CLASS 18 - Chronic Lower Respiratory Conditions - ASTHMA + COPD Flashcards
What is asthma?
Chronic inflammatory disorder of the airways
Causes airway hyper-responsniveness leading to wheezing, breathlessness, chest tightness, and cough
What are the 4 main triggers of asthma?
- infection
- allergens
- exercise
- irritants
Describe Respiratory Infections as triggers of asthma.
How can we prevent this?
Major precipitating factor of an asthma attack
- increases inflammation and hyperresponsiveness of the tracheo-bronchieal system
- can last 2-8 wks
- influenza vaccines recommended for children 6 mo and older and adults w asthma
Describe Nose + Sinus Problems as Triggers of asthma
Allergic rhinitis + nasal polyps.
Large polyps are removed.
Sinus problems are usually related to inflammation of the mucous membranes.
What is triad asthma?
Condition in which an individual has asthma, sinus inflammation with recurring nasal polyps, and sensitivity to aspirin and NSAIDs.
Describe Drugs and Food Additives as triggers of asthma. How can we treat this?
Typically occurs in people w triad asthma.
Wheezing develops in ~ 2 hrs
Occurs in people w sensitivity to salicylates (found in many foods, beverages, and flavourings).
Can be treated w beta-adrenergic blockers
Describe GERD (gastro-esophogeal reflux disease) as a trigger of asthma.
Exact mechanism is unknown, but reflux of acid could be aspirated into the lungs resulting in bronchoconstriction.
Describe air pollutants as triggers of asthma and provide examples.
Air pollutants can trigger asthma attacks.
- cigarette or wood smoke
- vehicle exhaust
- elevated ozone levels
- sulphur dioxide
- nitrogen dioxide
Describe Emotional Stress as a Trigger of Asthma
Psychological factors can worsen the disease process. Asthma attacks can trigger panic and anxiety.
Describe the process of the early-phase response of asthma. When does it occur? When does it subside?
Primarily bronchospasm.
increased mucus secretion, edema formation, increased amounts of tenacious sputum
peaks in 30-60 mins after trigger exposure
subsides in about 30-90 mins
Describe the process of the early phase response of asthma at the cellular level
Allergen enters body
B lymphocytes convert to plasma cells which release IgE antibodies.
IgE antibodies bind to mast cells which consume the allergen and present pieces of it on their surface.
Mast cell releases histamine and inflammatory mediators.
Results in bronchospasm, increased mucous secretion, edema, and increased amts of sputum
Describe the process of the late-phase response of asthma in terms of its severity, onset, duration, and treatment.
What will happen if airway inflammation is not treate or doesn’t resolve?
Can be more severe than the early-phase response.
Primarily inflammation
Peaks in 5-12 hrs, may last several hrs or days
Corticosteroids can prevent + reverse this cycle
If not treated or doesn’t resolve, may lead to irreversible lung damage.
Identify 3 factors that can result in airway obstruction.
Muscle spasm
Swollen mucosa
Mucus
What are the clinical manifestations of asthma?
When do they most often occur? How long do they last?
Unpredictable + variable
Recurrent episodes of wheezing, breathlessness, cough, and tight chest
Prolonged expiration
Particularly at night or in early morning
May be abrupt or gradual
Lasts minutes to hours.
Why might expiration be prolonged in cases of asthma? What would the inspiration:expiration ratio typically be in this case?
Ratio of 1:2, 1:3, or 1:4
Bronchospasm, edema, and mucus in bronchioles narrow the airways
Therefore air takes longer to move out.
Can wheezing be used as a method to gauge the severity of asthma?
No. Severe attacks may have no audible wheezing.
