ED Pathway for Evaluation/Treatment of Children with Asthma

Asthma Assessment - Key Points

Variability Asthmatic children show acute airway obstruction differently depending on many factors including age and baseline lung function. One set of criteria cannot define asthma severity accurately across this wide spectrum of disease. Assignment of acute asthma severity is based on an overall integrated assessment of available signs, symptoms and (if able) lung function.
Spirometry/Peak Flow Pulmonary function tests are objective measures to directly assess airway obstruction. Valid measurement requires good effort by the patient and should be interpreted based on baseline lung function (when available) or a value predicted by height.
PASS Pediatric Asthma Severity Score (range 0-6, see below) includes key exam elements (wheezing, work of breathing, prolongation of expiration) that correlate with the overall assessment to follow trends over time.
Pulse Oximetry Assessment for hypoxemia is important, as it may not be apparent on physical examination. It most often reflects ventilation-perfusion mismatch due to mucus plugging or bronchospasm which may not correlate with asthma severity. This effect may be temporarily worsened by bronchodilator therapy. Decisions about oxygen therapy should be based on overall saturation trends. Continuous pulse oximetry should be withdrawn as patients improve.

Determine Severity Level of Asthma Exacerbation

  Mild Moderate Severe Respiratory Arrest
Wheezing None or mild (0)
None or end of
expiration only
Moderate (1)
Throughout expiration
Inspiratory/expiratory or absent due to poor air exchange
Diminished due to poor air exchange
Work of breathing None or mild (0)
Normal or minimal retractions
Moderate (1)
Intercostal retractions
Severe (2)
Suprasternal retractions, abdominal breathing
Tiring, inability to maintain work of breathing
Prolonged expiration None or mild (0)
Normal or minimally prolonged
Moderate (1) Severe (2) Severely prolonged
Breath Sounds /Aeration Normal Decreased at Bases Widespread Decrease Absent / Minimal
Breathlessness With activity or agitation While at rest
For infants:
  • Soft or shorter cry
  • Difficulty feeding
  • Prefers sitting
While at rest
For infants:
  • Stops feeding
  • Sits upright
Talks in Sentences Phrases Words  
Alert May be agitated Agitated Drowsy, confused
Pulse Oximetry > 94% variable variable variable
PEF (% of predicted by height) ≥ 70% 40-69% < 40%  

Guide to Breathing and Heart Rates in Awake Children

Age Normal Respiratory Rate
(per Minute)
Normal Heart Rate
(per Minute)
< 2 months < 60 < 160
2-12 months < 50 < 160
1-2 years < 40 < 120
2-5 years < 40 < 110
6-8 years < 30 < 110