B3- Copd Flashcards
What is rhe biggest risk factor of cood
Genetic suscetibility of smoking (not everyone gets copd from smoking but 50%)
Give some stats
In 2002 was 5th leading seath cause
Preficted by 2030 to be 3rd leading cause of death
Affects 10% of european popn
Costs nhs 800 mill a year
Who talks about the fev and fvc in copd
Johns et al 2014
Why does fev lower
2mm narrowing in copd = obstruction
What does fev1 drop to
80% in mild copd vs 30% in severe
What is the fev1/fvc ratio to diagnose copd
Below 0.7
What are the 2 pathologies of copd
Chronic bronchitis /airway obstructuon
Emphysema / lack of gas exchange
What is chronic bronchitis (kim et al 2013)
Marrowing by 2mm due to infoammation and mucous metaplasia
What % does it affect
14-74% of copd
What increased risk does smoking give on cb
42%
What sorts of things cause mucous metaplasiab (kim 2013)
Inflammatory cells eg th1,th17, neutrophilic oxidative stress, chronic infections and cigarette smoke
How does smoke increqse mucous
Hyperplasia of goblet cells (as well as infections)
What inside neutrophils eg if degranulated by smoke causes mucus metapladia
Neurrophil elastase
What causes reduced elimination of the mucus (kim 2013)
Damaged cilia, weak respiratory muscles, low peak expiratory volume (narrowing)
What is emphysema
Increase suze of air spaces distal to terminal bronchioles due to destruction of alveolar walls delaying exchnage of gases
What sorts of things can damagw alveolar walls
Chromic infectioms which atttact neutrophils elastases and collagenases
Damage to epithelium in emphysema can eventually cause what
Fibrosis scarring and further obstruction of gas exchange
What are the air filled sacs called in emphysema seen on lungs
Bullae
Which law relates to cb and reduced radius of airway to lower wirflwo
Poiseuilles law
Which article discusses smoking and airway obstruction further
Sharafkhaneh et al 2008
Which types of cells does smoke attract initially (sharafkhaneh)
Macrophages (also stimulates epi cels)
What can amcrophages then attract eg cia il8 which allows emphysema
Neutrophils and cd8
Which mmp is a neutrophil collagenase
Mmp 8
What other things can neutrohpiks rleease for emphysema
Proteinase 3
Cathepsins
Gelatinases
Elastases
Smoke inducing airway epithelium can cause release of what sorts of things
Egf,pdgf
What does this allow
Epithelial remodelling (emt), mucous metaplasia
Which artficle disccuses egf and emt into fibroblasts for fibrosis
Jolly er al 2017
How does smoking have link to cancer throogh egf
Forms fibroblasts and emt process involved in cancer
Why does emphysema cause v/q mismatch
Air sac damage and rupturing reduces sa of the lungs so ventilation is lower than perfusioj
Which type of reap failure is this linked to
Type 1 where there is low po2 in arterial blood
How does type 2 didfer
Low po2 but also high co2
Give some examples of type 2 causes
Airway obstruction eg copd, opiates, resp muscle weakness
What type of receptors are tolerated for high pco2 in type 2
Central chemorecpeotrs. So rely on perioheral for hypoxic activation
Which article discusses oxygen induced hypercapnia
Jacono 2013
How would giving oxygen lead to hypercapnis via perioheral
Giving high o2 switches peripheral off. This causes ventilatory depression and co2 is therefore not removed = hypercapnia
Giving oxygen causes the haldene effect. What is this (jacono 2013)
Where xoygen binding to hb causes dissociation of co2 with hb = hypercapnia in arterial blood
Jow is v/q mismatch usually pvercome in copd or poor ventilation
Hypoxic vasoconstriction
How does giving oxygen affect this (jacono)
It causes increased blood flow to the poorly ventilated alveoli = further mismatching
