Obstructive Lung disease overview Flashcards
Diseases which affect the parenchyma are
Restrictive (Normal Ratio)
Diseases which affect the airways are
Obstructive (Reduced Ratio)
The asthma triad consists of
Reversible airways obstruction, airway inflammation and airway hyper responsiveness
The asthma triad results in
Bronchoconstriction, chronic inflammation and airway remodelling
Histological changes seen in asthma
Thickening of the basement membrane, collagen deposition and smooth muscle hypertrophy
Define the Asthma inflammatory cascade
Genetic disposition -> Eosinophilic inflammation -> presence of inflammatory mediators -> Twitchy smooth muscle ->
Immune response to asthma
Chronic eosinophilia
Immune response to COPD
Chronic Neutrophilia
Outline the basic pathogenesis of COPD
Cigarette smoking causes endothelial damage which activates tissue macrophages. These macrophages then release Il-8 and other cytokines which stimulate a neutrophil response. These release proteases which degrade alveolar walls (emphysema) and cause mucus hyper secretion (chronic bronchitis).
Henry’s law
The amount of O2 dissolved in blood is proportional to the partial pressure of o2 in the system.
A right shift in the O2 curve means
Less affinity for O2 (haemoglobin dumps O2) i.e. in muscle tissue.
A left shift in the O2 curve means
More affinity for O2 (haemoglobin picks up O2) i.e. at the alveoli
Increase in pH (alkalosis) causes
Left shift in curve
Increase in CO2 (hypercapnia) causes
Right shift in curve
Increase in temperature (fever) causes
Right shift in curve
