Lecture 20 (Exam IV) Flashcards
(80 cards)
1
Q
- What is the highest altitude location on earth?
- How how up is it?
A
- The summit of mount everest
- 9km
2
Q
- What is the atmospheric pressure at the summit of mount everest?
- What would be the partial pressure of inspired air here?
A
- 253mmHg
- 43.1mmHg
3
Q
How long could most humans sustain life with a PIO2 of 43.1mmHg?
A
Just under a few hours
4
Q
What is the purpose of the base camps along the way up the mountain of mount Everest?
A
So hikers can let their lungs adjust to the lower atmospheric pressures.
5
Q
Wshat is a short term compensatory mechanism your body does when you ascend up a mountain and are exposed to higher altitudes?
A
- hyperventilate
- Ventilation will come back down to normal levels after a few days of being exposed to higher altitudes
6
Q
What is a long term compensatory adjustment your body makes when exposed to higher altitudes?
A
- If we have a low PaO2 in our blood, that will equate to less oxygen being delivered to the kidneys
- The kidney sensors will detect a low PaO2 and release epo
- The epo will expand the hematocrit to help out with oxygen delivery
7
Q
Where are your kidney sensors for detecting a low PaO2 located?
A
In the inner medulla (super deep parts of the kidney)
8
Q
What are the kidney sensors in control of?
A
How much epo we produce
9
Q
What lab value will be high if you are up in the mountains/high elevation for a few days?
A
Hematocrit as a result of the actions of epo
10
Q
People who were born at higher altitudes have more ___ in their lungs than people who were born at lower altitudes
A
alveoli
11
Q
What does being born with more alveoli do for the people who were born and grew up in places of higher altitude?
A
It gives them significantly more surface area available for gas exchange which is needed since there is less atmospheric pressure (less oxygen gets inspired)
12
Q
People who were born in high altitude areas and have more surface area in the lungs for gas exchange are better at what sport?
A
Running marathons at lower altitudes or sea level due to their enhanced lungs.
13
Q
- What are the 2 limiting factors to our performance for everyday activity like playing sports?
- What is not a limiting factor?
A
- The heart and cardiac output
- Lungs are not a limiting factor
14
Q
Typically we have about ___ times the amount of lung area than we really need over the course of our life.
A
3 times
15
Q
True or false
Damage to the lungs from smoking comes from short term use
A
- False
- You won’t see many effects from short term use. Damage to the lungs comes from long term/many years of smoking.
16
Q
Is having altitude sickness genetic or acquired?
A
Genetic and we don’t know who will be predisposed to it. You either have it or you dont.
17
Q
Why do airplanes fly at such high altitudes?
A
- Because the higher up in altitude the thinner the air.
The thinner the air, the better the gas mileage the plane gets.
18
Q
The pressurized cabin in an airplane mimics an ___ ft environmental condition
A
8000ft
19
Q
If we are at 40,000ft in the air in an airplaine, the atmospheric pressure at this height is ___ and the PO2 is ___.
A
- 140mmHg
- 29mmHg
20
Q
Why dont they pressurize the airplane cabin to mimic the conditions at sea level?
A
- Because it would require them to push a whole lot more pressure into a small space.
- More pressure = more danger, more explosive
21
Q
A
22
Q
At high altitudes, what is one major thing you will see in your lungs as a response to the lower partial pressure of inspired oxygen?
A
HPV
23
Q
How do the masks work when an airplane suddenly becomes depressurized?
A
- The masks are connected to a metal container in the plane that has a bunch of chemicals in it.
- When you tug on the mask and put it on, it sets off a chemical reaction in the metal container that ends up producing oxygen for you to breathe.
- Its not a lot of oxygen, but it is more than what the atmospheric pressure will be, and its enough to keep you alive until the plane gets down to a lower altitude.
24
Q
What happens to your lungs if the plane suddenly depressurizes and you don’t put the oxygen mask on?
A
- You end up breathing in oxygen at an inspired partial pressure of 29mmHg.
- The 29mmHg is even lower than your capillary blood PO2 and it creates a negative delta pressure.
- This causes gas exchange to happen in reverse since the capillary PO2 is higher than the alveolar PO2, and the oxygen in your blood will move from the capillaries to the alveoli
- This reversal physically strips the oxygen off the hemoglobin in the blood and pushes it into the alveoli
- This will lead to rapid unconsciousness and death.
25
What kind of oxygen device do the pilots get if the cabin becomes depressurized?
* A source of compressed 100% oxygen that comes in a little bottle, with a mask that tightly fits on their face.
26
What chemical reaction takes place in the little metal boxes to produce oxygen for the passengers on the plane?
exothermic
If one of these gets set off when it is supposed to, it could start a fire or explosion on the plane.
27
What is the lowest atmospheric pressure on land below sea level?
death valley
28
Why is the concept of lower altitude and higher atmospheric pressure magnified if you are descending into a body of water?
Because water is heavier than air and it adds more pressure
29
If you deep dive down to 500ft in the ocean, you will be at ___ ATMs and have an atmospheric pressure of ___.
* 16ATMs
* 12160mmHg
30
If you are going to subject your body to really high atmospheric pressures when you go diving in the ocean, what is required to help you lungs?
a high pressure scuba tank
31
* At an atmospheric pressure of 5000mmHg, what the oxygen partial pressure in your body be?
* What will the nitrogen partial pressure be?
* O2 = 1044mmHg
* N2 = 3956
32
When scuba diving, what is the gas we are most worried about?
Nitrogen
33
* What is in a standard scuba tank?
* What are the benefits of using this kind?
* It is packed with atmospheric gas with an air compressor. It has normal atmospheric concentrations, little to no CO2, N2 of 79%, and O2 of 21%
* It is cheap and you don't have to deal with the risk of explosion because it doesn't contain 100% O2.
34
Is nitrogen soluble or insoluble?
Very insoluble
35
What happens to inspired nitrogen from a scuba tank when you dive down really deep in the ocean?
Even though nitrogen is insoluble, at very deep atmospheric pressures, it will eventually get pushed into your blood.
36
What is the biggest concern with nitrogen getting pushed into your blood when scuba diving and then surfacing to quickly?
You will get nitrogen toxicity
37
How do the pressures of gases adjust when you surface from scuba diving?
The gases come out of the solution (your blood)
38
What is nitrogen toxicity?
* When we surface to quickley and the nitrogen comes out of your blood but then goes other places in your body.
* The nitrogen forms air emboli in your circulatory system, which will be lethal
39
How does a scuba diver prevent the sudden transition of dissolved gas (nitrogen) in their blood from turning back into a gas form and creating air emboli in their circulatory system?
They ascend to the surface very gradually so their body can adjust to the pressure changes.
40
Where does a scuba diver need to go if they ascend to the surface too quickley?
a hyperbaric chamber
41
* What can happen to your blood if your ascend to the surface to quickley when scuba diving?
* How does this happen?
* What kitchen mechanism does this equate to?
* Your blood can boil
* This is due to the nitrogen going from liquid back to gas in a rapid decompression scenario.
* This is similar to boiling a pot of water on the stove.
42
What movie was mentioned in class when talkin about nitrogen toxicity?
total recall
43
What will an oxygen tank with 100% oxygen at a high pressure cause?
* oxygen toxicity
* These tanks are more expensive and more explosive
44
A standard hyperbaric chamber can simulate an environment ___ times that of normal sea level.
3 times that of normal sea level pressure
45
List the uses for a hyperbaric chamber. (4)
* treatment of rapid decompression from surfacing too quickley when scuba diving
* Used in hospitals to treat wound healing for diabetics, or patients with compromised immune and CV systems.
* Used on oil rigs in the gulf because some of the workers have to dive to work on equipment on the rig.
* The military uses them too
46
What celebrity had a personal hyperbaric chamber?
michael jackson
47
Because oxygen is relatively insoluble in blood, how does it get around?
It hitches a ride on hemoglobin because that is where it is most comfortable.
48
* How do we increase the amount of oxygen in blood, more than what hemoglobin can carry?
* Any of the added oxygen has to be in the ___ form.
* The only way we can do this is to increase the alveolar PAO2 with a higher than normal FiO2 (21%)
* You could also put someone in a hyperbaric chamber and give more environmental pressure to the existing oxygen in the chamber
* Dissolved
49
* What is the FiO2 we usually gives patients in the OR when they are on the vent?
* What does this help offset?
* 30%
* A little bit higher than normal FiO2 in the OR helps offset all of the things we are doing that are messing with the lungs normal physiology. EX: anesthetics, lower lung volumes, no compensatory responses, etc.
50
* What are the 4 dangerous oxygen molecules?
* Why are they dangerous?
* O2- = superoxide
* OONO- = peroxynitrite
* H2O2 = hydrogen peroxide
* NO = nitric oxide
* Because they are really reactive
51
Derscribe O2-
* Superoxide
* An O2 molecule that has an extra electron added to it.
* The extra electron is unpaired and very reactive
* Superoxide will degrade a bunch of different compounds
52
Describe OONO-
* Peroxynitrite
* This is a combination of superoxide and nitric oxide together.
* This is only formed if you have large amounts of both O2- and NO.
* This interacts with and mutates DNA
* Will mess up cells long term and cause cancer
53
Describe H2O2
* Hydrogen peroxide
* Smaller less dangerous compound
* A reactive specied used in aseptic substances cfor wounds
54
Describe NO
* Nitric oxide
* In small amounts is good for relaxing blood vessels
* Can be toxic if we have it in excess because it will react with other compounds to create dangerous substances like peroxynitrite
55
True or false:
Our body uses dangerous oxygen molecules in small amounts all the time
* true
* They are typically in very specific places in the in the body like macrophages or killer immune cells.
* They are generated in very small amounts from the macrophages and killer immune cells to degrade bad things.
56
What is another name for dangerous oxygen molecules?
Reactive oxygen species
ROS
57
What enzymes in the body help regulate our reactive oxygen species?
* Superoxide dismutase
* Peroxidases
* Catalase
* Acetylcysteine
58
* What is N-acetylcysteine often used for?
* How does it work?
* Overdose of acetaminophen (tylenol) to protect tvhe liver against damage
* It overwhelms the livers ability to degrade the toxins that result from tylenol overdose
59
True or false:
You can buy N-acetylcysteine over the counter
True but the government is trying to make it prescription only
60
* Who was the last iron lung living patient?
* What hospital did he live at?
* When did he die?
* What kind of degree did he get while in the iron lung?
* Paul alexander
* Parkland in Dallas
* Last year
* Law degree
61
What is the iron lung used for?
The treatment of chronic respiratory failure, particularly Polio
62
What decade did the polio oitbreak occur?
the 1960's
63
With the iron lung, you have ___ ___ to the lungs and airway than you would with positive pressure ventialtion
less trauma
64
What does the polio virus do?
Derstroys the ability of the nervous system to communicate with skeletal muscles, which are needed for normal breathing.
65
How does the iron lung work?
* It is a big cylinder with a cap on the end and then a rubber/leather diaphragm that they put around the patients upper body or neck. This helps create a pressure seal between the inside of the tank and the outside of the environment.
* when the patient needs to inspire, there is a pulley that pulls out the cap at the end of the tank. This pulls the diaphragm out which creates negative pressure and allows the patient to draw in air.
* When the diaphragm on the iron lung pulsl out, the pressure inside the container is reduced, which then draws air into the patients lungs.
66
Besides th iron lung, what is another way we can put air into a patient?
By pushing it in through psotive pressure ventilation with the anesthesia machine.
67
What is the downside of using PPV versus the iron lung?
PPV causes more damage to the lungs and airways and you don't live as long.
68
The iron lung was designed to mimic what kind of breathing?
Normal negative pressure ventilation/breathing.
69
* Negative pressure ventilation =
* Positive pressure ventilation =
* drawing air into the lungs
* pushing/forcing air into the lungs
70
What actor was on PPV with a trach and died from lung complications?
Christopher Reeves
71
What are the advantages of PPV vesus the iron lung?
It allows you to be moble
72
With negative pressure ventilation, which alveoli get filled first?
* The alveoli that are closest to the superficial borders of the lung tissue fill first because they are the closest to the negative pleural pressure that is pulling on the lung.
* Specifically the deeper alveoli towards the base of the lung get filled first because when we inspire those get stretched open the most.
73
With positive pressure ventilation, which alveoli get filled first?
* When we force air onto the lungs with PPV, the alveoli that are closest to the larger airways get filled first. This works from filling the inner to outer kind of direction.
74
When was the polio vaccine developed?
The 1960's
75
What was the initial treatment for polio before the vaccine was developed?
the iron lung
76
What significant event happened with one of the polio vaccine trials?
* One batch got screwed up and they accidentally injected 10,000 people with the live polio virus.
* Most of these people ended up in the iron lung.
77
* What population was affected by polio the most?
* How did they contract it?
* Children
* It was a virus found in public swimming pools
78
True or false:
Polio has pretty much been eliminated since the release of the vaccine
* True
* With the exception of 3rd world countries that don't get vaccinated
79
79
What charity was initially founded to fund the research of polio?
The march of dimes
