Week 6 Flashcards
Four common types of obstructive pulmonary diseases
COPD
Asthma
OSA
Bronchiectasis
COPD
- epi
- risk factors
- 4th leading cause of moridity/mortality
- Smoking, alpha-1-antitrypsin deficiency
Discuss factors that induce COPD
- Oxidative stress
- Inflammation
- Anti-protease imbalance
- ROS cause more cell damage and destruction -> more inflammation
- Inflammatory cells, release of inflammatory mediators causing epithelial damage and release of more cytokines
- anti-proteases stop proteses from breaking down a protein, and in case of COPD we want to stop elastase from breaking down elastin
NRF2 gene in COPD
- what is it?
- what happens if you knock it out
- gene that codes for transcription factors that help with anti-oxidants; help fight oxidative stress
- you remove someone’s ability to fight oxidation, they are more susceptible to emphysema and other lung diseases in general
Types of Emphysema
- Centriacinar
- Panacinar
- Distal acinar
- Irregular emphysema
- More common; Basically the proximal portion of each acinus is involved
- Panacinar: Does NOT mean all the acini are involved, Entire acinus of the involved acini is involved, Seen in pts with alpha-1 antitrypsin deficiency.
- Distal acinar: believed to be involved in spontaneous pneumothorax, particularly in young people, b/c peripherally located, Associated with scarring
- Irregular emphysema: Associated with scarring
Histo changes in emphysema
- what is big change
- mechanism
- what does that cause?
- Destroying walls of alveoli (acinar spaces) and you end up with big empty spaces
- destroying alveolar walls and there is little fibrosis involved, so you end up with alveoli that are gone and large air spaces
Clinical definition of chronic bronchitis
cough productive of sputum for over three months’ duration during two consecutive years and the presence of airflow obstruction
What happens during chronic bronchitis
- Mucus Hypersecretion; how does this happen? what happens over time? mechanism?
- Inflammation
- Infection
- Associated with hypertrophy of submucosal glands in the trachea and bronchi, With time there is also a marked increase in goblet cells in small airways—small bronchi and bronchioles—leading to excessive mucus production that contributes to airway obstruction; You’re inhaling smoke/pollutants and your lungs are secreting mucus to try and clear this stuff out -> Under that stimulation of mucus hypersecretion, your body creates more mucus glands to try and keep up
- Inflammation: Chronic inflammation –> can lead to fibrosis
- Infection: Not really a cause but happens to be associated with it
Histo changes in chronic bronchitis
Goblet cell hyperplasia which increases thickness of mucosal gland layer; chronic inflammation and fibrosis
What is the reid index?
- ratio of the thickness of the mucous gland layer to the thickness of the wall between the epithelium and the cartilage
- the bigger it is the worst the bronchitis
Signs and symptoms of emphysema?
- breathing- when? what does it do?
- weight loss? why?
- cough
- Pursed lip breathing; late stages; creates positive pressure ventilation to open up the smaller airways
- Fatigue
- Cachexia if this a chronic issue; can be caused from energy expenditure with breathing
- cough not as prominent b/c it’s deeper in the airways and you’re not trying to clear the mucus.
How can the kind of puff affect which disease the pt gets?
- if it’s more of a shallow puff, then smoke may not be penetrating quite as deeply into the lungs. So they end up with a little bit more damage to the bronchi.
- For people that are taking really deep puffs, the smoke may get deeper into the lungs, and so they present more with emphysema.
Signs and symptoms of chronic bronchitis?
- persistent cough
- productive sputum
- dyspnea
Blood gas level in COPD
- Increased CO2: hypercapnia
- Decreased O2: hypoxemia
Spirometry and COPD
- FEV1
- FVC
- Ratio
- TLC and RV
- FEV1: decrease -> She has difficulty exhaling, and collapsed alveoli
- FVC: might not be quite as affected first, but a little later on will see it go down
- Ratio: decreased; FEV1 decreases disproportionately compared to FBC. Both values go down, but FEV1 goes down more
- TLC and RV: Increased due to air trapping
Flow volume curve with obstructive
- in later stages of obstruction, we get that air trapping, and not as much volume coming out.
- the overall volume and residual volume goes up, but it’s stuck in the lungs.
Imaging in COPD
- what imagining technique would you use?
- results?
- x-ray
- hyper-inflated lungs, vasulature is shown
Treatment of COPD exacerbations
- what happens if SABA is not working?
- What happens if those both aren’t working?
- oxygen, albuterol, IV corticosteroids
- add a SAMA -> triotropium
- corticosteroid
Beta 2 agonist signaling at beta adrenergic receptors
it’s a multimeric protein, GalphaS subunit. If we agonize that, we are prolonging the cascade so we keep generating cAMP, upregulate PKA and then cause an increase K+ channel activation, downregulate PLC IP3, and increase the Na+/Ca+ATPase
Why would we need antibiotics to treat COPD?
- why would this happen
an infection will cause exacerbation and trapping in there. So we need to eliminate the infectious process to get them over that up
- Steroids increase the risk for infection; and there is not effective clearing of mucus secretions which can block the ciliated cells which would stop the functioning of the muco-ciliary elevator and lesses the defenses of the airway which raises increase in risk of infections with COPD.
theophylline’ MOA
- It blocks the degradation of cAMP, increases PKA activity for the relaxation
Different types of asthma
- atopic
- non-atopic
- drug induced
- occupational
- IgE mediated hypersensitivty triggered by allergens; smoking
- inflammatory reaction triggered by viruses or inhaled air pollutants; URI
- aspirin -> inhibits PGE2
- triggered by fumes, organic and chemical dusts, gases, or other chemicals
Pathogenesis of Asthma
- genes
- airway inflammation
- early reaction
- late phase reastion
- genetic pre-disposition –> TH2/IgE response to allergens
- potent inflammatory mediators remodeling of airway wall
- bronchoconstriction (caused by leukotrienes) , increase mucus production, variable degree of vasodilation, and increased vascular permeability
- leukocytes (eosinophils, neutrophhils, and more T cells)
Signs and symptoms of asthma
- when do sxs occur?
- recurrent episodes of wheezing, dyspnea, and chest tightness
- at night or in the morning