Asthma Flashcards
Asthma is the most common chronic disease in …
childhood
Asthma
chronic inflammatory disorder of the airways
partially or completely reversible with bronchodilators
controllable but not curable
Symptoms
wheezing; usually only during asthma attacks/episodic
coughing
shortness of breath
tight chest
itchy or sore throat
rapid breathing
symptoms may be worse at night or wake the patient up
Prevalence
8-10% of population; 1 in 12; 25 million in U.S>
increasing
Inflammatory cells involved in the immunohistopathologic features of asthma
Neutrophils (especially in sudden-onset, fatal asthma exacerbations; occupational asthma, and patients who smoke)
Eosinophils
Lymphocytes
Mast cell activation
Epithelial cell injury
Risk Factors
Atopy - the body’s predisposition to develop an antibody called immunoglobin E (IgE) in response to exposure to environmental allergens; can be measured in blood; includes allergic rhinitis, asthma, hay fever, and eczema
Obesity
Triggers
environmental: dust mites, cockroach, animal dander, pollens
occupational: chemicals, fumes, smoke
cigarette smoke, upper respiratory infection, exercise, stress, post nasal drip, GERD (reflux)
Samter’s Triad
aspirin sensitivity
asthma
nasal polyps
Exam Findings
Vitals: May have elevated BP/ resp rate, decreased O2 sat
HEENT: allergic conjunctivitis, nasal swelling or polyps, throat erythema from PND (all atopy indicators)
LUNG: wheezing or prolonged expiratory phase; but normal if not having flare; wheezing may be absent during severe exacerbations; not moving enough air to even wheeze (‘silent chest’)
Chest inspection - using accessory muscles to breathe (rib/neck muscles show)
Heart: normal
Derm: cyanosis of lips or nails (if very bad)
What will the Arterial Blood Gas show in people with asthma?
respiratory alkalosis
What will tested sputum samples have in patients with asthma?
eosinophils or serum IGE level
Pulmonary Function Tests in Asthma Patients
typically done pre- and post-bronchodilator to look for reversibility of airflow obstruction
significant reversibility is defined by in increase of 12% or more and 200 mL in FEV1 or FVC after inhaling a short-acting bronchodilator
may be normal if not having an asthma attack
Bronchial Provocation Testing/Methacholine Challenge
done if asthma suspected but PFT not diagnostic.
A negative test has a negative predictive value for asthma of 95%
people whose airways do not narrow after inhaling methacholine are very unlikely to have asthma
Peak Expiratory Flow (PEF)
personal monitoring tool; used at home; gross estimate of GVC; self-measured and recorded; if patient isn’t trying, the results are not accurate – effort dependent
Fractional Exhaled Nitric Oxide (FeNO)
during inflammation, higher-than-normal levels of nitric oxide (NO) are released from epithelial cells of the bronchial wall; the concentration of NO in exhaled breath can help identify airway inflammation
usually used to determine if correct dose of anti-inflammatory is given
• Increased probability that symptoms are due to asthma if:
more than one type of symptoms (wheeze, shortness of breath, cough, chest tightness)
symptoms often worse at night or in the early morning
symptoms vary over time and in intensity
symptoms are triggered by viral infections, exercise, allergen exposure, changes in weather, laughter, irritants such as car exhaust fumes, smoke, or strong smells
Decreased probability that symptoms are due to asthma if:
isolated cough with no other respiratory symptoms
chronic production of sputum
shortness of breath associated with dizziness, light-headedness or peripheral tingling
chest pain
exercise-induced dyspnea with noisy inspiration (stridor)
Asthma severity and asthma control include two domains:
Current impairment: frequency and intensity of the patient’s symptoms and functional limitations (current or recent)
Risk: likelihood of untoward events (exacerbations, progressive loss of lung function, or medication side effects)
Quick Relief or Rescue Treatment
Bronchodilators/(short acting beta agonists) SABAs
(albuterol - Ventolin, Pro Air, Proventil; and others) inhaler or nebulizer
Used to relieve or prevent symptoms (prior to exercise) SABAS FOR ALL
Long-term Control Treatments
Corticosteroids: Inhaled: Many options, used frequently; Systemic: Oral prednisone, limit exposure
Long acting bronchodilators (LABA) - NEVER MONOTHERAPY, most often as combined inhaler
Step Treatment System
Step 1 (Intermittent) – SABA PRN
Step 2 (Persistent) – Low dose ICS
Step 3 – Low dose ICS + LABA OR Medium dose ICS; consider consultation
Step 4 – Medium dose + LABA; consult with asthma specialist
Step 5 – High dose ICS + LABA
Step 6 – High dose ICS + LABA + Oral Corticosteroid
Intermittent Asthma
symptoms: less than or equal to 2 days per week
night-time awakenings: less than or equal to 2 days a month
SABA use: less than or equal to 2 days a week
interference with normal activity: none
Lung Function:
FEV1: normal between exacerbations
FEV1 >80%
FEV1/FVC >85%
Mild Asthma
symptoms: more than 2 days per week
night-time awakenings: 3-4 days a month
SABA use: more than 2 days a week, but not daily
interference with normal activity: minor
Lung Function:
FEV1 >80%
FEV1/FVC >80%
Moderate
symptoms: daily
night-time awakenings: 1 time per week, but not nightly
SABA use: daily
interference with normal activity: some
Lung Function:
FEV1: 60-80%
FEV1/FVC : 75-80%
