E&T: Effects of Lung Disease

Question 1

Tidal volume

Answer 1

Volume of air in each breath - usually between 0.4 dm³ and 0.5 dm³ in adults

Question 2

Ventilation rate

Answer 2

Breaths per minute.

Healthy - about 15 breaths.

Question 3

Forced expiratory volume₁

Answer 3

Maximum volume of air that can be breathed out in 1 second.

Question 4

Forced vital capacity

Answer 4

Maximum volume of air it is possible to breathe forcefully out the lungs after a really deep breath in.

Question 5

Volume of air in each breath - usually between 0.4 dm³ and 0.5 dm³ in adults

Answer 5

Tidal volume

Question 6

Breaths per minute.

Healthy - about 15 breaths.

Answer 6

Ventilation rate

Question 7

Maximum volume of air that can be breathed out in 1 second.

Answer 7

Forced expiratory volume₁

Question 8

Maximum volume of air it is possible to breathe forcefully out the lungs after a really deep breath in.

Answer 8

Forced vital capacity

Question 9

Name 4 diseases of the lungs

Answer 9

• Pulmonary tuberculosis (TB)
• Fibrosis
• Asthma
• Emphysema

Question 10

Asthma

Answer 10

Respiratory condition where the airways become inflamed and irritated.

Usually due to an allergic reaction to substances like pollen/dust.

Question 11

Emphysema

Answer 11

Lung disease caused by smoking or long-term exposure to air pollution - foreign particles in smoke or air become trapped in alveoli.

Causes inflammation and attracts phagocytes to area.

Question 12

What happens during an asthma attack?

Answer 12

• Smooth muscle lining in bronchioles contracts.
• Large amount of mucus is produced.
• Causes constriction of airways, reducing air flow in and out of lungs.
• Reduces FEV.

Question 13

Symptoms of asthma:

How can these be relieved?

Answer 13

• Wheezing, tight chest and shortness of breath.
• Relieved by drugs (often inhalers) which relax muscles in bronchioles.

Question 14

What does the inflammation caused by emphysema do?

Answer 14

• Attracts phagocytes - produce an enzyme which breaks down elastin.
• Loss of elastin prevents alveoli recoiling to normal shape and expelling air.
• Destroys alveoli walls, which reduces the surface area of alveoli so gas exchange decreases.

Question 15

What are the symptoms of emphysema?

Answer 15

• Shortness of breath and wheezing.
• Increased ventilation rate as they try to increase amount of air reaching lungs.

Question 16

TB

Answer 16

Immune system cells build a wall around bacteria in the lungs forming small, hard lumps called tubercles.

Question 17

What happens as a result of a person becoming infected with TB?

Answer 17

• Tubercles form.
• Infected tissues inside tubercles dies and gas exchange surface is damaged - tidal volume decreases.
• Causes fibrosis - further reduces tidal volume
• Ventilation increases to get more air into lungs

Question 18

What are symptoms of TB?

Answer 18

Persistent cough

Coughing up blood and mucus

Chest pains

Shortness of breath

Fatigue

Question 19

Fibrosis

Answer 19

Formation of scar tissue in lungs. Can be a result of an infection or exposure to substances like asbestos or dust.

Question 20

What happens as a result of fibrosis?

Answer 20

• Scar tissue is thicker and less elastic.
• So lungs can’t expand as well and can’t hold as much air as normal - reduces tidal volume and FVC.
• Reduces gas exchange - diffusion is slower across scars.
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Question 21

What are symptoms of fibrosis?

Answer 21

• Shortness of breath
• Dry cough
• Chest pain
• Fatigue
• Weakness

Question 22

How do lung diseases make a patient feel tired?

Answer 22

• Rate of gas exchange in alveoli reduced.
• Less O2 able to diffuse into bloodstream.
• Body cells receive less O2
• Rate of aerobic respiration decreases
• Less energy released.