November 13, 2023 Flashcards
what is the difference between compliance and elasticity in the lung
Compliance refers to the ability of the lungs to stretch and expand in response to changes in pressure. It is a measure of the ease with which the lungs can accommodate changes in volume.
Elasticity refers to the ability of the lung tissue to return to its original shape after being stretched or compressed. It is a measure of how well the lungs recoil or spring back to their resting state.
what do the results of a FEV1 test using spirometry show in regards to someone who is:
Normal:
Obstructive lung disease:
Restrictive lung disease:
Normal: >80% of VC expired within first second
Obstructive lung disease: FEV1 < 80% VC
Restrictive lung disease: lower inspiration amount, however greater than 80% FEV1
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Describe the characteristics that a Normal, healthy lung has:
bronchiolar walls:
Alveoli amount:
surface area for diffusion:
➢ Strong bronchiolar walls
➢ Many small alveoli
➢ High surface area for diffusion
Describe the characteristics that a Emphysematous lung has:
bronchiolar walls:
Alveoli amount:
surface area for diffusion:
➢Weak bronchiolar walls
➢ Disrupted alveoli
➢ Markedly reduced surface area for diffusion
➢ Less surface area can represent a diffusion limitation; a very high PIO2 (and therefore PAO2); using inhaled 100% O2 is useful to ensure Hb saturation
Describe Breathing Pattern (ex: VT) During Exercise (healthy vs. copd)
COPD patients have a truncated (smaller) tidal volume in response to exercise; so they must rely more on an increase in breathing frequency to generate increases in ventilation (panting-like breathing); increased work of breathing
Healthy individuals can use a greater fraction of their VC during exercise
what is the Borg scale
Borg scale: index of laboured breathing (dyspnea), the rating of perceived exertion (RPE)
how can someone with COPD increase their VE during exercise to match that of someone who is healthy
increase breaths/min
ex:
Healthy: 2000mls/b x 20 b/min
COPD: 1000 mls/b x 40 b/min
In evaluating lung diseases, Exercise Testing might be used to:
reveal underlying pathology that might not be evident at rest
Indicates the extent of:
➢ dyspnea,
➢Hb saturation
➢hypoxemia or hypercapnia
and evaluates the lactate threshold as an index of the quality of the aerobic system during exercise
In pulmonary rehabilitation, exercise training can:
hint:
➢peripheral muscle adaptation
➢respiratory muscle adaptation
➢reduced perceived exertion
➢ Increased lactate threshold
➢ Increased work capacity and sense of well being
➢ Increase in FEV1
➢ Increase in VE capacity
➢ Decrease in VE during submaximal exercise (reduce perceived exertion) and perceived difficulty of exercise)
what is asthma
An obstructive disease of large airways characterized by:
- Increased sensitivity to a variety of environmental allergens, a result of high amounts of immunoglobulin E (IgE) which triggers the response
- Inflammation
what are Risk factors of asthma
➢ Smoke, dust, pet exposure (chronic)
➢ Genetic predisposition: 1 parent = 25% chance, 2 parents = 50% chance
➢ Chest infections, cold air
what are Goblet cells:
are named for their goblet or flask-like shape and are responsible for producing and secreting mucus
Mast cell
known for their role in the body’s allergic and inflammatory responses
Explain the Mechanisms Involved in Airway Obstruction
- Inhaled allergen binds to Antibody receptor (IgE) and activates degranulation (exocytosis)
- Causing Histamine to be released from the cell into ECF and act on the H1 receptor of both bronchial smooth muscle to increase constriction and leukocytes where it activates enzyme phospholipase A2
- phospholipase A2 breaks down phospholipids into arachidonic acid
- arachidonic acid converted into leukotrienes which is secreted from the cell to promote inflammation
why do Leukocytes produce leukotrienes
Leukocytes produce leukotrienes in response to histamine to promote inflammation
