Ipratropium bromide causes bronchodilation by blocking muscarinic
cholinergic receptors. Adding anticholinergics to SABA is associated with
improved pulmonary function and, reduced hospitalization rates for those with
severe exacerbations, particularly using multiple-dose protocols. Many protocols
recommend its use for moderate severity as well.
Corticosteroids block formation of potent inflammatory mediators and reduce
airway inflammation. Systemic corticosteroids are associated with improved
pulmonary function and reduced hospitalizations. The effect on reducing
hospitalizations is time dependent, maximized with early administration. A
common metric regarding optimal asthma care is administration of systemic
corticosteroids within 60 minutes of arrival. Administration of systemic
corticosteroids is also associated with fewer ED relapse visits and hospitalization
at such return visits.
Systemic corticosteroid options include dexamethasone, prednisone,
prednisolone, or methylprednisolone. Dexamethasone has recently become more
popular with recent studies and systematic reviews reporting similar outcomes
and less vomiting compared to prednisone or prednisolone, though there was
heterogeneity among treatment regimens. Dexamethasone, prednisone, and
prednisolone have good oral bioavailability and tolerability, and oral route has
similar effectiveness compared to IV route. If patients are in severe distress or
actively vomiting, methylprednisolone or dexamethasone (IV or intramuscular)
should be considered. Other than these exceptions, oral corticosteroids are
preferred for milder exacerbations. For patients discharged from the ED, those
who received dexamethasone may not require additional doses considering its
longer duration of action compared to prednisone/prednisolone; those who
received prednisone/prednisolone are usually prescribed treatment for 3 to 5 days.
After initial therapy, it is important to reassess the need for continued and
adjunctive medications. Response to therapy can be categorized as good,
incomplete, or poor. Patients with good response have improvement with mild
features and can be observed briefly and subsequently discharged if not requiring
frequent SABA or having other indications for admission. Those with incomplete

or poor response continue to have moderate or severe features. They should
receive frequent, possibly continuous, albuterol, and adjunctive therapies such as
magnesium sulfate, heliox, or parenteral bronchodilator therapy should be
considered.
Many studies have evaluated use of medications considered adjunctive (e.g.,
continuous albuterol, magnesium sulfate, heliox) in comparison to initial standard
albuterol treatment, though, in practice, most clinicians administer them after


insufficient improvement with multiple albuterol and ipratropium treatments.
Adjunctive therapies such as magnesium sulfate and heliox can be administered
in conjunction with ongoing inhaled bronchodilators, and timing may vary
according to severity. Frequent reassessments during initial treatment for those
with severe exacerbations, anticipating the need for adjunctive therapy, are
essential to avoid delays.
Continuous nebulized albuterol treatment is recommended for patients with
severe exacerbations or poor response to initial inhaled bronchodilator treatment.
A systematic review found that continuous albuterol was associated with greater
improvement in peak expiratory flow rate (PEFR) and lower hospitalization rate,
particularly among those with moderate or severe exacerbations, with no increase
in adverse effects.
Magnesium sulfate causes bronchodilation by relaxing respiratory smooth
muscle. It is administered as a single IV bolus with a recommended dose of 50 to
75 mg/kg (maximum 2 g). Use of this therapy has been associated with improved
pulmonary function and reduced hospitalization rates. Magnesium can be
administered early in the course of patients with more severe exacerbations.
Others utilize magnesium after insufficient improvement from standard acute
therapy with multiple SABA and ipratropium doses, and such patients often
require hospitalization (frequently intensive care) although some patients may
improve enough to allow discharge. Ultimately, disposition following magnesium

administration is determined by the severity of the presentation and the response
to treatment.
Heliox is a mixture of helium and oxygen, thought to improve drug delivery in
obstructed airways due to its lower density and airflow resistance. The commonly
used mixtures (helium:oxygen) are 70:30 or 80:20, but use in patients with
significant hypoxemia may be limited. Contraindications for Heliox are
pneumothorax, pneumopericardium, or pneumoperitoneum; therefore a chest
radiograph (CXR) should be obtained prior to initiation.
Parenteral β-agonists are also options to consider for adjunctive therapy.
Epinephrine administered intramuscularly may be an option for severe
exacerbations, particularly as initial treatment for patients with significant airway
obstruction when delivery of inhaled medications to the lower airways may be
limited. Epinephrine autoinjectors used to treat anaphylaxis are readily available
in most EDs and can be used. Terbutaline may be administered subcutaneously or
intravenously as a bolus and continued as an IV infusion. Although commonly
included in many pediatric protocols for refractory asthma, pediatric studies
regarding use are limited.


Noninvasive ventilatory support (CPAP or BiPAP) may benefit patients tiring
from increased work of breathing and with impending respiratory failure.
Pediatric studies are limited but suggest that it is generally well tolerated. While
some studies suggest that it may reduce need for ICU admission, in practice, most
patients who require noninvasive ventilatory support are treated in an ICU setting.
CXRs are not routinely indicated for acute asthma exacerbations in children.
Wheezing is a common symptom of asthma and pneumonia in children, therefore
determining which patients warrant imaging can be challenging. Data regarding
children of all ages with wheezing and fever who had CXR for possible
pneumonia, suggest that approximately 5% will have radiographic findings of
pneumonia. However, the potential risks of CXR include radiation exposure and

false-positive results leading to unnecessary antibiotic therapy. In general,
patients with a typical asthma exacerbation do not routinely need imaging given
this low rate of abnormal findings. In a patient with mild to moderate respiratory
distress, the decision to perform a CXR may be deferred until reassessment after
initial treatment; focal abnormal breath sounds may have improved suggesting
atelectasis as opposed to pneumonia.
Clinical Indications for Discharge or Admission
In general, children requiring frequent albuterol (generally defined as more
frequent than every 2 to 4 hours) or having persistent hypoxemia require
admission. Other reasons for admission include significant dehydration, infection
requiring inpatient treatment or monitoring, or medical history that may impact
the respiratory system (e.g., cardiac disease, neuromuscular disorder, or metabolic
disorder). Most patients requiring frequent inhaled bronchodilator therapy or
adjunctive therapy (e.g., parenteral bronchodilators) will require hospitalization.
Protocols regarding which therapies require an ICU setting vary by institution.
Patients discharged should be encouraged to follow up with their primary care
providers (PCPs) within 1 to 3 days. Discharge instructions should include
information about care following the acute visit and may include formulation of
an asthma action plan. This provides an opportunity to assist patients with
management during future exacerbations and to encourage partnership with PCPs
for ongoing discussions and modifications of asthma care.
Inhaled steroids should be continued for patients currently taking them, and
clinicians should strongly consider prescribing them from the ED when indicated.
Patients with 2 or more days/nights of symptoms and/or albuterol use per week
likely have chronic asthma severity in the “persistent” range and inhaled steroids
are recommended. Data suggest that many patients treated for acute asthma in


EDs meet criteria for persistent chronic asthma severity, yet prescriptions are not
provided or patients are noncompliant with therapy. Therefore, the ED visit for

asthma represents an opportunity to improve outcomes for these children.

ASPIRATION PNEUMONIA
CLINICAL PEARLS AND PITFALLS
Aspiration pneumonitis refers to chemical injury and inflammation of
lung tissue after inhalation of foreign material, whereas aspiration
pneumonia refers to infection of lung tissue following pneumonitis.
Patients at risk for aspiration pneumonia include those with impaired
neurologic status, technology dependence, oropharyngeal dysfunction,
and gastrointestinal dysmotility.
Initial chest radiographs may be normal following aspiration episodes.
Treatment with antibiotics is generally reserved for patients with
significant respiratory impairment and signs of infection or complicating
medical history.
Treatment with corticosteroids is not routinely indicated.

Current Evidence
Aspiration of foreign material into the lung can result in inflammation and
impaired lung function. Aspiration pneumonitis (also referred to as chemical
pneumonitis) refers to chemical injury and inflammation of lung tissue from
inhaled foreign material, with sterile acidic gastric contents being the most
common source. Aspiration pneumonia refers to infection of lung tissue
following inhalation of foreign material, often due to bacteria from the
oropharynx.
The pathophysiology of pulmonary disease following aspiration has been
studied in animal models. These studies have demonstrated that a relatively large
volume acidic inoculum will induce pathologic changes within minutes including
atelectasis, peribronchial hemorrhage, and pulmonary edema. There is an
appreciable inflammatory response on pathology with polymorphonuclear cells
and fibrin along with hyaline membrane deposits. These responses are mediated

through multiple proinflammatory cytokines.
Aspiration of hydrocarbons is covered separately in Chapter 102 Toxicologic
Emergencies .