Title: ASTHMA
1ASTHMA
2Definition
- Chronic inflammatory disorder of the respiratory
airways which includes 3 components - bronchial hyperresponsiveness to a variety of
stimuli (i.e. allergens, respiratory viruses,
environmental exposures and others) - reversible airflow obstruction
- associated with recurrent episodes of respiratory
symptoms (i.e. most commonly wheezing, SOB, chest
tightness and cough)
3Pathophysiology
- Asthma has 2 mechanisms of reaction
- Allergen induced bronchoconstriction
- IgE mediated response? mast cell stimulation?
mediators released - Other stimuli induced bronchoconstriction
- Inflammatory mediated response? inflam cell
stimulation? neuro/hormonal reflexes in the lungs - Both cause edematous swelling of airway walls?
hyperresponsiveness and ultimately ? airflow
obstruction, which can occur in minutes, hours,
days or weeks
4Epidemiology 2000
- Prevalence is increasing
- 17 million patients with asthma in the US
- Age
- gt18 yrs 11 million (62)
- 2-17 yrs 6 million (38)
- Race
- 8.9 million Caucasian (52)
- 3.5 million Latino (21)
- 3.3 million African American (19)
- 1.3 million other (8)
- Gender Male 42, Female 58
5Morbidity and Mortality
- Most often associated with failure to appreciate
severity of exacerbation by pt and/or provider - Deaths gt 5,000/year but decreasing overall since
1990, probably due to better management from PCP - Hospitalizations 466,000 in 2000
- 5 required ICU
- ED Visits
- 1.9 million in 2000
- females 2X gt than males
- the 11th most common diagnosis
- 20-30 of these required hospitalization
6Morbidity and Mortality Contd
- Costs gt 6 billion/year
- average annual cost/pt with attack 600 compared
with 170 with no attack - cost includes the 3 million lost workdays in the
US per year - Important Note Most ED visits, and therefore,
hospitalizations are preventable. A useful
practice is to assume that every exacerbation is
potentially fatal.
7Risk factors for death from Asthma
- Past history of sudden, severe exacerbations
- Prior intubation
- Prior admission to ICU
- More than 2 hospitalizations in past year
- More than 3 ED visits in the past year
- Recent use/withdrawal from systemic steroids
- Comorbid conditions
- Difficulty perceiving severity of disease (more
common in males)
8Asthma Attack Evolution
- Two different pathogenic scenarios involved
- Airway inflammation predominant
- pts show a progressive deterioration over 6
hours, days or weeks (slow onset attack). - The prevalence is 80-90 in adults and usually
assoc with infectious causes. - Have a slower therapeutic response
- Bronchospasm predominant
- Pts present with a sudden onset attack over
minutes to 3-6 hrs (asphyxic or hyperacute
attack). - Usually associated with allergens, exercise and
stress. - Have a more rapid and complete response
9Diagnosis
- Usually cannot be done in the first visit
- History and Physical exam
- Classic triad
- Cough, SOB and wheeze
- Not all that wheezes is asthma and not all asthma
wheezes. - Presence of wheezing is a poor predictor of
airflow obstruction, therefore need to use other
findings - Vital signs, RR, mentation, accessory muscle use
10Diagnosis Contd
- Pulmonary Funtion Testing
- Peak Expiratory Flow Rate (PEFR)
- Measured by age and height
- Spirometry with bronchodilator evaluation
- FEV1, FVC and FEV1/FVC ratio
- gt 80 predicted borderline obstruction
- 60-80 mild obstruction
- 40-60 moderate obstruction
- lt40 severe obstruction
- Serial testing over time
- Bronchoprovocation testing with methacholine
- Same deal as with exercixe stress testing in
angina
11Diagnosis Contd
- CXR
- Only on initial evaluation
- Can see flattened diaghrams from hyperinflation
- Blood tests
- none
- Allergy testing
- Allergy skin test
- Blood radioallergosorbent test (RAST)
12Classification of Asthma
Stage Daytime symptoms Nighttime Symptoms PEFR of predicted FEV1 of predicted
Mild Intermittent Asthma lt 2x/wk lt 2 nights/wk gt80 lt20
Mild Persistent Asthma gt 2x/wk, but lt1x/day gt 2 nights/mo gt80, but fluctuates gt20 20-30
Moderate Persistent Asthma Daily Sx gt 1 night/wk 60 - 80 gt30
Severe Persistent Asthma Continual Frequent 4-7x/wk lt 60 gt30
13Overall Management
- 4 key component to success
- Patient Monitoring
- Controlling Triggers
- Pharmacotherapy
- Patient Education
14Overall Management contd
- Monitoring
- Peak Expiratory Flow Rate (PEFR) can be used to
follow impact of change in therapy upon lung fxn
and/or to assess severity of attack, NOT to
detect presence of airflow obstruction - Measurement is highly dependent on users
technique - Measure with patient standing and should be a
evening trial - Record best of 3 tries
- Pts should have device at home, however, to
establish a baseline - Encouraged to be used at least by pts with
mod-severe disease - Mixed data on whether or not home monitoring is
beneficial - For the future
- Sputum Eosinophilia as a marker for treatment
- Exhaled nitric oxide as a way to predict airway
inflammation and asthmatic control
15Overall Management Contd
- Controlling Trigger Factors
- Identify and avoid triggers
- They vary from person to person and time to time
(for females most commonly have exacerbations in
premenstrual phase) - Generally fall into 6 categories
- 1. Allergens (pollen), 2. Irritants (air
pollutants), 3. Respiratory infections (viruses),
4. Physical activity, 5. Chemicals (foods and
drugs) and 6. Emotional stress. These are the
main ones identified clinically - Allergic rhinitis, chronic sinusitis, polyposis,
GERD, menses, and pregnancy are others that may
also contribute to exacerbations - Once identified a.) avoid the trigger, b.) limit
exposure if cannot be completely avoided, c.)
take an extra dose of bronchodilator before
exposure, but careful with exceeding normal
amounts
16Overall Management Contd
- Pharmacologic Therapy
- This is the mainstay of management in most
patients with asthma, and varies with type and
severity of asthma. - Relievers vs. Controllers
- Fast acting Slow acting
- Relieve bronchospasm Controls inflammation
- Stops symptoms Prevents symptoms
- Take PRN Take everyday
17Overall Management Contd
- Mild Intermittent Asthma (refer to prior slide)
- Includes exercise induced asthma
- Short Acting Inhaled beta-agonists Albuterol
(Proventil, Ventolin) - Rapid onset of action, get maximal potency of
bronchodilation and minimal side effects. - Encourage to use 10 minutes prior to exposure to
a trigger - Meter dose inhalers (MDIs) are now using
ozone-safe propellants instead of
chlorofluorocarbon (CFC) - Alternate delivery forms have been developed
- Albuterol now comes in powder form
- Ipratropium (Atrovent) is NOT a good reliever for
asthma - Mast Cell Stabilizers (Cromolyn, Nedocromil)
- Have no benefit to relieve immediately asthmatic
symptoms - Limited role in adults
18Overall Management Contd
- Mild Persistent Asthma
- All Persistent asthmatics need a controller
- The assumption behind this recommendation is that
regular medication use will reduce the frequency
of symptoms, improve overall quality of life and
decrease the risk of serious attacks and
therefore lower the rate of ED visits and
hospitalizations - Inhaled Steroids
- The gold standard against which all other
controlling therapy is compared - Decreases mast cell and airway inflammation
- Side effects include
- Local effects (thrush, dysphonia, and bad taste)
- Systemic effects (cataracts, bone loss, increase
IOP, growth suppression) are dose related, rare
and occur particularly in prolonged, high dose
users - Using a spacer device is recommended in order to
maximize medication delivery to the lung and
minimize oral deposition - No advantage to using albuterol immediately prior
to inhaled steroid to achieve more lung
deposition - Using an inhaled steroid with a systemic oral
steroid is not contraindicated, but should be
limited
19Not All Steroids Are Created Equal
Drug Low dose Medium dose High dose
Beclomethasone MDI (Vanceril) 40 mcg 2-6 pfs/day 16-12 pfs/day gt12 pfs/day
Budesonide DPI (Pulmacort) 200mcg 1-3 pfs/day 3-6 pfs/day gt6 pfs/day
Flunisolide MDI (Aerobid) 250 mcg 2-4 pfs/day 4-8 pfs/day gt8 pfs/day
Fluticasone DPI (Flovent) 50mcg 2-6 pfs/day 100 mcg 6-12 pfs/day 250 mcg gt12 pfs/day
Triamcinolone MDI (Azmacort) 100 mcg 4-10 pfs/day 10-20 pfs/day gt20 pfs/day
20Overall Management Contd
- Moderate Persistent Asthma
- Incorporates the mild asthmatic receiving
treatment, yet remain symptomatic - Try to find the combination that works
- Long Acting Beta Agonists
- Formoterol (Foradil) and Salmeterol (Serevent)
- Both have similar characteristics, but Foradil
has a faster onset of action (5 min vs 20 min) - Inhaled meds that have long half lives which
allow bid dosing. No longer in MDI, now in DPI - Found to be less efficacious than inhaled
steroids in improvement in lung fxn, control of
Sx and amt of attacks - Currently 2nd line after inhaled steroids, and
not recom as monotherapy for mild asthma - Combo therapy (Advair) with inhaled steroid has
shown more benefit in mod-severe persistent
asthma.
21Overall Management Contd
- Leukotriene Receptor Antagonists (LTRAs)
- Zafirlukast (Accolate) bid dosing
- Montelukast (Singulair) qday dosing and
therefore is the favored one - also approved for allergic rhinitis.
- tolerated well because of low side effect profile
- Approved down to age 2
- Currently positioned 3rd line, after inhaled
steroids and long acting beta agonists. - Have a varied response among individuals with
asthma - May be used as first line in very mild stage 2
asthma - May discontinue after 2-3 weeks in
non-responders
22Overall Management Contd
- High-dose inhaled steroid
- Fluticasone 100 -250 mcg
- Budesonide 200 mcg
- As the dose of inhaled steroid increases, the
likelihood of systemic absorption and potential
for significant side effects from long term use
also increases. - Therefore, every effort should be made to reduce
the dose of inhaled steroid, seeking to find the
lowest dose that continues to maintain good
control and minimize the risk of exacerbations - Systemic effects are far less frequent than with
systemic oral steroids - Long-acting beta agonists
- LTRA
23Overall Management Contd
- Severe Persistent Asthma
- Patients who fail to achieve symptom control
despite 2-3 controller medications - Long-acting oral bronchodilator (theophylline)
- Used for its intrinsic anti-inflammatory effect,
bronchodilation is considered secondary - Increases ciliary motility, mucus clearance and
diaphragmatic motility - Not tolerated well because of Sfx nausea,
cramps, diarrhea, and insomnia - Narrow therapeutic index requiring check of serum
levels - Toxicity can result in seizures and death
- 24 hour preparations are preferred (Uniphyl)
- Currently 4th line, after inhaled steroids,
long-acting beta agonists, and LTRA. - Oral steroids
- Want to avoid as much as possible. If going to
use, then use in short spurts or tapering regimens
24Overall Management Contd
- Choosing a treatment strategy
Start aggressively then step down once controlled Start with a single agent and step up until control is achieved
Controls symptoms quickly May take several months to achieve control
More side effects Less side effects
Recommended by NIH guidelines for asthma, expert panel report 2 Requires patience and very close follow-up
25Overall Management Contd
- Adjunctive Medications
- Treating comorbid conditions improves asthma
- Antihistamines
- Treating allergic rhinitis decreases
responsiveness to triggers - Nasal steroids
- Have been shown to improve symptoms in patients
with both AR and asthma - Some studies indicate benefit in asthma alone
- H2 blockers and/or PPIs
- Prevalence of GERD in asthmatics ranges from
34-80 in various studies - Improving reflux has been shown to improve control
26Overall Management Contd
- Patient Education
- Medication Myths
- Nebulizers offer improved medication delivery and
are referable for more severe asthmatics - MDIs used through a spacer can offer more
efficient medication delivery at a fraction of
the cost and time when compared to a nebulizer - Inhaled steroids increase birth defects or are
risky in pregnancy - Recent studies have shown no increase in birth
defects or decrease in birth weight with the use
of any inhaled steroid - Category B or C, except Azmacort D
27Overall Management Contd
- Asthma flow sheet (blue)
- Found on left side of chart, along with diabetic
flow sheet - Convenient tracking of symptoms, peak flows
- There is a cheat sheet on bottom of page for
staging - Can write on progress note see blue asthma flow
sheet
28Overall Management Contd
- The Asthma Action Plan
- Helps patients and families understand complex
regimen - The Green Zone (PEFR gt 80 predicted)
- What to do on normal days
- The Yellow Zone (PEFR 50-80 predicted)
- Caution
- The Red Zone (PEFR lt 50)
- Danger
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