Integrated and comparative respiratory physiology

Question 1

what type of respiratory disease is asthma?

Answer 1

obstructive

Question 2

what are asthma attacks? what triggers them?

Answer 2

triggered by allergens in the environment and cause sudden dyspnoea and difficultly breathing

Question 3

other than asthma attacks, what else does asthma cause?

Answer 3

chronic inflammation of the bronchi and can cause permanent thickening and obstruction of the airways

Question 4

why is it important that the airway stays clear?

Answer 4

so lungs have a normal expiratory capacity

Question 5

what type of respiratory disease is emphysema?

Answer 5

obstructive

Question 6

what is the most common cause of emphysema?

Answer 6

smoking

Question 7

what is the pathophysiology of emphysema?

Answer 7

• Neutrophils invade the lung parenchyma (alveoli) and secrete enzymes that break it down.
• This increases size of alveoli and increases resistance of the lungs.
• Cilia are immobilised by smoke but the trapped irritants cause increased mucus secretion, this will cause chronic inflammation and infection.

Question 8

what type of respiratory disease is COPD?

Answer 8

obstructive

Question 9

what is the most common respiratory condition?

Answer 9

COPD

Question 10

what percentage of the population does COPD affect?

Answer 10

~5%

Question 11

what type of respiratory disease is pulmonary fibrosis?

Answer 11

restrictive

Question 12

what is pulmonary fibrosis?

Answer 12

• where excess fibrous tissue accumulates in the lungs
• gradually the lung parenchyma (alveoli) is replaced with fibrosis tissue.

Question 13

what is asbestosis?

Answer 13

pulmonary fibrosis caused by asbestos

Question 14

define apnoea

Answer 14

Means temporary ceasing of breathing during sleep

Question 15

what is the cause of obstructive sleep apnoea?

Answer 15

• physical obstruction of airways
• During sleep muscles relax and specifically the pharynx collapses and obstructs the airways

Question 16

what is central sleep apnoea?

Answer 16

the respiratory centres can’t initiate breathing

Question 17

what is the name of the breathing pattern that central sleep apnoea can cause?

Answer 17

Cheyne-Stokes breathing

Question 18

what is Cheyne-Stokes breathing?

Answer 18

This pattern involves slow shallow breathing that gradually increases before apnoea

Question 19

what is the pulmonary ventilation at rest?

Answer 19

5-8 L/min

Question 20

what can the pulmonary ventilation increase to during heavy exercise?

Answer 20

100L/min or more

Question 21

what are 3 effects of high altitude (acute) on respiration?

Answer 21

• Acute hypoxia: Caused by short term exposure (minutes to hours)
• Causes “mountain sickness” symptoms include nausea, GI disturbance, headache and psychological disturbances.
• More serious consequences include sleep apnoea but pulmonary oedema can be fatal.

Question 22

what are 5 effects of high altitude (chronic) on respiration?

Answer 22

• Chronic hypoxia: Experienced by people living at high altitude (or mountaineers), who have become acclimatised.
• Increase in respiratory minute volume
• Increase in RBCs and their HB content
• Increase in cardiac output
• Increase in tissue vascularisation

Question 23

what is the respiratory diving response?

Answer 23

• In this response bradycardia, redirection of blood flow to brain and lowered heart rate occur to adapt to the submersion.