obstructive airway disease Flashcards
- Describe the symptoms and clinical patterns of asthma, and show how this affects the O2 alveolar gas.
Air becomes trapped in the alveoli (air sacs at the end of the bronchioles). This trapped air cannot provide for the proper exchange of oxygen and carbon dioxide. Trapped air leads to hypoxia (low oxygen content) in the body. Air trying to pass through the narrowed tubes filled with mucus may produce wheezing.
Describe the term ‘shunt’.
this is a condition where blood vessels bypass your lungs and the blood is not properly oxygenated. This results in a lower than normal level of oxygen in your blood. occurs during severe acute infective exacerbation
Features of obstructive lung disease
There is airflow limitation, PEFR is reduced, FEV1 is reduced, FCV is less reduced, FEV1 is less than 70% of FVC
bronchial asthma
inflammation and oedema, mucus and plasma exudation
morphological changes in chronic bronchitis
cough productive of sputum of 2 years in at least 3 consecutive months of the year
large airways- mucosa gland hyperplasia, goblet cell hyperplasia
small airways- goblet cells appear, inflammation and fibrosis in long standing disease
morphological changes in chronic bronchitis
cough productive of sputum most days in at least 3 consecutive months of the year for 2 or more years
large airways- mucosa gland hyperplasia, goblet cell hyperplasia
small airways- goblet cells appear, inflammation and fibrosis in long standing disease
emphysema
increase beyond normal in the size of airpspaces distal to the terminal bronchiole arising from dilation or destruction of their walls- loss of alveolar attachments is most important
centri-acinar emphysema
begins with bronchiolar dilation, then alveolar tissue is lost
hypoxic cor pulmonale
pulmonary hypertension
chronic- hypertrophy of right ventricle resulting from disease affecting the function or structure of lung
how does smoking increase emphysema
increases elastase which leads to tissue destruction.