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Flashcards in Altitude Physiology Deck (47):
1

What are the physical divisions of the atmosphere?

Troposphere - Extends to an Alt. of 30,000 ft. at the poles and 60,000 ft. at the equator Tropopause - boundary between troposphere and stratosphere Stratosphere - tropopause to about 50 miles upward. Ionosphere - end of stratosphere upward to 600 miles Exosphere - end of ionosphere to about 1200 miles (true space)

2

What are the physiological zones of the atmosphere

Efficient zone Deficient zone Space equivalent zone

3

Efficient zone

sea level to 10,000 ft

4

Deficient zones

10,000 ft to 50,000 ft

5

Space equivalent zone

above 50,000 ft

6

What are the functions of the circulatory system?

Transports O2 and nutrients to cells throughout the body Transports metabolic waste products to organ removal sites Assists in temperature regulation Acid-base balance

7

What carries O2 to cells

red blood cells

8

What are the functions of respiration?

Provide O2 to cells, Remove carbon dioxide from cells Assist in maintaining body temperature, Assist in maintaining body acid-base balance

9

Inhalation

The active phase of respiration. Movement of air into the lungs when the chest wall expands and the diaphragm moves downward.

10

Exhalation

The passive phase of respiration. Movement of air out of the lungs when the chest wall collapses and the diaphragm relaxes.

11

What happens to respiration during pressure breathing at altitude

The active and passive phases of respiration are reversed. In some indivduals, this can lead to hyperventilation and unconsciousness

12

Hypoxia

Oxygen deficiency sufficent to impair performance

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What are the four types of Hypoxia

Hypemic Stagnant Histotoxic Hypoxic

14

Hypemic Hypoxia

Reduction in O2 carrying capability of red blood cells; e.g. carbon monoxide

15

Stagnant Hypoxia

Reduction in blood flow; e.g. positive G maneuvers

16

Histotoxic Hypoxia

Interference with the use of O2 by the body tissues; e.g. cyanide poisoning

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Hypoxic Hypoxia

Insufficient pressure of O2 in the air; e.g. flying at altitude

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Symptoms

What you feel

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Signs

What you see in others

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Stages of Hypoxia

  • Indifferent stage
  • Compensatory stage
  • Disturbance stage
  • Critical stage

(ICDC) 

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Indifferent stage

sea level to 10,000 ft, usually no symptoms noted in a healthy individual.

22

What is the only significant effect of mild hypoxia at the indifferent stage?

Night vision deteriorates at about 4,000ft.

23

Compensatory stage

10,000 to 15,000 ft;

mild effects begin to appear, but the individual can usually overcome the effects or compensate for the deficits

24

Disturbance stage

15,000 to 20,000 ft;

most of the symptoms of hypoxia will appear, and will increase in severity with absolute altitude, time at altitude, and rate of ascent

25

Critical stage

20,000 ft and above

severe effects: loss of consciousness, convulsions, and death

26

What is hyperventilation

Abnormal loss of CO2 from the blood

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Causes of hyperventilation

Causes are usually: - emotional; fear, apprehension, excitement - pressure breathing, - hypoxia

28

Symptoms of Hypoxia

Symptoms are observable by the individual aircrew member. They vary from one person to the next: Air hunger or breathlessness / Apprehension (anxiety) Fatigue / Nausea / Headache / Dizziness / Hot and cold flashes / Euphoria / Belligerence (anger) Blurred vision Tunnel vision / Numbness / Tingling / Denial

29

Signs of Hypoxia

Signs are observable by the other aircrew members Increased rate and depth of breathing /Cyanosis /Mental confusion / Poor judgment / Loss of muscle coordination Unconsciousness / Slouching

30

Symptoms of Hyperventilation

similar to those of hypoxia: Tingling sensations /Muscle spasms /Hot and cold sensations / Visual impairment / Dizziness / Unconsciousness

31

Differentiate between hyperventilation and hypoxia

Altitude: Above 10,000 ft, assume hypoxia: Below 10,000 ft, assume hyperventilation Symptoms: Cyanosis only seen with Hypoxia Muscle Spasms only seen with Hyperventilation

32

What is the treatment of hyperventilation / hypoxia.

Treatment Above 10,000 feet- assume hypoxia and treat accordingly. 100% O2 / Descend to a safe altitude. Below 10,000 feet- assume hyperventilation and treat accordingly. Voluntary reduction in rate and depth of respiration is necessary to accomplish this task./ Reading or repeating a checklist in most cases can treat hyperventilation.

33

Your co-pilot has pain in one tooth, what is it and what do you do?

Land and seek dental care. it is Barodontalgia (trapped gas disorders of the teeth).

34

What is the treatment for sinus trapped gas dysbarism?

Stop descent of aircraft and attempt to clear by valsalva

35

A mixture of gases that surrounds the Earth's surface is the __________.

atmosphere

36

The ___________ is the domain of weather, winds, turbulence and convection.

troposphere

37

The physiological zones of the atmosphere are __________,  _________ and __________ zones.

efficient, deficient, space equivalent

38

Oxygen makes up ________ % of gas in the atmosphere.

21

39

_________ is the fluid part of the blood composed mainly of salt, water and proteins.

Plasma

40

________ transport approximately _______ % of all O2 in the body.

Red blood cells, 98,5

41

_________ is a process by which a living organism exchanges gases with its environment.

respiration

42

Respiration is an __________ process that occurs in two phases, the __________ phase and the _________ phase.

involuntary

inhalation/active

exhalation/passive

43

What is the mnemonic for the stages of hypoxia?

ICDC

44

________ hypoxia results when there is interference with the use of O2 by body tissue.

Histotoxic

45

True of false: Hypoxia can occur at any altitude.

True!

46

__________ is an excessive rate and depth of respiration leading to abnormal loss of O2.

Hyperventilation

47

The __________ stage of hypoxia is associated with altitudes of 10,000 - 15,000 feet.

compensatory