Diagnosis
This test is the best in-clinic study to support a diagnosis of asthma.
Spirometry
Medication commonly used to assess obstruction reversibility
Short acting beta agonist
Using albuterol more than this many days per week suggests poor control.
More than 2 days per week
This medication is for rescue, not control.
SABA (albuterol)
Inability to speak full sentences and accessory muscle use = this severity.
Severe exacerbation
Asthma requires BOTH typical symptoms and this objective finding.
Evidence of variable airflow limitation/obstruction
This change after bronchodilator confirms reversibility.
FEV1 increase ≥12%
Number of nocturnal awakenings indicating poor control
First-line controller medication class.
Inhaled corticosteroids
First-line acute therapy.
Inhaled SABA
This spirometric ratio is used to identify obstruction.
FEV1/FVC
This parameter reflects airway obstruction
FEV1/FVC
This is the best objective tool to follow asthma control.
Spirometry
Check this before stepping up therapy
Technique/adherence
Should be added early in moderate–severe exacerbations.
Systemic corticosteroids
DAILY DOUBLE – Normal spirometry but high suspicion: this test can confirm asthma.
Bronchoprovocation testing (methacholine or exercise)
This value is used to diagnose obstructive airway disease in children.
FEV1/FVC ratio < LLN (80-85%)
Number of exacerbations requiring systemic steroids indicating poor control
>1 in last 12 months
Alternative or add-on controller class.
Leukotriene receptor antagonists
Life threatening sign/possible impending intubation
Silent chest/Minimal or absent air movement with breathing
What spirometry finding distinguishes Asthma from COPD?
Reversible obstruction
Methacholine or exercise challenge test positive result
>20% decrease in FEV1 from baseline
at least 3 months
Chronic daily use should be avoided due to toxicity.
Systemic (oral) steroids
Add on IV therapy to help with bronchodilation.
IV Magnesium sulfate