ASTHMA Flashcards
What is asthma?
Reversible, often intermittent, obstructive disease of the small airways.
Asthma
Restrictive or obstructive
Obstructive disease of the small airways.
Asthma
Upper or lower airway?
Lower airway disease.
Asthma
Large or small airways
Obstructive disease of the small airways.
Asthma
Reversible or irreversible?
Reversible, often intermittent, obstructive disease of the small airways.
Asthma
Constant or intermittent?
Reversible, often intermittent, obstructive disease of the small airways.
What are the 3 components to asthma?
• 3 components
- airway hyperreactivity
- bronchoconstriction
- inflammation
What is the process of inflammation in asthma?
Increased IgE binds to mast cells, initiating an inflammatory response, including increased Leukotrienes.
What age does asthma present?
• Can present at any age but initial occurrence most common in childhood.
Asthma
What does IgE bind to?
Mast cells
Asthma
What happens after IgE binds to Mast cells?
An inflammatory response is initiated.
Asthma
When an inflammatory response is initiated due to IgE binding with Mast cells, what else increases?
Leukotrienes
Asthma
Risk factors associated with asthma?
Atopy strongest risk factor family history air pollution obesity environmental tobacco smoke male gender
- Samter’s triad Asthma + chronic rhinosinusitis with nasal polyps + sensitivity to Aspirin and/or NSAlDs
- Atopic triad - Asthma, Atopic dermatitis (Eczema), & Allergic rhinitis
What is Atopy?
Atopy refers to the genetic tendency to develop allergic diseases such as allergic rhinitis, asthma and atopic dermatitis (eczema).
Atopy is typically associated with heightened immune responses to common allergens, especially inhaled allergens and food allergens.
What is Samter’s triad?
• Samter’s triad (Aspirin-exacerbated respiratory disease)
consists of
+ Asthma
+ Chronic rhinosinusitis with nasal polyps
+ Sensitivity to Aspirin and/or NSAlDs
What is the Atopic triad?
• Atopic triad (patients with one condition are likely to develop one or two of the other)
- Asthma
- Atopic dermatitis (Eczema)
- Allergic rhinitis
Asthma Triggers
3 types
- Intrinsic (non-allergic): anxiety, stress, exercise, cold air, dry air, hyperventilation, & viral infections.
- Extrinsic (allergic): animal dander, pollen, mold, dust mites, cockroaches etc. Associated with increased IgE.
- Other: medications (eg, Aspirin, NSAIDs, Beta blocker, histamine), GERD.
Asthma Triggers
Intrinsic
• Intrinsic (non-allergic):
anxiety, stress, exercise, cold air, dry air, hyperventilation, viral infections.
Asthma Triggers
Extrinsic
• Extrinsic (allergic):
animal dander, pollen, mold, dust mites, cockroaches etc.
Associated with increased IgE.
Asthma Triggers
Other
• Other:
medications
(eg, Aspirin, NSAIDs, Beta blocker, histamine),
GERD.
Clinical manifestations of Asthma
• Classic triad:
dyspnea,
wheezing and cough (especially at night).
May have chest tightness & fatigue.
What are some clues to severity of asthma?
previous intubations,
hospital admissions
ICU admission.
Asthma Physical exam findings
Prolonged expiration with wheezing,
hyper-resonance to percussion
decreased breath sounds
tachycardia
tachypnea
use of accessory muscles.
Asthma Physical exam findings
• Severe Asthma and Status asthmaticus:
inability to speak in full sentences
“tripod” positioning
silent chest (no air movement)
altered mental status (ominous)
pulsus paradoxes (inspiratory blood pressure drop > 10 mmHg),
PEFR < 40% predicted
• Findings of longstanding disease: Nasal polyps or Atopic dermatitis may be seen.
Asthma Physical exam findings
Findings of longstanding disease:
Nasal polyps
or
Atopic dermatitis may be seen.
DIAGNOSIS OF ASTHMA IN THE OFFICE
•Pulmonary function tests:
- gold standard in making the diagnosis of Asthma.
- Reversible obstruction (decreased FEV1, decreased FEV1/FVC; increased RV, TLC, and RV/TLC)
•Bronchoprovocation: Methacholine challenge (>20% decrease on FEV1) followed by bronchodilator challenge (increase of FEV1 Sl2 % is expected).
Asthma
•Pulmonary function tests:
- gold standard in making the diagnosis of Asthma.
- Reversible obstruction
decreased FEV1,
decreased FEV1/FVC;
increased RV, TLC, and RV/TLC
***In Office
Asthma
•Bronchoprovocation:
Methacholine challenge
(>20% decrease on FEV1)
followed by bronchodilator challenge
(increase of FEV1 Sl2 % is expected).
DIAGNOSIS OF AN ACUTE ASTHMA EXACERBATION
• Peak expiratory flow rate:
best & most objective way to assess exacerbation severity & patient response to treatment.
Asthma Discharge criteria
- Discharge criteria:
PEFR >70% predicted
or
PEFR > 15% initial attempt, subjective improvement.
• Pulse oximetry: Sa02 <90% indicative of respiratory distress
Asthma
ABG’s
• ABG:
not usually ordered in most exacerbations.
Respiratory alkalosis is expected (from tachypnea).
Pseudo normalization (normal C02) or respiratory acidosis may indicate impending respiratory failure.
Asthma
Chest X ray
• Chest radiograph: usually normal.
Generally, not helpful in the diagnosis of Asthma but may be used to rule out other causes of symptoms (eg, Pneumonia).
Asthma
Quick Relief for acute exacerbation (Rescue Drugs)
B2 agonists short acting SABA
- Albuterol, Levalbuterol, Terbutaline, Epinephrine
- Indications: first-line treatment for acute exacerbation - most effective & fastest (2-5 minutes).
- MOA: bronchodilator (especially peripherally), decreases bronchospasm, inhibits the release of bronchospastic mediators, increases ciliary movement, Decreases airway edema & resistance.
Asthma
Quick Relief for acute exacerbation (Rescue Drugs)
B2 agonists short acting SABA:
MOA
• MOA: bronchodilator (especially peripherally),
decreases bronchospasm
inhibits the release of bronchospastic mediators
increases ciliary movement
decreases airway edema & resistance.
Asthma
Quick Relief for acute exacerbation (Rescue Drugs)
B2 agonists short acting SABA:
Administration
• Administration:
MDI, nebulizer.
Nebulizers most common used in ED (MDI ±slightly more efficacious).
Generally given every 20 minutes x 3 doses (or continuous) + revaluation after 3 doses (at least q 1-2 hours).
Asthma
Quick Relief for acute exacerbation (Rescue Drugs)
B2 agonists short acting SABA:
Side effects
• S/E: B-1 cross reaction: tachycardia/arrhythmias, muscle tremors, CNS stimulation, hypokalemia.
Asthma
Quick Relief for acute exacerbation (Rescue Drugs)
Anticholinergics (antimuscarinics)
MOA
• MOA:
central bronchodilator (inhibits vagal-mediated bronchoconstriction) & inhibits nasal mucosal secretions.
positive synergy between p2 agonists & anticholinergics.
Most useful in the first hour.
Asthma
Quick Relief for acute exacerbation (Rescue Drugs)
Anticholinergics (antimuscarinics)
Anticholinergics (antimuscarinics)
Ipratropium
Asthma
Quick Relief for acute exacerbation (Rescue Drugs)
Anticholinergics (antimuscarinics)
Side Effects
• S/E:
thirst, blurred vision, dry mouth, urinary retention, dysphagia, acute glaucoma, BPH.
Asthma
Quick Relief for acute exacerbation (Rescue Drugs)
Corticosteroids
Corticosteroids
Prednisone , Methylprednisolone , Prednisolone
Asthma
Quick Relief for acute exacerbation (Rescue Drugs)
Corticosteroids
MOA
• MOA:
anti-inflammatory.
All but the mildest exacerbations should be discharged on a short course of oral corticosteroids (eg 3-5 days) unless contraindicated.
Steroids decrease relapse & reverse the late pathophysiology.
Short courses don’t need tapering (unless on chronic steroids, or recent treatment with repeated short courses in a short period).
Onset of action 4-8 hours for both oral & IV. *
Asthma
Quick Relief for acute exacerbation (Rescue Drugs)
Corticosteroids
Side Effects
• S/E:
immunosuppression, catabolic, hyperglycemia, fluid retention, osteoporosis, growth delays
Asthma
Long Term (Chronic, Control) Maintenance
Meds (ICS)
INHALED CORTICOSTEROIDS (ICS) Beclomethasone, Flunisolide, Triamcinolone
Asthma
Long Term (Chronic, Control) Maintenance
Indications
• Indications: first-line long term, persistent (chronic maintenance). Effective long-term control with very low incidence of systemic side effects. MOA: cytokine & inflammation inhibition.
Asthma
Long Term (Chronic, Control) Maintenance
Side effects
• S/E: oral candidiasis (using spacer & rinsing mouth after inhaler use decreases risk), dysphonia.
Asthma
Long Term (Chronic, Control) Maintenance
Meds (LABA)
LONG-ACTING P z AGONISTS (LABA)
Salmeterol, ICS/LABA: Budesonide/Formoterol, Fluticasone/Salmeterol
- Mechanism: bronchodilator that prevents symptoms (especially nocturnal asthma).
- Indications: long-acting p2 agonists added to steroids (or other long term asthma medications) ONLY if persistent asthma is not controlled with ICS alone (the option of increasing the ICS dose = addition of LABA). Once asthma control maintained (>3 months), step down off LABA is recommended.
Asthma
Long Term (Chronic, Control) Maintenance
LABA
MOA
• Mechanism: bronchodilator that prevents symptoms (especially nocturnal asthma).
Asthma
Long Term (Chronic, Control) Maintenance
LABA
Indications
• Indications:
long-acting p2 agonists added to steroids (or other long term asthma medications) ONLY if persistent asthma is not controlled with ICS alone (the option of increasing the ICS dose = addition of LABA).
Once asthma control maintained (>3 months), step down off LABA is recommended.
Asthma
Long Term (Chronic, Control) Maintenance
LABA
Contra-Indications
• CI
NOT used as a rescue drug in acute exacerbations or as monotherapy for long-term Asthma.
