Hypoxia and Hyperventilation

Question 1

What are the two main gases and their percentages in the atmosphere?

Answer 1

Nitrogen 78%, Oxygen 21%, Other 1%( Argon, Carbon Dioxide, etc)

Question 2

T or F: The amount of available oxygen decreases as we go up in altitude

Answer 2

True, the higher we go, the less oxygen molecules there are

Question 3

T or F: The percentage of oxygen decreases as we go up in altitude

Answer 3

False, the relative amount of oxygen is a constant (Always 21%, but partial pressure decreases)

Question 4

What is the temperature lapse rate when ascending altitude?

Answer 4

-2 degrees Celsius per 1000 ft

Question 5

What is the primary function of the respiratory system?

Answer 5

To intake oxygen and remove carbon dioxide (inhale O2, exhale CO2)

Question 6

What is Hypoxia?

Answer 6

A deficiency of oxygen in the blood, cells, or tissue to cause a functional impairment

Question 7

What are the 4 types of Hypoxia?

Answer 7

Hypoxic (Altitude), Stagnant, Hypemic (Anemic), Histotoxic

Question 8

What is Hypoxic Hypoxia?

Answer 8

Altitude Hypoxia, lack of available oxygen molecules in the air (can exist at all levels, effects don’t show until 5000 ft especially at night)

Question 9

What is Stagnant Hypoxia?

Answer 9

Blood flow becomes compromised, sufficient oxygen cant get to cells. (Stagnant means diminished flow, can be caused by G maneuvers)

Question 10

What is Hypemic/Anemic Hypoxia?

Answer 10

Blood cells cant carry oxygen molecules (Carbon monoxide poisoning, CO2 has 250 times more affinity than oxygen, thus it competes with it)

Question 11

What is Histotoxic Hypoxia?

Answer 11

Target cell is abnormal, likely due to a toxin (Alcohol, cyanide)

Question 12

Match the following scenarios with their types of hypoxia:
- G force maneuver
- Alcohol
- Carbon monoxide poisoning
- 10,000 ft altitude

Answer 12

• G force (Stagnant)
• Alcohol (Histotoxic)
• Carbon monoxide (Hypemic)
• 10,000ft (Hypoxic)

Question 13

What are 4 Objective signs of Hypoxia?

Answer 13

Cyanosis (blue lips, fingernails
Mental confusion
Euphoria
Decreased reaction time

Question 14

T or F: Decompression of pressure cabin is the most common incident of Hypoxia

Answer 14

True (32%) , next is Failure of Oxygen regulator (25%), then Other (17%)

Question 15

What are 4 Subjective signs of Hypoxia?

Answer 15

Air hunger
Headache
Dizziness
Nausea

Question 16

What are 3 factors that can influence hypoxia?

Answer 16

Fitness
Rate of Ascent
Acclimatization

Question 17

What is your EPT at 18,000 ft? 25,000 ft? 50,000 ft?

Answer 17

18,000: 20-30 mins
25,000: 3-5 mins
50,000: 9-12 seconds

Question 18

What is hyperventilation?

Answer 18

Exceeding the normal ventilation rate. Breathing out so fast that your body can’t keep up and removes too much CO2 from your body, potentially causing unconsciousness

Question 19

What are 3 causes of Hyperventilation?

Answer 19

• Stress (Physical, emotional, environmental)
• Improperly sized equipment
• Hypoxia

Question 20

T or F: The objective and subjective effects of Hyperventilation and Hypoxia are largely similar

Answer 20

True

Question 21

What is the one different effect in Hyperventilation that is not present in Hypoxia?

Answer 21

Tetany (involuntary muscle spasms)

Question 22

According to the BGA, at what cabin altitude will supplemental oxygen be used at all times?

Answer 22

> 10,000 ft

Question 23

According to the BGA, if you are operating at cabin altitude >8000 ft for >4 hours you shall ________________

Answer 23

Use supplemental oxygen, with a minimum interval of 60 minutes below 5000 ft due to risk of Acute Mountain Sickness

Question 24

What is Dalton’s Law?

Answer 24

The total pressure of a mixture of gases is equal to the sum of partial pressures PT = P1 + P2 + P3. P(760) = P(N) + P(O) + P(Other)

Question 25

At what altitude does the atmospheric pressure half?

Answer 25

18,000 ft (Becomes 50% of sea level density, 15 mmHg)

Question 26

What are the 5 phases of respiration (VDTDU)

Answer 26

Ventilation
Diffusion
Transport
Diffusion
Utilization

Question 27

What are the two circulatory subdivisions called?

Answer 27

Pulmonary (heart and lungs) and Systemic (rest of body)