Exam 4 - Lecture 2 Flashcards
What is the ATM in space?
0
The highest point on earth is ____ per lecture? (place and meters)
Mt Everest, 9000m or 9km
What is the atmospheric pressure in mmHg and what is the PO2 at the peak of mt everest?
253mmHg; 43mmHg (make sure you include water vapor)
21% FiO2 doesnt really change unless?
We are really close to outerspace (he didnt expand on this, and research tells me its 21% no matter what?)
How long can most humans on the planet tolerate a PO2 of 43mmHg?
A couple hours
How do we compensate for exposure of high altitude, at first?
Hyperventilate, takes a few days to compensate
How do we end up with more HCT a few days after being at a high altitude?
Low PO2 means less oxygen going to kidneys, the inner medulla detects this, produces more EPO and then stimulates bone marrow to to produce more RBC -> increased HCT
How do the lungs change if youre born at a higher altitude?
Significantly more surface area for gas exchange (more alveoli)
This is why ethiopians and kenyans be winnin them damn marathons
What is usually the limiting factor in sports? Why?
Heart, because we typically have 3x the amount of lungs more than needed to keep up with the heart, thats why you can smoke for 3-4 years before seeing negative effects.
Lowest place on earth according to schmidt? (its accurate for the US….)
death valley
A depth of 500 feet underwater will increase our pressure by how much?
16x
Whats the ratio between how many feet of water to 1 ATM increase?
33 feet/10m of water is equivalent to 1 ATM increase
e.g. 33 feet deep is 2 ATM or 1,520mmHg
Whats the barometric pressure at 66 feet or 20 meters underwater?
2,280mmHg or 3 ATM
During descent, the divers are subjected to increasingly high external pressures, and these pressures will __________, and then the gas pressures are applied to the ___________. This is more of a problem with what gas?
compress gas in the lungs; entire body; nitrogen
nitrogen is relatively soluble or insoluble?
insoluble
what is the main concern with deep diving?
Rapidly resurfacing, because we will have extraordinary amounts of nitrogen and when you surface too quickly the nitrogen can form massive air emboli because its trying to escape quickly.
Diving tanks are usually filled with what gas? Why?
just atmospheric because its cheaper and dont have to worry about explosions and shit
Nitrogen is relatively insoluble at surface pressure but?
becomes more soluble at high pressures, dissolving into the blood and tissues.
Whats another reason that divers dont use pure oxygen in tanks?
Pure oxygen at high pressures causes oxygen toxicity
whats the movie that he mentioned in class with nitrogen?
Total recall with arnold schwarzenegger
They were on mars and had a decompression in the space station, showed the skin bubbling, which was nitrogen coming out of solution causing the bubbling.
How can we tell if someone is pre-disposed to altitude sickness?
You dont know, just gone go ahead and figure it out when they die on mt everest cause they try to push through usually!
typically genetic
What camp will people usually figure out that they cant handle the altitude change?
Camp 3!
air emboli can form together and create
a larger embolus; ESPECIALLY DEADLY IN LCA
standard academic hospital hyperbaric chambers can increase the pressure to? Who uses more?
3 ATM or 2,280mmHg
military or professional divers may use more pressure.
What is different about the chambers for oil rigs out in the gulf?
May have physical hyperbaric rooms that divers live in, that way they never have to adjust because theyre in deep depths so often.
How does hyperbaric chamber therapy benefit wound healing?
The chamber can force more oxygen into blood to heal damaged vessels that normally have poor circulation, especially for diabetics who had sticky vessels that the immune system destroyed.
immune system is also exhausted from damaging these vessels so now theyre more prone to infections
Who had a hyperbaric chamber in their house? (along with some other shit… hint hint…..)
Michael “diddler” Jackson
What is the safest way to have increased FiO2 in hyperbaric chambers?
little bubbles around head attached to oxygen hoses. Its cheaper than using oxygen for the whole chamber and safer cause its explosive!
What are the only 2 ways to increase soluble oxygen?
Increased PAO2 through increased FiO2 or hyperbaric chamber (or both)
Any additional oxygen the patient receives from hyperbaric chamber will be in what form?
dissolved in blood.. Hb has a plateau, a max that it can carry, while dissolved oxygen does not plateau on the graph.
What % oxygen will we normally use in OR, and why?
30% cause we are fucking up normal lung physiology (airway reactivity, HPV, surfactant)
What is ROS?
Dangerous oxygen molecules called Reactive Oxygen Species
ROS: O2-
superoxide, has an extra electron and is super reactive.
how is O2- broken down?
Superoxide dismutase
ROS: NO
nitric oxide
Can react with other molecules and create extremely dangerous molecules, such as OONO-
ROS: OONO-
Peroxynitrite
Can destroy DNA, combination of superoxide and nitric oxide, leads to cancer.
ROS: N2O2
hydrogen peroxide
Aseptic substance, body has these in controlled amounts in specific places such as macrophages or immune killer cells, will generate this and insert them into things they want to degrade.
Typical levels of N2O2 are regulated by
Peroxidases, catalase, acetylcysteines
What is N Acetylcysteine S? What special thing did he say about it?
Cuts down on liver damage from tylenol overdose
FDA is trying to make it prescription only, probably because its a supplement that actually fucking works and god forbid we have that on the open market.
Who was the guy in dallas that died recently with the iron lung? how lung was he on it? what degree did he get? What caused his disease? What hospital took care of him?
Paul Alexander, 50 years, Law degree, Polio (google actually says 70 years… but he said 50)
Parkland (representtttt)
What decade did polio outbreak occur?
1960’s (lol again, google says paul got it in 1952..)
Polio: destroys what?
ability of nervous system to communicate with skeletal muscles
How did the iron lung work?
A cylinder with cap on end with rubber/leather diaphragm that they fit around patients upper body/neck to create pressure seal between tank and outside environment.
The pulley pulls the cap which creates a negative environment… Reduces pressure inside container, pulling air into patient.
simulates negative pressure breathing!
Iron lung is better than PPV because its less ____, closer mimics normal body environment of utilizing negative pressure.
trauma
With iron lung, its closer to how body works. It pulls air in in a __________ manner.
very even
Negative pressure breathing:
Alveoli ________________________ will fill first, since thats closest to the negative environment pulling on lung, which will THEN lead to __________________
closest to superficial borders of lung tissue; deeper alveoli stretching and filling as well
Positive pressure breathing:
The inner alveoli expand first (closest to ____), then pushes on the ___________ that expand last (those closest to the _____________).
inner alveoli; closest to large airways; most superficial alveoli; border of the lung
Who was on PPV and did not last 50 years, died of pulmonary issues.
Christopher Reeves
