ALERT!!! Nerdy sciency post.
Imagine giving 240%-280% oxygen. Possible? Yes of course, but only in a hyperbaric chamber. Lets review what you understand of 100% oxygen.
Right now, if you are sitting at sea level in and you place a tight fitting bag-valve-mask on your face and run it at 15lpm; you will be giving yourself 100% oxygen.
That means- 100% oxygen at 760mmHg. (Seal level or atmospheric pressure).
Atmospheric pressure =1 Atm = 760mmHg.
Our atmosphere is made up of gases. Mostly nitrogen 78% and oxygen 21% and a 1% mix of other gases.
Breathing air we are breathing is therefore 21% of 760mmHg
Meaning O2 pressure on room air is 159mmHg (0.21x760=159)
When you're breathing 50% O2 then this is the same as saying you are breathing 50% of 760mmHg = 380mmHg Oxygen pressure.
100% of 1 atmosphere (760) is the same as PO2 = 760mmHg.
....
Now... The highest concentration of a gas is 100%, but what if you could breath that same gas at higher atmospheric pressure? Well this is the principle of Hyperbaric Oxygen Therapy (HBOT).
Typically in a HBOT chamber a patient breathes 100% at higher than 760mmHg (1atm).
Common examples are diabetic and other chronic would patients, or those with radio necrosis, who are treated at 14 metres of seawater (msw).
And... Divers with bends, or carbon monoxide poisoning, and gangrene infections who are treated at 18msw.
No!!! They don't wear togs, and they don't get wet. The term msw means that they are subjected to the equivalent pressure in a chamber, as a person diving at a depth of 14 or 18 msw.
The deeper you dive under water, the greater the pressure.
For every 10 msw the atmospheric pressure doubles our atmosphere.
Sea level = 760mmHg (1 atm)
10msw = 1520mmHg (2 atm)
14msw = 1824mmHg*
18msw = 2128mmHg*
20msw = 2280mmHg (3 atm).
In rare cases of cerebral arterial gas embolism (CAGE) or severest cases of the "Bends" , a patient might be treated at 30msw which is 4 times the pressure on land (3040mmHg).
So, now we do some very simple maths. If 100% O2 at sea level is 760, then the pO2 at 14msw (2.4 atm) would be 1824mmHg or the equivalent of 240% oxygen.
At this pressure (concentration) oxygen changes in its physiological effects. It now dissolves into blood plasma exerting paO2 of 1700-1800mmHg (normal = 80-100)!!
When this high, oxygen is a remarkable antibiotic. It destroys anaerobic bacteria. It also initiates a wound healing process called angioneogenesis.
Angio= blood vessels,
Neo = new
Genesis = creation of
Angioneogenesis is the process of budding new blood vessels into previously avascular tissue, stimulating new cell growth and subsequently, switches on wound healing in previously indolent wounds like venous ulcers, diabetic foot wounds and arterial ulcers.
In divers affected with the bends (nitrogen bubbles in the blood and joints), the effect of pressure literally squeezes these bubbles (shrinking their size), and the high concentration of oxygen helps them off gas their bubbles.
In Carbon monoxide (CO) poisoning, HBOT forces CO off haemoglobin and reduces the half life of CO from 4-6 hours in air, to 23 mins in a HBO chamber.
Does it treat sports injuries... No!
Does it treat MS, CP or Autism? No?
It has been used by quacks and crack pots over 50 years for everything from fertility to longjevity. But reputable HBO treatment facilities are governed by a code of conduct to treat only those conditions for which their is robust RCT research data to support its use.
Fancy a high pressure job? Hyperbaric nursing was a fun departure from any other role, I'd done. And I recommend it for nurses looking for something different, and don't suffer with asthma, or claustrophobia.
With 11 or so reputable chambers in Australia alone, it is worth looking into.
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