Respiratory System

Question 1

What is internal respiration

Answer 1

Exchange of gas in the lungs and body tissues.

diffusion of oxygen from lung into the blood
and CO2 from blood to lungs

diffusion of oxygen from blood into into the cells
and CO2 from cells to blood

Question 2

what is External respiration

Answer 2

process of inhaling air and transporting oxygen from nose or mouth to the lungs till oxygen is defused in the blood stream. And vice versa, where we expel CO2

this function is controlled by the prephiral system - the autonomic nervous system - because it’s done unconsciously

however we constant control the depth and rate of our breathing

Question 3

Explain inhilation process

Answer 3

1.Air enters mouth or nose
2.Air passes through pharynx (tube between nose and larynx) and then to larynx (voice box)
3.Air passes to Trachea (semi-regid tube built with cartilage rings).
4.Trachea branches into 2 bronchi servicing each lung
5.Particles in the air get caught here the mucus lined walls of bronchi and trachea then slowly back up the mouth
6.Bronchi split into 2 again and again
7.As air passes through, it gets moist and warm
8.Bronchi eventually end at the Avleoli. Its walls are coated with fine layer of moisture
9.Alveoli are small spherical bags grouped in Alveoli sacs.
10.Membrane of the alveoli are thin and surrounded by capillaries
11.The pressure of oxygen in the air helps with the oxygen diffusion into the blood
12.The oxygen molecules entering each alveolus dissolve into liquid and through its members and into the capillaries, into the blood plasma
13.O2 molecules bind to the haemoglobin in the red blood cells
14.oxygenated blood passes to the left side of the heart, which then pumps it out into the body via arteries.

Question 4

Explain Expiration

Answer 4

1.Simultaneously, deoxygenated blood travels to the right side of the heart
2.Pumps it back into the alveoli
3.In the Alveoli sac, CO2 molecules in the blood diffuse across the membrane into the alveoli from where they are expelled from the body via breathing out. Some of this process also happens at the final stages of bronchi

Question 5

How much oxygen does the brain take

Answer 5

(even though our brain makes up 2% of our body weight) our brain consumes 20% of the oxygen we take in

Question 6

how many alveolis are in normal human

Answer 6

300,000 alveolis exist in the body - this makes up 80m2 of gas exchange area

Question 7

during hard excercise, how fast does blood pass from alveoli to capillaries

Answer 7

To keep the body oxyginated during excercise, it take 0.3 seconds for blood to pass from alveoli to capillaries

Question 8

how many inhilations/exhilations are made per min and what does this equate in heart beats per min

Answer 8

15 inhilations & exhilations per min
= 70 heart beats/min

Question 9

Relationship between Oxygen and Carbon Dioxide

Answer 9

1. Body stores more CO2 than O2 hence why the body needs sufficient levels of O2
2. CO2 helps body regulate O2
3. CO2 helps maintain chemical balance in the body
4. Breathing rate is affected by CO2 but also stress, anxiety, illness or injury

• O2 saturation levels in the blood is usually held at 98%. It drops below 90% when the Partial Pressure drops to 60mmHG
• Might seem when take in a lot of oxygen when we exercise but oxygen levels in the blood are held at tight limits

Question 10

External mechanism to assist the lungs in external respiration

Answer 10

Brochi don’t have the ability to support themselves, therefore the lungs cannot inflat themselves. Infact, lungs can collapse if pressure in lungs is lower than that of the chest cavity

therefore, external mechanism is required that relies on:

Pleural cavity
Thorax
Diaphragm
InterCostal muscle

Question 11

What is pleural cavity

Answer 11

The lungs are protected by the pleural membrane

The space between the lungs and the pleural memberane is the pleural cavity

Question 12

What is thorax

Answer 12

Lungs and heart are located in the Thorax (chest cavity)

The thorax also has airtight membrane

the thorax is seprated from lower abdominal cavity by the diaphragm

Question 13

What is the diaphragm

Answer 13

a muscle that separates thorax from abdominal cavity.

it flattens when breathing in, and relaxes into cone shape when breathing out.

Question 14

Explain what happens when breathing in

Answer 14

Breathing in causes the diaphragm to flatten because the volume of ai in the lungs expands.

Here the pressure in the pleural cavity is lower
compared to the pressure in the lungs

Question 15

What happens when breathing out

Answer 15

Breathing out causes the diaphragm to relax and go back to its cone shape.

the volume of air in the lungs reduces.

Here the pressure in the pleural cavity is higher
compared to the pressure in the lungs

the compressed lungs expel CO2

Question 16

What is the muscle that helps the Diaphragm

Answer 16

During intense excercise, the body needs a lot of oxygen and to the support the speed of inhalation and exhilation, the diaphragm needs the

InterCostal Muscle - sits in the ribs and helps expand the ribs to allow the lungs to expand ( more volume) and vice versa

Question 17

What is volutary respiration

Answer 17

When you can consciously control your breathing (holding breath, signing, etc)

Question 18

Involunatry repiration

Answer 18

Occurs in the inenr body (with the brain) and to some degree is automatic

Question 19

How does Carotid arteries assis in involutary respiration

Answer 19

in the coratid artery, there are sensors that monitor the acidity of the blood and the levels of CO2 and O2.

If CO2 are high, these sensors send signals to the brain and the brain sends signals to the Thorax to expand and ‘inhale’ more air

Question 20

Hyperventiation definition

Answer 20

when body is needing to **breath fast and deeply **more oxygen more than the usual
feeling breathlesness even though you are breathing more oxygen

Question 21

What is happening physiologically during hyperventilation

Answer 21

Overbreathing causes excessive flushing out of CO2 from the body.

The carotid artery recognizes that the carbonic acid is reduced and thus sends signals to the nervous system, and this signal constricts the blood vessels …..hence reduced blood flow to the brain

Question 22

What causes hyperventilation

Answer 22

Anxiety & stress

Movements such as: turbulence, vibration, g force, motion sickness

Stroke & brain injury

Voluntary hyperventilation

Question 23

What are symptoms of hyperventilation

Answer 23

dizziness, headache, light headed

Tingly lips, hands and feet
hot and cold flushes
impaired performance
imparied vision
unconsciousness / fainting

Question 24

how to resolve hyperventilation

Answer 24

control breathing voluntarily or
breath into a paper bag to re-breath CO2

The more CO2 brought back to the body, the more the oxygen levels are balanced, and blood flow is unrestricted to the brain.

Question 25

what is a panic attack

Answer 25

usually caused by stress and anxiety and when the sympathetic nervous system releases adrenaline, hyperventilation can be triggered.

Question 26

Hypoxia definition

Answer 26

In high Cabin altitude: As you fly up in altitude, air pressure and density decrease,: - the mass of oxygen taken into the lungs decreases - partial pressure of oxygen decreases - less oxygen diffuse acrosse the alveoli - less energy generated for cells and brain the amount of oxygen available isn't sufficient to meet the body's needs (primiarly to meet the brain's needs)

Question 27

4 types of hypoxia

Answer 27

Hypoxic Hypoxia Aenemic Hypoxia Stagnant Hypoxia Histotoxic Hypoxia

Question 28

Hypoxic Hypoxia

Answer 28

When body is not getting sufficient oxygen **to the lungs** themselves (oxygen diffusions at blood level assumed to be working fine) Due to lung infection, blocked airways, drug overdose Due to drop in oxygen partial pressure at altitudes esp 10,000 ft AMSL and above where the body struggles to taken in enough oxygen

Question 29

Aenimic Hypoxia

Answer 29

When body is not getting sufficient oxygen **at blood level** This asssumes there is sufficient oxygen from the environment is coming through to the lungs, but not sufficient oxygen is transported to the blood. aenimic, heamoglobin difficiencies, Asthma, carbon dioxide poisoning

Question 30

Histotoxic hypoxia

Answer 30

caused by poisning in blood stream - such in the case of carbon monoxide poisoning

Question 31

Stagnant hypoxia

Answer 31

Caused by reduced blood flow to the brain due to clogged arteries & vessels - caused by heart conditions

Question 32

explain how carbon monoxide poisoning can happen

Answer 32

carbon monoxide is a product of combusion of material using carbon (aviation fuel) it's an ordorless and colorless gas when cold air passes into an exhaust system to be warmed, this process produces carbon monoxide. If the pipes have holes in them, the gas can leak into the vents when this gas is breathed into the body, it tends to bind 200x more to the haemoglobin than oxygen, therefore the blood carries more CO2 than O2 to the brain.

Question 33

Symptoms of hypoxia

Answer 33

Subtle sneaks up on you starts with change in personality - feeling euphoric throughout imparied judgement - feeling like you are right but actually not impaired decision making, confusion impaired coordination dizzy, drowsy, headache impaired vision - color vision, night, bluriness cyanosis - blue lips, hands and feet Tingly hands and feet slurred speech loss of memory irritability stomach gas ear discomfort hyperventilation unconsciousness/fainting/death **some of these symptoms are more noticeable at 10,000ft +)**

Question 34

Other factors that affect the threshold of hypoxia (ie. can reduce time of usefull consciousness)

Answer 34

The effects of oxygen depreviation is different from one person to another - deterioration happens at different cabin altitudue for each person..but 10K ft is critical pressurized cabins if they are depressurized alcohol, drugs, smoking stress and anxiety fatigue or workload illness/cold Time in altitude Excercise

Question 35

What is time of usefull consciousness

Answer 35

time left that pilot is consciously aware during hypoxia (ie without supplementary oxygen) - this time reduces as altitude increases: 20,000 ft = 30 min 22,000 ft = 5 - 10 min 25,000 ft = 1 min - 180 sec 30,000 ft - 45 - 90 sec 35,000 ft - 30 - 45 sec 40,000 ft - 12 - 15 sec

Question 36

Solutions to apply during hypoxia

Answer 36

reduce altitude to below 10,000 ft check on each other oxygen supplementation oximeter to test level of oxygen in the blood CO2 detector (visual/audible)

Question 37

how to distinguish hypoxia from hypeventilation

Answer 37

Hypoxia symptoms tends to show at 10,000 ft Hypoxia causes cyanosis (blue lips, hands and feet) hyperventilation can be a symptoms of hypoxia, not the other way around.

Question 38

Other issues that can be gas related

Answer 38

1) eating gassy food as gas can expand and cause abdominal pain - barotrauma 2) air trapped in dental fillings - barotrauma 3) air trapped in sinus - respiratory tract infection/barotrauma 4) decompression sickness due to diving. Should not dive 24 hrs prior to flying or 12 hrs if only dived 10m (30 ft). You many notice symptoms of DCS at 6000 ft altitude

Question 39

Carbon monoxide

Answer 39

caused by cigarrette smoke OR product of internal incomplete combustion engines. gas is vented thrug the exhaust pipe of of a piston engine

Question 40

Piston exhaust gas

Answer 40

contains 9% CO usually engine and exhaust pip are close to the cabin can be used as a heat source to warm the cabin but if it's damaged, exhaust gas can enter the cabin

Question 41

eHypoxia causs cyanosis but not in the case of CO poisoning...

Answer 41

No cyanosis Here the skin is flush and rosy

Question 42

Carbon monoxide is cumulative

Answer 42

0.5% is removed per 4 hours meaning if you fly in low CO over time, you can still contaminate your blood

Question 43

if CO is detected in cabin

Answer 43

turn off all cabin heating open all air vents use 100% oxygen (not mixed air) or used oxygen supplement land Prevent: fresh air, regular maintenance

Question 44

why does the body need oxygen frequently

Answer 44

because the body can't store oxygen

Question 45

what is external respiration called

Answer 45

ventilation

Question 46

what is a respiratory system

Answer 46

respiration brings energy-given O2 to the body so it can absorb it and removed CO2 that it expels The use of oxygen in each cell and creating energy by using oxidation (oxidizing fuel)

Question 47

function of resporatory system

Answer 47

gas exchange between outside environment and circulatory system immune defence to help fight infection entering from the lung talking release of chemicals, proteins, enzymes to control other body systems

Question 48

cellular respiration

Answer 48

occurs inside cells where oxygen is used in a biochemical pathways to produce energy

Question 49

Breathing rate

Answer 49

Ventilation rate the autonomic nervous system senses - the need for more blood in the body - amount of CO2 in the blood a higher than normal amount of CO2 means a lot of oxygen has been burned and need for more as a result of high carbon dioxide in the blood, the breathing rate is automatially increased to bring more oxygen into thelungs for the blood stream to absorb

Question 50

capacity of lung

Answer 50

can take up to 5 litres of air at rest, one breath is 1/2 a litre

Question 51

content of the lung

Answer 51

there is always some air in the lungs that contains higher concentration of CO2 than the atmoshphere and lower concentration of O2. also saturated with water vapor

Question 52

Symptoms of CO2 poisoning

Answer 52

headache, dizzy,nausea imparied vision imparied motor skills, decision making or judgement imparied memory, change of personality slow breathing convulsion coma, death

Question 53

upper respiratory tract infection

Answer 53

when the upper tract like nose, mouth, sinuses are affected due to an infection or a cold, and disable you from equalizing your ear pressure

Question 54

partial pressure

Answer 54

when altitude is gained, air thins out with fewer molecules in the same volume but % of compositions doesn't change

Question 55

Boyl's , charles, Henry, dalton laws

Answer 55

Boyles if Temp is constant, Pressure decreases then volume increases Charles, If pressures is constant, temperature increases, voume increases Dalton, the total pressure is the sume of its partial pressure Henry, Decomposition sickness