Chapter 4 - The atmosphere, oxygen and respiration Flashcards
What are the main components of the respiratory system? (3)
Trachea
Lungs
Pulmonary artery
What is the purpose of the trachea?
To carry air from the hose and mouth to the lungs.
What is the purpose of the lungs?
To absorb oxygen from inspired air and expel CO2 in expelled air.
What (related to oxygen content) remains constant at all altitudes at which common aircraft operate?
Volume percentage of the gasses in ambient air.
“Insufficient oxygen to support the metabolism of the tissues” describes what?
Hypoxia
Hypoxic hypoxia is caused by what?
What is the common reason?
Low saturation levels of oxygen in the blood.
Most common cuse is low partial pressure of atmospheric oxygen, associated with high altitude.
Anaemic hypoxia is caused by what?
What is the most common reason?
Caused by the ability of the blood to carry oxygen.
Likely reasons are carbon monoxide poisoning or low haemoglobin in the red blood cells.
Name symptoms of hypoxia (10)
tingling sensations in the extremities
Irritability / euphoria
Impaired judgement
Headache
Cyanosis
Increased breathing rate
impaired vision
drowsiness
slurred speech
loss of consciousness
What altitude are healthy individuals able to compensate for hypoxic hypoxia?
10,000 - 12,000ft
The three physiological thresholds for hypoxia are:
Reaction threshold:
Disturbance threshold:
Critical threshold:
What altitudes are linked to these?
Reaction threshold:
7000ft
Disturbance threshold:
10,000 - 12,000ft
Critical threshold:
22,000ft
At an altitude of 12,000ft what would start to be affected
Short term memory
Effective performance time is also known as?
Time of useful consciousness.
What is the time of useful consciousness for the following altitudes?
20,000ft
30,000ft
35,000ft
40,000ft
20,000ft - 30min
30,000ft - 1 - 2min
35,000ft - 30 - 90sec
40,000ft - 15 - 20sec
What are the factors that would increase/reduce the severity of hypoxia symptoms? (6)
Rapidness of onset
severity of conditions
level of physical activity
smoking
body weight
general health
________________ is the state of breathing faster and/or deeper than is necessary for the body’s current demand for oxygen.
Hyperventilation