Airways resistance Topic 5 – Midterm Flashcards
what is airway resistance?
Airway resistance refers to the opposition to airflow in the respiratory system, specifically in the airways or bronchial tubes.
what is the formula for Airway Resistance
F= change in P/R
Airway resistance is normally very….
low
Airway resistance is dependent on numerous variables:
tube length (fixed)
interactions between gas molecules (variable)
airway radius (regulated)
what Physical Factors influence Airway Resistance
transpulmonary pressure
Pressure can affect resistance and flow
mucous accumulation
Can decrease the diameter of airway
what Neurological Factors influence Airway Resistance
parasympathetic (acetylcholine) constricts (↓ radius)
Epinepherine = dilates
histamine = constricts (allergic reactions)
how does Epinepherine work
Epinepherine works by relaxing the muscles around the airways so that they open up and you can breathe more easily
what are the two OBSTRUCTIVE DISEASES airway diseases
Asthma
Chronic Obstructive Pulmonary Disease (COPD)
what is asthma
inflammation of the airways
asthma is hyperresponsiveness to certain triggers like
exercise
smoke
Pollutants
how is Asthma treated
anti-inflammatory drugs
leukotriene inhibitors
Bronchodilators
what are leukotriene inhibitors
medications that block the effect of leukotrienes or stop your body from producing them. These drugs are used to prevent or lessen the symptoms of: Allergies (allergic rhinitis). Allergic asthma
what do Bronchodilators do
relax the airways
mimic epinepherine (often beta-2 agonists)
inhibit acetylcholine
what is Chronic Obstructive Pulmonary Disease (COPD)
cause the airways to narrow and the lungs to lose elasticity, making it difficult to empty air from the lungs
what are the Two different types of COPD(often interrelated)
Emphysema
chronic bronchitis
what is Emphysema
destruction and collapse of smaller airways and also the pulmonary vascular system
what is chronic bronchitis
Chronic inflammation of airways
excessive mucous production in smaller airways
do the same agents cause both emphysema and chronic bronchitis?
yes
what is the main cause of COPD and is thought to be responsible for around 9 in every 10 cases.
smoking
what is the goal of treatments for both COPD and asthma
trying to decrease airway resistance, but its not always the same effect in both
Asthma and COPD result in
increased airway resistance
decreased air flow rate
Increased work of breathing
Compromise gas exchange
Impaired oxygenation of blood
