sphyrnidus
Contributor
Suits me, but still a long way from 100%...
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When i said before that:But this statement is about 100% Oxygen. Recreational mixtures do not exceed 36%.
I calculate that based on air (21%)If this law is correct then it can be 6 times more.I know is not much if you compare it with the oxygen on hemoglobin but is still almost 1/10th of the total.
There is actually very little oxygen dissolved in the blood. Yes it's the oxyhemoglobin that does the trick.
And yes I doc
Thank you for your time but i still disagree.I really learn a lot by this thread and hope my understanding gets more clear.Maybe iam not doing correct my maths.For the last example of being able to dissolve enough oxygen to be effective at 3 ATM and at 100% oxygen for hyperbaric therapy may be true under those circumstances. Your equations are correct. But, divers do not dive at 100% oxygen. They dive at no more than 36%-40% oxygen. We are also stipulating that the OP is diving at depths above 65 Ft at the deepest. At 3 ATM you are closer to 100 ft., a depth that is greater that what we are experiencing. You are invoking variables that don't pertain to the actual situation we are discussing.
You are trying to deliver a coffee cup of heat but that is not the same as a bath tub of heat. If that makes sense.
copy-paste:The other oxygen that is dissolved in the blood is just, well, O2 dissolved into a liquid. That O2 that is not attached to the hemoglobin is not used by the body to, for example, feed the heart. That is why it's not significant.
If we take the person to 40% FI02 and down to 4 ATA, that's about 8 times as much dissolved oxygen, or 2.4 ml/dl, which brings the contribution up to 10% of the total oxygen. It's a 12% increase in total available O2. It just isn't going to make a difference. As I mentioned earlier, research shows that normal people (not conditioned athletes) even when exerting do not drop their arterial saturation, which says that the diffusion across the alveolar membranes is fast enough to supply the oxygen requirements of the tissues. Perhaps for an extremely conditioned individual under maximal stress, the extra 12% might make a difference, but for the average diver, it simply isn't going to change anything.
Blood: Plasma and Red Blood Cells
For purposes of discussing oxygen transport by the blood, we will consider blood to be composed of two phases: plasma and red blood cells (RBCs). The fractional volume of blood occupied by RBCs is called the hematocrit, and its value is a little less than 50% in human adults (∼40% for females and ∼45% for males). Oxygen is carried in the blood in two forms: (1) dissolved in plasma and RBC water (about 2% of the total) and (2) reversibly bound to hemoglobin (about 98% of the total).
At physiological PO2 (40 < PO2 < 100 mm Hg), only a small amount of oxygen is dissolved in plasma since oxygen has such a low solubility. At elevated PO2 (breathing 100 % oxygen or during hyperbaric oxygenation), however, the physically dissolved form of oxygen can become significant. Henry's law states that the amount of oxygen dissolved in plasma is directly proportional to PO2...
2. Following its entrance into the blood, a certain amount of
oxygen is immediately combined with hemoglobin in the
blood. If the patient is breathing air at sea level most of the
oxygen in the blood is combined with hemoglobin. A very
small amount is dissolved in the plasma.
a. The amount of oxygen carried by hemoglobin
depends on the amount of hemoglobin in the blood.
In general, 100 ml (3.33oz) of blood carries
approximately 20.4 ml of oxygen. Once hemoglobin
is saturated with oxygen, it provides no additional
oxygen for the tissues under hyperbaric conditions.
b. A very small amount of oxygen, not combined with
hemoglobin, is dissolved in the plasma when a patient
breaths air at sea level (1 ATA). Approximately 100 ml
(3.33 oz.) of blood has only 0.31 ml of oxygen in it
at sea level.
Under hyperbaric conditions more oxygen is available
to be dissolved in the plasma governed by Henrys
Law. For each 100 mmHg increase in the oxygen
pressure in the alveolus another 0.31 ml of oxygen
can be dissolved in the plasma. We can increase the
dissolved oxygen up to 15 times normal by the use of
hyperbaric therapy.