Coughing and sneezing children are not few and far between during the winter months. Sniffles, sneezes, and coughs hold a steady presence in the soundtrack of many parents’ lives. However, the common cold is not the only prevalent seasonal illness that can cause parents, children, and physicians grief this winter – bronchiolitis is another common condition and affects young children under the age of 2 years.
Bronchiolitis, sometimes described as a “bad cold”, is a viral inflammation of the bronchioles usually caused by the respiratory syncytial virus (RSV) (Bialy, Foisy, Smith, and Fernandes, 2011). TREKK (Translating Emergency Knowledge for Kids, trekk.ca) Bottom Line Recommendations for bronchiolitis describe the illness as being characterized by: acute inflammation of the airways, edema and necrosis of the epithelial cells lining small airways, bronchospasm, and increased mucus production. While most cases resolve in one or two weeks, around 20% of kids will have ‘postbronchiolitic syndrome’, otherwise known as more than four weeks of perhaps seemingly endless coughing and wheezing (Bialy, Foisy, Smith, and Fernandes, 2011). Infants most likely to experience a more severe bout of the disease are premature, younger, and have a low birth weight. Infants with chronic lung, heart, or neurological disease, immunodeficiency, and certain ethnicities will also be more at risk for a severe course of bronchiolitis.
Although bronchiolitis is the most common acute infection of the lower respiratory tract during the first year of life, with a wide variety of treatment interventions available and no ideal approach, physicians around the world are choosing different avenues for disease management. A Cochrane overview, including 11 reviews and nearly 8,556 participants, provides information about the most effective interventions for the treatment of bronchiolitis (defined as first episode of wheezing in children less than 2 years), those that do not seem to help, and those that may be harmful.
What is the evidence for different treatment options?
Using evidence from outpatient, inpatient, and ICU settings to contextualize varying levels of disease severity, the overview examined 11 treatment interventions for bronchiolitis in infants, including: antibiotics, bronchodilators, chest physiotherapy, epinephrine, extrathoracic pressure, glucocorticoids, heliox, hypertonic saline, immunoglobulin, inhaled corticosteroids, and oxygen therapy. Adverse events were also recorded. Here is the evidence:
Outpatient settings: Nebulized epinephrine decreased hospitalization rate by 33% on the first day of treatment. Combining glucocorticoid and epinephrine treatments decreased hospitalization rate within seven days by 35%. Small or moderate decreases in clinical severity were seen for both treatments (epinephrine and combined glucocorticoids and epinephrine) at 60 minutes and large decreases in severity at 120 minutes for epinephrine. Adverse events: The evidence showed no significant intervention specific adverse events for outpatients. However, the widespread use of epinephrine and particularly glucocorticoids are potentially dangerous – there is little known about the effect of these interventions in infants with comorbid illnesses.
Inpatient settings: 3% hypertonic saline versus 0.9% saline decreased length of stay by greater than one day, and improved clinical severity scores at one to three days. There was some weak evidence that chest physiotherapy modestly improved clinical severity at one to three days. Epinephrine, glucocorticoids, and bronchodilators did not significantly improve short term outcomes in comparison to placebo. Adverse events: When comparing oxygen delivery methods, inpatients using nasal prongs versus nasopharyngeal catheters experienced 81% less mucous related nasal blockage.
ICU settings: Immunoglobulin treatment decreased days spent in the ICU by nearly one day. Heliox versus air or oxygen inhalation did not significantly reduce length of stay in the ICU. Neither heliox nor extrathoracic pressure decreased need for invasive or non-invasive ventilation. Adverse events: ICU patients were almost two times more likely to have a drug-associated adverse event when given immunoglobulin than those taking a placebo.
Bringing evidence to the bedside
Evidence is hardly ever straight forward, making it difficult for healthcare professionals to translate research evidence to bedside care. Many factors complicate the interpretation of the evidence, particularly for bronchiolitis – including characteristics specific to the disease (e.g., varying definitions and severity) and the research studies (e.g., sample size, study quality, and variation in outcomes, measurement tools and time-points). Here is how the overview recommends bringing evidence to the bedsides of infants with bronchiolitis:
Outpatient settings: Nebulized epinephrine is the most effective treatment for outpatients with bronchiolitis. Patients need to be observed for two to three hours after treatment to track changes in symptoms. Immediate follow-up should be available to patients should deterioration in health occur. Glucocorticoids and bronchodilators are not recommended given insufficient evidence and possible adverse effects.
Inpatient settings: Nebulized hypertonic saline (3%) driven using oxygen should be given to those with respiratory distress associated with accumulated secretions in the upper and lower airways. The best time for this treatment is in the first three days. Although ideal dosages remain unclear, most studies administer the treatment 3-6 times daily. Chest therapy and inhaled glucocorticoids are not recommended. Nebulized epinephrine is generally not recommended, although it may be beneficial for reducing short term clinical severity, and could prove useful for a rapidly deteriorating infant.
ICU settings: Intravenous immunoglobulin, heliox, and extrathoracic pressure should not be used.
- American Academy of Pediatrics, Clinical Practice Guideline: The diagnosis, management and prevention of bronchiolitis, Pediatrics 134: e1474-e1502 (2014) http://pediatrics.aappublications.org/content/134/5/e1474.full.pdf+html
- Hartling L, Fernandes RM, Bialy L, Milne A, Johnson D, Plint A, Klassen TP, Vandermeer B. Steroids and bronchodilators for acute bronchiolitis in the first two years of life: Systematic review and meta-analysis. BMJ 342:d1714 (2011)
- Bialy L et al. The Cochrane Library and the Treatment of Bronchiolitis in Children: An Overview of Reviews. Evidence-Based Child Health 6: 258-275 (2011)