Lung Disease

When the bronchioles become inflammed and air ways become restricted 

Causes - 

• Exposure to pollutions
• May inherit 

Effects on the lungs/ gas exchange surfaces

• Inflammation of epithelial cells and tissue lining of the bronchioles narrowing the lumen
• Smooth muscle contracts in the bronchioles narrowing lumen
• Mucus is secreted increasing the diffusion pathway reducing gaseous exchange
• Decreases the ability for entry of air so lower differences in as concentrations meaning reduced diffusion

Treatment

Bronchiodilators - cause muscle to relax and the diameter to increase increasing gasesous exchange

When epithelial cell lining become thicker in respone to lung damage

Causes

• Inhaling microscopic particles 
• pollution 

Effect on lungs

• Loss of elasticity due to fibre like scar tissue, so less stretch and recoil

Effect on gaseous exchange surface

• Decreased ability to inflate or deflate lungs, reduced volume during ventilation meaning lower differences in gas concentrations = less o2 absorbed leading to a shortness of breath
• Thickened airways means thicker diffusion pathway so longer diffusion pathway

Treatment - Increase amount of oxygen to increase 02 concentration in the lungs

Causes

• Smoking
• Air pollutions 

Effect on the lungs

• Loss of elastic fibres due to response to allergens cigarette smoke
• WBC release elactase ---> elastin -  the connective tissue in the lungs. No stretch or recoil making ventilation more challenging
• Breaks down the alveoli walls decreasing surface area for gaseous exchange. 

Effect of gaseous exchange suface

• Decreased ability to inflate or deflate  lungs as lower differences in gas concentrantions
• Less surface area for diffusion because of the break down or alveoli walls

Treatment - more oxygen to increase 02 concentrations in the lungs meaning maintain concentration gradient = faster rate of diffusion

Causes

• Mycobacterium turberculosis

Effect on the lungs

• Bacteria multiplies in the lung tissues - small lumps in upper part where O2 is greatest
• Sets up imflammatory response of the immune system - sends macrophages to engulf and digest baacterium
• Can cause formation of cavities

Effect on gaseous exchange

• Formation of cavities decreases SA for gas exchange so less diffusion
• Fluid and scarring makes the diffusion pathway longer meaning O2 takes longer to diffuse in and out of the lungs so less diffusion

Treatment  3 - 4 different Antibiotics perscribed for 6-9 months. Taken everyday and continued for the full course.