Asthma Roop/Raja Flashcards
What is wheezing?
Whistling sound upon expiration because of an obstruction
What are the primary causes of wheezing?
-Asthma
-Bronchitis
-COPD
What might a physical exam show for a pt wheezing, anxious, and SOB?
-wheezing is more prominent on exhalation and there is an extended forced expiratory phase
-chest anteroposterior diameter appears large for age and size
-nasal mucosa is edematous, and the pharynx is coated w/ a clear postnasal discharge
A pt who is wheezing may be prescribed a beta-2-adrenergic agent administered by an inhaler, and the symptoms quickly subside. Beta 2 agonists replicate the actions of the catecholamines. Name the catecholamines and what are the actions of beta 2 agonists?
Catecholamines = NE and Epi
action= dilation by relaxing smooth muscle on multiple organs
What causes the large diameter of the anteroposterior chest for some patients wheezing?
-Air trapped in lungs → increases lung size → pushes chest out
-When you inspire→ chest wall pushes out (issue is that we can’t get the air out bc muscles are contracting)
What are the 3 types of beta receptors?
beta 1, 2, and 3
Do beta 1 receptors increase or decrease cAMP? What organs are affected and how?
beta 1 receptors increase cAMP
affects heart (increase co) and kidneys (increase renin)
Do beta 2 receptors increase or decrease cAMP? What organs are affected and how?
beta 2 receptors increase cAMP
smooth muscle relaxation–> lungs, blood vessels, GI tract, bladder, uterus, liver
will increase diameter of lungs and blood vessels
will decrease peristalsis and digestion
bladder will decrease urination
liver will make glucose
Do beta 3 receptors increase or decrease cAMP? What organs are affected and how?
beta 3 receptors increase cAMP
affects adipose tissue and bladder
there will be lipolysis and decreased urination
What does Gs mean?
increases cAMP
Beta1= heart= _________
Beta2= lungs= ________
1 heart, 2 lungs
What are the pulmonary function tests?
-spirometry test
-methacholine challenge test (bronchoprovocation test)
What is spirometry?
-Measurement of lung capacity
-Expiring into tube and spirogram measures
-Only exhalation
-Measuring how much air you can breathe out in one forced breath
What is a methacholine challenge test and what is methacholine?
-Methacholine is a parasympathomimetic bronchoconstrictor used to diagnose bronchial hyperreactivity in subjects who do not have clinically apparent asthma
-during the test, pt will be asked to inhale doses of methacholine, a drug that can cause narrowing of the airways. A breathing test will be repeated after each dose of methacholine to measure the degree of narrowing or constriction of the airways
-Methacholine is administered sequentially in increasing conc.
-Methacholine is also known as Acetyl-β-methylcholine, which is a synthetic choline ester that acts as a non-selective muscarinic receptor agonist in the parasympathetic nervous system (airways are obstructed and they try to get air out)
What can you expect during a spirometry test?
A pt undergoes a methacholine test. The results show hyperreactive bronchoconstriction with decreased FEV1, decreased forced vital capacity and increased residual volume. Flow/volume loop demonstrates scooping. What is FEV1 and what is scooping?
forced expiratory volume (1 = first second)
FEV1 = vol. of air that can be expired in the first second of a forced maximal expiration
Is asthma obstructive or restrictive?
obstructive (fibrotic lung disease would be restrictive)
What is forced vital capacity (FVC)?
volume of air that can be forcibly expired after a maximal inspiration = TV +IRV+ERV
FEV1 is normally _____% of forced vital capacity. What is the equation here?
80%
FEV1/FVC = 0.8
In _____________ lung disease, FEV1 is reduced so FEV1/FVC is decreased
obstructive
Asthma is a chronic inflammatory disease of the airways that includes….
- Airway hyperresponsiveness (airway narrowing) to specific triggers
- Chest tightness
- Variable airflow limitation
- Coughing
- Wheezing
What are some asthmatic triggers?
-Pollen
-Dust
-Pet hair
-Grass
-Shellfish and nuts- breathing it in, not eating
-Smoking/ second hand smoke
What type of epithelium lines the majority of the airways?
Pseudostratified ciliated columnar epithelium with goblet cells = RESPIRATORY epithelium
Goblet cells produce mucus for what purpose?
to trap pathogens/allergens