Ch 4 Atmosphere & Respiration

Question 1

What are all 6 gas laws?

Answer 1

Boyles law (volume inversely proportional to pressure)
Charles’ Law (Volume is directly proportional to temperature)
Gay Lussac’s law (pressure is proportional to temp)
Dalton’s Law (law of partial pressures)
Henry’s Law (gas mixed in a fluid is proportional to pressure on it)
Fick’s law (law of diffusion)

Question 2

What is the first organ to suffer from the effects of hypoxia?

Answer 2

The brain

Question 3

Hypoxia occurs with reduced levels of atmospheric oxygen. What predispositions will increase someone’s susceptibility?

Answer 3

If they are a smoker
If they’re old
If they are ill or have a lung infection
If they’re overweight or have difficulty breathing already…

Question 4

What is the difference between hypoxic hypoxia and anaemic hypoxia?

Answer 4

Anaemia hypoxia is the body’s inability to carry oxygen around the blood due to lack of haemoglobin.

Question 5

There are many symptoms of hypoxic hypoxia, tell me 6

Answer 5

Any of the following:
Skin colour: increased pallor or cyanosis
Confusion/ situational awareness impairment/ impaired judgement
Cough
Fast heart rate, rapid breathing, short breath, wheezing
Excessive sweating and formication (ants under the skin)
Euphoria

Question 6

Which hypoxic symptom is the most dangerous and why?

Answer 6

Euphoria, because the victim is unaware of their jeopardy

Question 7

What are the 4 stages of hypoxic hypoxia?

Answer 7

Indifferent (0-10,000ft) slight visual effect and night vision effected from as low as 5000ft.
Compensatory (10-15000ft) symptoms felt. Faster breath and pulse to compensate low O2. Fatigue, irritation and headache.
Disturbance (15-20,000 ft) severe headache, dizziness, euphoria and personality alterations similar to drunkenness. Loss of acuity in vision, ability to recognise danger, muscle coordination and cognitive struggle
Critical/ Acute (20,000ft) complete mental and physical incapacitation and loss of consciousness.

Question 8

How can you treat hypoxic hypoxia?

Answer 8

Provide oxygen and descend to a safe altitude immediately.

Asthma inhaler may help to speed up recovery

Question 9

At 30,000ft in an unpressurised cabin, how long will a victim have before they succumb to hypoxia?

Answer 9

1-2 mins (halved if overweight or a smoker)

Question 10

What activities will increase risk of decompression sickness?

Answer 10

Scuba diving, increased activity, alcohol consumption the day before, previous exposure to DCS within 2 days prior

Question 11

What is the total capacity of the lung? (On avg.)

Answer 11

6000ml

Question 12

What percentage of the total lung capacity is exhaled normally?

Answer 12

80%

Question 13

What causes hyperventilation?

Answer 13

Anxiety/ stress
Motion sickness
Deliberate inducement

Question 14

If you cannot tell whether a passenger is suffering for hypoxia or hyperventilation, which do you treat them for?

Answer 14

Hypoxia ALWAYS

Question 15

How do you treat hyperventilation?

Answer 15

Old school paper bag

Question 16

What is the average inspiratory capacity?

Answer 16

3600ml

Question 17

What is the term used to describe the volume of air inhaled and exhaled with each normal breath?

Answer 17

Tidal volume 🌊

Question 18

the atmosphere is mostly made up of what gas?

Answer 18

Nitrogen 71% and Oxygen 21%

Question 19

What is the temperature of the isotherm contained within the stratosphere?

Answer 19

-56.5 degrees C

Question 20

What is the lapse rate for temperature within the troposphere?

Answer 20

1.98/ 2 degrees per 1000ft

Question 21

In which layer of the atmosphere will you find the ozone layer?

Answer 21

Stratosphere

Question 22

What effect does the ozone layer have on the atmosphere in terms of temperature?

Answer 22

It warms up the air below and plays a role in the isotherm conditions of the air below it in the stratosphere

Question 23

What is absolute humidity?

Answer 23

the weight of water vapour present in a unit volume of air (g/m3) at a given temp

Question 24

How would you calculate the relative humidity?

Answer 24

Actual humidity / max humidity - given as a percentage

Question 25

IF at 36,000ft how much LESS than the ISA would the atmospheric pressure be ?

Answer 25

1/4

1/2 reduction if at 18,000 ft and 3/4 reduction if at 8000 ft

Question 26

To what degree does the pressure of water vapour in the lungs vary with altitude?

Answer 26

Trick question! Water vapour is ALWAYS at 47 mmHg

Question 27

55mmHg is the minimum partial pressure required in the alveoli for the lungs to function. At what altitude might you experience this?

Answer 27

12,000ft

Question 28

What is the name of the protein in the blood that absorbs oxygen?

Answer 28

Haemoglobin

Question 29

At MSL what is the Total pressure?

Answer 29

160 mmHg

Question 30

The pressure inside the lungs is slightly more than atmospheric pressure. True or false?

Answer 30

False! See p64 for further info

Question 31

In most commercial airline a/c, the cabin is set to what altitude?

Answer 31

8000ft

Question 32

What role does the nose play in respiration?

Answer 32

The air first visits the nose when breathing and then moistens the air and warms it up to increase the efficiency of gas exchange.

Question 33

What are the tiny blood vessels called that wrap themselves around the alveoli?

Answer 33

Capillaries

Question 34

Where does internal respiration take place?

Answer 34

At a cellular level. It provides oxygen and glucose to the muscles. This is also known as metabolism;

Question 35

What are the waste products association with internal respiration?

Answer 35

Water and carbonic acid. The latter of these controls our breathing rate.

Question 36

what is the average external respiration rate?

Answer 36

12-20 breaths per min

Question 37

The more acidity in the blood, the faster we breathe. True or false?

Answer 37

True! Carbonic acid controls our breathing rate and so the more acid in the blood, the faster we breathe.