with lower intercostal retractions. The mother states that the infant has had wheezing in the past, and she asks if he might have asthma since “it runs in the family.” She also indicates that in the last 12 hours, he has not taken his usual amount of fluids. His oxygen saturation level is 87% on room air. You begin to think… should I treat this as reactive airway disease, asthma, or bronchiolitis? When should I give the patient albuterol, nebulized epinephrine, or oxygen? Does the infant need steroids? You also wonder whether this patient is going to tire and require assisted ventilation or whether there are any other alternatives to intubation.

It is the middle of influenza season, and the waiting room is full of coughing, sniffling children. Your patient, a 6-week-old boy, presents with rhinorrhea and poor feeding for the last 2 days. The mother states that he is not breastfeeding as well as usual due to his congestion. She says there is no family history of respiratory problems. The boy was born prematurely at 29 weeks' gestation, requiring admission to the NICU for 2 weeks for respiratory support. His oxygen saturation level is 91% to 92% on room air. Should you give supplemental oxygen? Should you send respiratory viral panels? Does the infant need to be admitted?

Introduction

Bronchiolitis is the most common lower respiratory tract infection (LRTI) in infants and young children aged < 2 years. Each year in the United States, LRTIs cause > 100,000 hospitalizations of children aged < 1 year. In particular, respiratory syncytial virus (RSV) is the leading cause of hospitalization in this age group. A study published in 2016 that summarized trends in bronchiolitis hospitalizations in the United States reported an average cost of $8530 per admission, or $1.7 billion nationwide.¹ Although there was a decrease in bronchiolitis hospitalizations between 2000 and 2009 (from 17.9 to 14.9 per thousand, respectively), bronchiolitis remains a major healthcare financial burden.^1,2

Despite the high prevalence of bronchiolitis, it is a clinical diagnosis without a common international definition. In 2014, the American Academy of Pediatrics (AAP) defined bronchiolitis as “rhinitis, tachypnea, wheezing, cough, crackles, use of accessory muscles, and/or nasal flaring in infants.”³ Children presenting with these symptoms are often given numerous diagnoses such as reactive airway disease, wheezing, cough, asthma, or pneumonia, as well as bronchiolitis.⁴ A study by Jartti et al suggested that the diagnosis of bronchiolitis should be restricted either to children aged < 24 months who are having their first episode of wheezing or to children aged < 12 months.⁵

This issue of Pediatric Emergency Medicine Practice uses evidence-based medicine to recommend strategies for effective evaluation and treatment of bronchiolitis in pediatric patients. Novel treatments for acute bronchiolitis such as nasal continuous positive airway pressure (nCPAP), high-flow nasal cannula (HFNC) therapy, nebulized hypertonic saline, and heliox also will be discussed.

Critical Appraisal of the Literature

A search of articles published on bronchiolitis from 1970 to 2019 was performed using Ovid MEDLINE^® and PubMed. Terms used in the search included wheezing, bronchiolitis, lower respiratory tract infection, RSV, infant respiratory distress, bronchiolitis guidelines, and steroids. More than 200 articles were analyzed, providing the background for further review. In addition, the Cochrane Database of Systematic Reviews was consulted. Major current international guidelines for the diagnosis and management of bronchiolitis were also reviewed and compared in relation to recommendations pertinent to the assessment and management of acute bronchiolitis in the emergency department (ED).^3,6-11

There is significant variation in the bronchiolitis literature in the definition of bronchiolitis, the clinical scoring systems, and outcome measures. Additionally, differing cutoff ages for bronchiolitis, as well as the lack of a valid clinical scoring system that correlates with clinically significant improvement and the inclusion of testing for RSV or other viruses in the diagnosis complicate a review and comparison of the literature. Although there are excellent published guidelines to help clinicians address this common condition, they often exclude the group at high risk for severe bronchiolitis (eg, patients who are at risk for serious complications, such as apnea, and who may need ventilatory support). The 2014 AAP clinical practice guidelines provide recommendations on the diagnosis, management, and prevention of bronchiolitis.

Risk Management Pitfalls in the Management of Pediatric Bronchiolitis

2. “I always admit first-time wheezing patients with bronchiolitis if they do not clear in the ED.”

One of the main reasons to admit patients with bronchiolitis is the concern regarding the development of apnea. Risk factors for apnea include young age (< 6-12 weeks old), prematurity, a history of apnea of prematurity, presentation with apnea, or apnea witnessed by a parent or healthcare provider. In addition, patients with bronchiolitis may be admitted because of respiratory distress, hypoxia, or dehydration related to the inability to take fluids secondary to increased work of breathing. Wheezing alone is not a criterion for admission unless it is associated with other risk factors for severe disease or apnea. Social factors such as parental comfort and reliability in ensuring appropriate care and follow-up should be taken into consideration when disposition decisions are made in the ED.

3. “The infant was wheezing, so we sent her home on steroids.”

In contrast to the demonstrated effectiveness of dexamethasone in treating asthma and croup, no conclusive evidence has been shown to date that the use of systemic dexamethasone improves outcomes in first-time wheezing patients with bronchiolitis. In addition, because of safety concerns with the use of high-dose inhaled corticosteroids in infants, these medications should be avoided unless there is a clear likelihood of benefit.

10. “The ‘happy wheezer’s’ pulse oximetry reading was 92% on room air, so I immediately admin-istered supplemental oxygen.”

In a wheezing patient who has no respiratory distress but has low SpO₂, the first priority is to ensure that pulse oximetry probes are placed appropriately, particularly in the active infant/child. Poorly placed probes and motion artifacts will lead to inaccurate measurements and false alarms. Before instituting oxygen therapy, the initial reading should be verified by repositioning the probe and repeating the measurement. The infant’s nose should also be suctioned. If the SpO₂ level remains ≤ 90%, oxygen should be administered. The infant’s clinical work of breathing should also be assessed and may be a factor in the decision to use oxygen supplementation.

Tables

References

Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.

To help the reader judge the strength of each reference, pertinent information about the study is included in bold type following the reference, where available. In addition, the most informative references cited in this paper, as determined by the author, are highlighted.

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79. Schuh S, Babl FE, Dalziel SR, et al. Practice variation in acute bronchiolitis: a Pediatric Emergency Research Networks study. Pediatrics. 2017;140(6):e20170842. (Retrospective cohort study; 3725 patients aged < 12 months)
80. Macias CG, Mansbach JM, Fisher ES, et al. Variability in inpatient management of children hospitalized with bronchiolitis. Acad Pediatr. 2015;15(1):69-76. (Prospective multicenter multiyear observational study; 2207 patients aged < 2 years)
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83. Hartling L, Wiebe N, Russell K, et al. Epinephrine for bronchiolitis. Cochrane Database Syst Rev. 2004(1):CD003123. (Systematic review; 14 studies)
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85. Christakis DA, Cowan CA, Garrison MM, et al. Variation in inpatient diagnostic testing and management of bronchiolitis. Pediatrics. 2005;115:878-884. (Systematic review; 17,397 patients aged < 12 months)
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87. Behrendt CE, Decker MD, Burch DJ, et al. International variation in the management of infants hospitalized with respiratory syncytial virus. Eur J Pediatr. 1998;157:215-220. (Retrospective review; 1563 patients aged < 12 months)
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