The Effects of Lung Disease 3A Flashcards
Define Tidal volume
The volume of air in each breath (0.4dm^3-0.5dm^3)
Define ventilation rate
The number of breaths per minute (15 breaths)
Define forced expiratory volume
the maximum volume of air that can be breathed out in 1 second
Define forced vital capacity
the maximum volume of air it is possible to breath forcefully out of the lungs after a really big deep breath in
What is TB caused by
tuberculosis bacteria, which when the immune system builds a wall around forms hard lumps called tubercles
TB effects
Infected tissue withing the tubercles dies and the gaseous exchange surface is damaged so tidal volume is decreased (less air can be inhaled with each breath in order to get enough oxygen for respiration ventilation rate is increased )
What is fibrosis
Scar tissue in the lungs, could be caused by infection or inhalation of dust or asbestos
Fibrosis effects
Scar tissue is thicker and less elastic so the lungs are less able to expand and can’t hold as much air as possible so tidal volume is reduced and so is FVC, there’s a reduction in the rate of gas exchange - diffusion rate is slower across a thicker scarred membrane
Faster ventilation rate
What is asthma
Asthma is a respiratory condition where the airways become inflamed and irritated, usually due to an allergic reaction to irritants
Asthma effects
during an asthma attack, the smooth muscle lining the bronchioles contracts and lots of mucus is produced , air flow in and out of the lungs is reduced and so is FEV.
What is emphysema
A lung disease caused by smoking, or long term exposure to air pollution, foreign particles become trapped in the alveoli. This causes inflammation which attracts phagocytes to the area, the phagocytes produce an enzyme which breaks down elastin. Loss of elastin means the alveoli can’t recoil to expel air. It also leads to destruction of the alveoli walls , which reduces their surface area , so the rate of gaseous exchange decreases
