Bronchiolitis

Bronchiolitis is an acute respiratory illness caused by several viruses, most commonly respiratory syncytial virus. Other pathogens implicated include parainfluenza viruses, rhinoviruses, influenza viruses, and metapneumoviruses. These viral infections inflame the smaller airways, causing increased mucous secretion, cell sloughing, submucosal edema, small airway narrowing and obstruction. Hypoxia is due to an obstructive shunt, causing ventilation/perfusion mismatch. Obstruction leads to end expiratory air trapping and decreased lung compliance, resulting in an increased work of breathing.

Quick Summary

Interventions

Nasal suctionin
Indicated for the child in mild respiratory discomfort from bronchiolitis
Afrin Nasal Spray
Indicated for the child in mild respiratory discomfort from bronchiolitis
Warm/Humidified Oxygen
Indicated for the child in mild respiratory discomfort from bronchiolitis
Albuterol
Improve transient clinical scores and patient comfort but do not affect disease resolution, length of stay, or hospital admissions. May be useful in distinguishing asthma from bronchiolitis
Racemic Epinephrine
Improve transient clinical scores and patient comfort but do not affect disease resolution, length of stay, or hospital admissions
Hypertonic Saline
Some incremental benefit in clinical scores after 24 hours, but has not been shown to improve patients in a 12 hour ED stay or decrease hospital admissions
Corticosteroids
Corticosteroid use alone has been proven in large center trials to not be effective at decreasing hospital length of stay or admissions. However, more evidence is needed to determine if corticosteroids + racemic epinephrine provides a synergistic effect in the treatment

EMRAP Bronchiolitis flow sheet

Useful Reading

Who Is At Risk?

Bronchiolitis is a clinical diagnosis in children under 2 years of age.
Severe bronchiolitis may be found in children who are premature

What Will it Look Like?

Most typically shows up in the winter months as a viral respiratory syndrome prodrome, followed by increased respiratory effort, rhinorrhea, coryza, wheezing, and rales manifesting as grunting, intercostal, subcostal retractions with nasal flaring. In children with severe disease, respiratory distress, respiratory fatigue, cyanosis, mottling, and hypoxia may present. Bronchiolitis symptoms peak in day 3-5 of illness, but the course of the illness may last up to 4 weeks.

Alternate Diagnoses

  • Asthma – Usually children with bronchiolitis are differentiated via a temporal correlation with wintertime, a prodrome of viral illness, and a lack of family history of ectopy. Asthma, diagnosed at later ages of life, is diagnosed by meeting the Modified Asthma Predictive Index (mAPI) clinical score as shown below.
  • GERD – A history of wheezing associated with feeding, coughing, or vomiting.
  • Pneumonia – an acute febrile illness with cough, coryza, tachypnea, wheezing, focal physical exam findings of lung consolidation.

What do I order?

According to the AAP clinical practice guidelines on bronchiolitis, most studies are noncontributory. A Chest X-ray should be ordered when the physical exam finds focal lung findings concerning for infiltrative disease, concern for a foreign body, suspected airway compromise, or when respiratory distress is severe enough to prompt an ICU admission. Chest radiographs apart from these exceptions have not been shown to correlate with severity of bronchiolitis and may lead to inappropriate use of antibiotics. RSV nasal swabs and viral panels in an otherwise healthy child are not useful. These studies may be useful as an inpatient, but do not affect overall emergency department management of the clinical disease. An otherwise healthy child with a positive RSV result is very unlikely to have a serious bacterial infection (SBI). However, children who are premature, ventilated, recently discharged, or otherwise immunocompromised should be tested to guide therapy. Routine lab work is likely unhelpful as well.

What do I do?

  • Nasal suctioning, Oxymetazoline (properly dosed to avoid CNS depression and hypopnea and/or apnea) or phenylephrine nasal spray and supplemental humidified, warm oxygen are all indicated for the child in mild respiratory discomfort from bronchiolitis.
  • Albuterol, racemic epinephrine improve transient clinical scores and patient comfort but do not affect disease resolution, length of stay, or hospital admissions.
  • Hypertonic saline has some incremental benefit in clinical scores after 24 hours, but has not been shown to improve patients in a 12 hour ED stay or decrease hospital admissions.
  • Oxygen therapy and following pulse oximetry to gauge respiratory status for patients with bronchiolitis is not recommended, but evidence to support these recommendations is weak.
  • Corticosteroid use alone has not been proven in large center trials to be effective at decreasing hospital length of stay or admissions. However, more evidence is needed to determine if corticosteroids + racemic epinephrine provide a synergistic effect in the treatment.
  • In a child with respiratory distress and poor ventilation/oxygenation, treatment with bronchodilators, epinephrine, hypertonic saline, and supplemental oxygen may be imperative for symptom control and stabilization.

Who should I admit?

Children at risk for apnea (Small for gestational age, less than 2months, O2 sat <90, previous hx apnea). In children less than 6 weeks of age, the risk of apnea approaches 5%.
The Canadian Pediatric Society Guidelines (2014) recommends the following criteria for admission:

  • Signs of severe respiratory distress (indrawing, grunting, RR>70)
  • Supplemental O2 required to keep saturations >90% (note that our experts accept an O2 sat of as low as 91% for discharge in a child that otherwise looks well)
  • Dehydration or history of poor fluid intake
  • Cyanosis or history of apnea
  • Infant at high risk for severe disease (premature
  • Family unable to cope

Credit

Credit to Dr. Lawrence Lau for compiling and summarizing this information

References

  • Clinical practice guideline: The diagnosis, management and prevention of bronchiolitis. 2014. Pediatrics. 2014;134:e1474–e1502
  • Joseph, Madeline. Evidence Based Assessment and Management of Acute Bronchiolitis in the Emergency Department. Pediatric Emergency Medicine Practice. March 2011 Vol. 8:3 EBMedicine.net
  • Helman, Anton. Emergency Medicine Cases: Episode 59 Bronchiolitis
  • Orman, Rob. EMRAP: Episode 154: Notes from the Community – Bronchiolitis: Part 1. Emergency Medicine Reviews and Perspectives. July 2015 Vol 14:7
  • Orman, Rob. EMRAP: Episode 155: Notes from the Community – Bronchiolitis: Part 2. Emergency Medicine Reviews and Perspectives. August 2014 Vol 14:8