Asthma Flashcards
Reading assignment: Principles of Pulm Med Chapter 5 Hashim, T., AH Chaudry, K Ahmad, et al. Pneumomediastinum from a Severe Asthma Attack. JAAPA 2013; 26 (7): 29-331. 1.Discuss the epidemiology of asthma, including the contributions of genetic predisposition and environmental factors. 2. Discuss the pathophysiology of asthma and the role of inflammatory mechanisms of asthma. 3. List risk factors for asthma exacerbations. 4. When given a clinical scenario, develop and defend a differentia
What is SABA?
Short Acting Beta Agonist
Example of SABA?
Albuterol
What is LABA?
Long Acting Beta Agonist
Examples of LABA?
Salmeterol
Formoterol
What is LTRA?
Leukotriene Receptor Antagonist
Example of LTRA?
Singulair
Montelukast
About how much of the US is affected by Asthma?
8%
~22 million people (Men and Women
Annual treatment costs of asthma in adults?
18 billion dollars
Total costs – Doubled (missing school/work)
What is the hygiene hypothesis?
Factors that have been implicated include urbanization, air pollution, passive smoking, and change in exposure to environmental allergens.
Children aren’t exposed to anything to build their immune system anymore
What are some components of the pathophysiology of asthma?
- Airway inflammation
- Intermittent airflow obstruction
- Bronchial Hyperresponsiveness
Recent research shows that asthma is…
NOT a single disease! Different phenotypes
Asthmatic Bronchioles are more ______ than normal bronchioles
Constricted
Some of the principal cells identified in airway inflammation include:
Mast cells Eosinophils Epithelial cells Macrophages Activated T lymphocytes
What can cause airway obstruction?
- Acute Bronchoconstriction
- Airway edema
- Chronic Mucous Plug Formation
- Aiways Remodeling
Exercise-Induced Asthma
Controversial pathogenesis.
The disease may be mediated by water loss from the airway, heat loss from the airway, or a combination of both.
How do you establish the dx of asthma?
- Episodic symptoms of airflow obstruction (wheezing, cough, chest tightness)
- Obstruction is at least partially reversible
- Alternative dx are excluded
- PFTs
- Simple spirometry with post-bronchodilator testing is adequate if COPD is not considered in the differential
How does the typical patient present?
- Periodic cough/SOB/Chest Tightness (often assc with triggers)
- Nocturnal symptoms are common
- Recurrent episodes of SOB assc with a nighttime cough that awakens the pt is a classic presentation.
- “Wheezing” non-specific term with pts
- Childhood/family hx of asthma
What is Bronchoprovocation Testing?
Methacholine-Mannitol Testing
- Methacholine is administered in incremental doses up to a max dose of 16 mg/mL
- Mannitol is also used
- 20% Decreased in FEV1 is considered a positive test result for the presence of bronchial hyperresponsiveness
What is the standard method for evaluating patients with Exercised Induced Asthma?
Exercise Spirometry!
- 6-10 minutes of strenuous exertion at 85-90% of predicted maximal HR and measurement of post-exercise spirometry for 15-30 minutes
- Defined cut off for a positive test = 15% decrease in FEV1 after exercise
When doing PFTs are they definitive?
No, it could be within normal limits if they are having a good day.
Asthma is reversible (controversially speaking)
What might be a better measure than PFTs for asthma
Methacholine
If the test goes up 10% more after albuterol treatment, then we can assume
Asthma, regardless of absolute values
When do you suspect it’s not asthma?
- Long-time smoker (COPD)
- Older than 50 with no prior history
- Symptoms such as palpitations or syncope
- Poor response to asthma treatment
When doing a physical exam on a patient with asthma or suspected asthma, what are you looking for?
- Nasal Polyps
- Chronic Sinusitis/Post-Nasal Drip
- Atopic Dermatitis
- Eczema
- End-expiratory wheezing with prolonged expiration
Are all wheezes indicative of asthma?
No
What can mimic asthma?
- Vocal Cord Dysfunction
2. Cardiac Wheeze
What is Vocal Cord Dysfunction?
- Will commonly have dysphonia and inspiratory wheeze
- Responds poorly to standard asthma therapy
- Dx with Laryngoscopy
What is “Cardiac wheeze”
Thought to be secondary to airways edema and extrinsic compression
When asthma has been confirmed, what do you do?
Identify precipitating factors!!!
What are common allergens that trigger asthma?
- Molds
- Pets
- Insects