Physiology 3.4

Question 1

Describe the difference between obstructive and restrictive lung diseases.

Answer 1

Obstructive lung diseases involve obstruction to air flow, particularly on expiration, while restrictive lung diseases involve a restriction of lung expansion.

Question 2

Do obstructive lung diseases primarily affect air flow during inspiration or expiration?

Answer 2

Obstructive lung diseases primarily affect air flow during expiration due to compression of the airways.

Question 3

Define chronic obstructive pulmonary disease (COPD) and provide examples of conditions falling under this category.

Answer 3

COPD includes chronic bronchitis and emphysema. Asthma is not normally classified as COPD.

Question 4

How does asthma differ from chronic bronchitis in terms of airway narrowing?

Answer 4

Asthma involves inappropriate constriction of bronchial smooth muscle, while chronic bronchitis involves inflammation of the bronchi, both leading to narrowing of the airways.

Question 5

Describe the impact of emphysema on air flow and lung elasticity.

Answer 5

Emphysema involves destruction of alveoli and loss of elasticity due to breakdown of elastic fibers, leading to reduced force for air expulsion and decreased elastic recoil.

Question 6

What are some examples of obstructive lung diseases?

Answer 6

Examples of obstructive lung diseases include asthma, chronic bronchitis, and emphysema.

Question 7

How do obstructive lung diseases differ from restrictive lung diseases in terms of airway obstruction?

Answer 7

Obstructive lung diseases involve obstruction to air flow due to compression and narrowing of airways, while restrictive lung diseases involve a restriction of lung expansion.

Question 8

Describe the impact of chronic bronchitis on airway narrowing.

Answer 8

Chronic bronchitis involves inflammation of the bronchi, leading to a narrowing of the airways and compromised air flow, particularly on expiration.

Question 9

What is the estimated global prevalence of moderate to severe COPD?

Answer 9

Approximately eight million people worldwide are estimated to have COPD in a moderate to severe form.

Question 10

Describe the prevalence COPD in the UK population.

Answer 10

About one percent of the UK population has moderate to severe COPD, but the actual prevalence is likely higher, especially among individuals over the age of 75.

Question 11

Define restrictive lung diseases and their impact on lung compliance.

Answer 11

Restrictive lung diseases involve a restriction of lung expansion and a loss of lung compliance, meaning more effort is needed in inspiration to achieve the same change in lung volume.

Question 12

Do obstructive lung diseases impact inspiration or expiration?

Answer 12

Obstructive lung diseases tend to impact more on expiration.

Question 13

How does fibrosis contribute to restrictive lung diseases?

Answer 13

Fibrosis involves the formation of fibrous tissue around the elastic tissues in the lungs, creating a stiff lung that is difficult to stretch open during inspiration.

Question 14

Describe infant respiratory distress syndrome and its impact on lung expansion.

Answer 14

Infant respiratory distress syndrome is caused by inadequate surfactant production, leading to an increase in surface tension and a lung that is less willing to expand on inspiration.

Question 15

Define pulmonary edema and its impact on lung expansion.

Answer 15

Pulmonary edema involves fluid building up around the alveoli, creating pressure that resists lung expansion.

Question 16

What is a pneumothorax and how does it affect the relationship between the lung and the chest wall?

Answer 16

A pneumothorax occurs when air is introduced to the pleural cavity, pushing apart the parietal pleural membrane from the visceral pleural membrane, leading to a lung that is no longer related to the chest wall and the diaphragm.

Question 17

Describe relationship between the lung, chest wall, and diaphragm during pneumothorax.

Answer 17

The lung becomes independent of the chest wall and diaphragm, leading to a loss of lung expansion.

Question 18

What is spirometry and what does it measure?

Answer 18

Spirometry is a technique used to measure lung function, specifically measuring the volume of air inspired and expired.

Question 19

Define static and dynamic measurements in the context of spirometry.

Answer 19

Static measurements only consider the volume of air exhaled or inhaled, while dynamic measurements also consider the time taken to inhale or exhale the air.

Question 20

How are lung function tests commonly diagnosed, and what is a commonly used lung function test?

Answer 20

Lung function tests are commonly diagnosed using spirometry, and a commonly used lung function test is the FEV1 to FVC ratio.

Question 21

Describe the information available in the British Thoracic Society link related to spirometry.

Answer 21

The link provides accessible and easy-to-read information about spirometry, including normal values for different individuals at different stages of life.

Question 22

What are the factors that can affect normal values in spirometry?

Answer 22

Normal values in spirometry can vary depending on sex, age, and height.

Question 23

Do static measurements or dynamic measurements tend to be more helpful in spirometry?

Answer 23

Dynamic measurements tend to be more helpful in spirometry as they consider both the amount of air inhaled or exhaled and the time taken to inhale or exhale the air.

Question 24

Describe the volumes measured in spirometry, including tidal volume.

Answer 24

The volumes measured in spirometry include tidal volume (the volume of air breathed at rest and quietly), inspiratory reserve volume, expiratory reserve volume, and total lung capacity.

Question 25

Describe the inspiratory reserve volume.

Answer 25

The inspiratory reserve volume is the extra volume of air that can be breathed in with maximum effort to fill up the lungs beyond normal capacity.

Question 26

What is residual volume and why is it important?

Answer 26

Residual volume is the volume of air that remains in the alveoli even after maximum expiration. It is important for preventing alveolar collapse and allows for gas exchange between breaths.

Question 27

Do spirometry measurements include residual volume?

Answer 27

No, spirometry measurements do not include residual volume.

Question 28

Define FEV1 and FVC the context of lung function tests.

Answer 28

FEV1 refers to forced expiratory volume in one second, while FVC refers to forced vital capacity. FEV1 measures the volume of air expired in the first second of a forced expiration, while FVC measures the total amount of air expired.

Question 29

How is the FEV1 to FVC ratio calculated and what does it indicate in a healthy adult male?

Answer 29

The FEV1 to FVC ratio is calculated by dividing the FEV1 by the FVC, and in a healthy adult male, it is typically around 80 percent.

Question 30

Describe the difference between vital capacity and forced vital capacity.

Answer 30

Vital capacity is the maximum amount of air that can be exhaled after maximum inhalation, while forced vital capacity measures how fast the air can be exhaled after maximum inhalation.

Question 31

Describe the normal values for FEV1 and FVC in a fit young, healthy adult male.

Answer 31

The average FEV1 is four litres and the FVC is five litres.

Question 32

How do the normal values for FEV1 and FVC vary with age, height, and health?

Answer 32

The values vary depending on age, height, and health.

Question 33

Define the ratio of FEV1 to FVC in spirometry.

Answer 33

The ratio of FEV1 to FVC remains about 80 percent regardless of sex, height, or age.

Question 34

Describe the impact of obstructive lung diseases on the FEV1 to FVC ratio.

Answer 34

Obstructive lung diseases result in a reduced FEV1, reduced FVC, and a significantly reduced FEV1 to FVC ratio.

Question 35

What happens to the FEV1 and FVC in restrictive lung diseases?

Answer 35

In restrictive lung diseases, both the FEV1 and FVC are reduced, but they are reduced in proportion to a much greater extent than in obstructive lung diseases.

Question 36

How does obstructive lung disease affect the rate of air exhalation?

Answer 36

In obstructive lung diseases, the rate at which air is exhaled is much slower due to increased airway resistance or loss of elastic recoil in the alveoli.

Question 37

Describe the difference in FEV1 to FVC ratio between obstructive and restrictive lung diseases.

Answer 37

In obstructive lung diseases, there is a significant fall in the FEV1 to FVC ratio, while in restrictive lung diseases, the ratio remains constant or may even increase.

Question 38

Define compliance in the context of physiology.

Answer 38

Com describes the stretchability of lungs, specifically how much lung volume changes for any given change in pressure.