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Old 8th June 2007, 11:26 PM   #1
Miss Anthrope
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"Man Oozes Green (VULCAN!) Blood"

Whacky article, apparently they think too much of the man's migraine medication turned his blood green.

Quote:
"During insertion, we normally see arterial blood come out. That's how we know we're in the right place. And normally that blood is bright red, as you would expect in an artery," Flexman said in an interview Thursday.
"But in his case, the blood kept coming back as dark green instead of bright red.


"It was sort of a green-black. … Like an avocado skin maybe."


The reaction in the room? "We were very concerned, obviously," said Flexman, who is training in anesthesia at the hospital.
A mild understatement, I'm sure.
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Old 9th June 2007, 01:13 AM   #2
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Cool!

No pointed ears I suppose?


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Old 9th June 2007, 04:55 AM   #3
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Fascinating.
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Old 9th June 2007, 06:58 AM   #4
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Is that story for real?
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Old 9th June 2007, 07:41 AM   #5
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So if the sulfer bound INSTEAD of oxygen, the susequent low oxygen level could have made him sleepy, explaining why he fell asleep in the kneeling position in the first place.
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Old 9th June 2007, 07:53 AM   #6
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I was hoping I could finally learn how to perform the Vulcan Nerve Pinch, only to find out it's just a normal human on migraine medication. Dang!!
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Old 9th June 2007, 08:13 AM   #7
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Just a side-question - would a copper-based blood even be possible? I know iron-based blood works well because of how easily iron oxidizes, but could, in theory, copper-based life exist on a world poor in iron?


Does anyone know the biochemistry involved, and if it's even vaguely feasible?
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Old 9th June 2007, 08:18 AM   #8
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Originally Posted by baskett_case View Post
I was hoping I could finally learn how to perform the Vulcan Nerve Pinch, only to find out it's just a normal human on migraine medication. Dang!!
Yes, but take comfort in knowing that some of the more psychologically challenged Star Trek geeks now know how to take the Vulcan thing one step further.

Geek one: "I had the surgery done on my ears last month. I am SO much more a cooler Vulcan than you."

Geek two wobbles a little uncertainly and pulls out a razor blade: "Yeah, but can you do this?"
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Old 9th June 2007, 08:28 AM   #9
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Originally Posted by Miss Anthrope View Post
Yes, but take comfort in knowing that some of the more psychologically challenged Star Trek geeks now know how to take the Vulcan thing one step further.
You wound me, madam!
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Old 9th June 2007, 10:47 AM   #10
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Originally Posted by Z View Post
Just a side-question - would a copper-based blood even be possible? I know iron-based blood works well because of how easily iron oxidizes, but could, in theory, copper-based life exist on a world poor in iron?


Does anyone know the biochemistry involved, and if it's even vaguely feasible?
Quote:
The medical profession uses an extract from the horseshoe crab's blue, copper-based blood called lysate to test the purity of medicines. Certain properties of the shell have also been used to speed blood clotting and to make absorbable sutures
link
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Old 9th June 2007, 10:55 AM   #11
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The "pigment" itself is called hemocyanin, which means "blue blood".
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Old 9th June 2007, 11:40 AM   #12
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The only naturally occurring terrestrial vertebrates with green blood are five species of lizard found on Papua New Guinea:

Quote:
In 1968 research into the blood of green-blooded skinks determined that the colouration was due to the presence of a biliverdin-type pigment, like that found in bile. Mark has a theory that this may make the lizards taste bitter and deter predators, a once tried, never repeated experience for lizard-eating birds. Dr Chris Austin is the only scientist in the world currently studying green-blooded skinks and he has an alternative theory, one that if correct, might lead to a cure for human diseases like jaundice, or even malaria.
http://www.markoshea.tv/series2/series02-04.html
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Old 9th June 2007, 12:09 PM   #13
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Fascinating!

(time to break out the gaming notes and make some adjustments...)
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Old 9th June 2007, 10:46 PM   #14
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Originally Posted by Z View Post
Just a side-question - would a copper-based blood even be possible? I know iron-based blood works well because of how easily iron oxidizes, but could, in theory, copper-based life exist on a world poor in iron?
The iron in hemoglobin does not get oxidized- the oxygen binds as a ligand, which is why it can so easily come off when it needs to. That's also why carbon monoxide is so toxic- CO is a heckuva good ligand, and will completely displace oxygen from blood and other such complexes.

So copper would work (it does work in horseshoe crabs); theoretically, one could also have nickel, cobalt, manganese, chromium, or vanadium- based protiens that would reversibly bind oxygen. But zinc probably wouldn't work.
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Old 9th June 2007, 11:57 PM   #15
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Originally Posted by Madalch View Post
...So copper would work (it does work in horseshoe crabs); theoretically, one could also have nickel, cobalt, manganese, chromium, or vanadium- based protiens that would reversibly bind oxygen. But zinc probably wouldn't work.
Or magnesium, which IIRC is what plants use; the chlorophyll molecule bears more than a passing resemblance to haemoglobin. And the magnesium in it (IIRC that being it) is what makes plants look green.
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Old 10th June 2007, 09:23 AM   #16
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Originally Posted by baskett_case View Post
I was hoping I could finally learn how to perform the Vulcan Nerve Pinch, only to find out it's just a normal human on migraine medication. Dang!!

Maybe you have it hooked up wrong? Perhaps the Vulcan nerve pinch is just a way to instill a severe migraine?
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Old 10th June 2007, 12:48 PM   #17
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Originally Posted by Gurdur View Post
Or magnesium, which IIRC is what plants use; the chlorophyll molecule bears more than a passing resemblance to haemoglobin. And the magnesium in it (IIRC that being it) is what makes plants look green.
Chlorophyll is indeed a porphyrin complex of magnesium, but I strongly doubt that any form of it would transport oxygen. Oxygen isn't a very good ligand, and magnesium's not a metal that does a lot of non-chelated coordination chemistry. A transition metal (particularly a late one) is more likely to work. If I were designing an alien race, I'd put my money on cobalt.

Now you've got me remembering grade ten, when I put a drop of blood onto a block of magnesium to see if I'd get a single replacement reaction. It didn't turn green.
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Old 10th June 2007, 12:55 PM   #18
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And then there's this:

http://gizmodo.com/gadgets/bloody-he...nes-259627.php
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Old 10th June 2007, 05:41 PM   #19
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Originally Posted by SteveGrenard View Post
Yeah, but does it come in green?
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Old 10th June 2007, 06:09 PM   #20
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Incredible.

Wouldn't blood not bonding to oxygen make you, erhm, die?
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Old 10th June 2007, 06:41 PM   #21
SteveGrenard
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Originally Posted by EeneyMinnieMoe View Post
Incredible.

Wouldn't blood not bonding to oxygen make you, erhm, die?
There are two kinds of oxygen in the body ... bound to hemoglobin and
dissolved. Normally 97% of the blood oxygen is of the bound type so yes would be the answer. However in a hyperbaric chamber you can increase the partial pressure of O2 so high that you can dissolve enough oxygen in the liquid part of the blood making the bound (to hemoglobin) unnecessary.


In the case of plastic blood developers are claiming the following:

Quote:
Just like hemoglobin, the fake blood is made up of plastic molecules that have an iron atom at their core, that can carry oxygen through the body. Dr Lance Twyman claims that the plastic blood, which comes in a water-soluble paste and has a honey-like consistency, is cheap to produce.
http://gizmodo.com/gadgets/bloody-he...nes-259627.php
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Old 11th June 2007, 12:05 AM   #22
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Originally Posted by SteveGrenard View Post
There are two kinds of oxygen in the body ... bound to hemoglobin and
dissolved. Normally 97% of the blood oxygen is of the bound type so yes would be the answer. However in a hyperbaric chamber you can increase the partial pressure of O2 so high that you can dissolve enough oxygen in the liquid part of the blood making the bound (to hemoglobin) unnecessary.

In the case of plastic blood developers are claiming the following:

http://gizmodo.com/gadgets/bloody-he...nes-259627.php

I remember seeing another thread about plastic blood recently. It's not really haemoglobin but the plastic functions similarly in combination with Iron.
The thread can be found here:

I'm not sure where the 97% comes from, but I think you mean that 3% of haemoglobin does not bind oxygen. The 3% is called methaemoglobin which is functionally inactive oxidized haemoglobin in red blood cells, there is also 20mg of the total iron store that is the result of broken down red blood cells and which is taken care of by macrophages. The haemoglobin that gets released when red blood cells are destroyed is bound to proteins called haptoglobins and to be transported to the liver (that's how you get to produce bile). Almost all oxygen in the blood is of the "bound type", it dissociates and is transferred into the tissues and exchanged for CO2...

The transport capacity of your blood depends on the capacity of red blood cells to transport O2, plasma O2, oxygen saturation and the cardiac output (the volume that is pumped round every minute)
The formula is:

DO2= CI x 13.4 x Hb x SaO2

In this equation:
DO2= Oxygen delivery
CI= Cardiac index= Cardiac output / body surface area (Cardiac output= Stroke volume x Heart rate)
13.4= approximate conversion factor (amount of O2/ haemoglobin molecule)
Hb= Haemoglobin concentration in the blood volume
SaO2= Oxygen saturation in the blood

You can also describe it as:

DO2= CO x CaO2 x 10

In this equation
DO2= Oxygen delivery
CO= Cardiac Output
CaO2= arterial Oxygen content in mL/dL (which explains the x10)

CaO2= (Hb x 1.37 x SaO2) + (0.003 x PaO2)
This is a more precise way of calculating.
PaO2= arterial oxygen pressure
0.003= conversion factor for oxygen in plasma

The first part of the CaO2 equation shows the amount of oxygen bound to Hb in red blood cells, the second part of the equation shows the amount of oxygen found in plasma
The PaO2 is normally measured in blood tests to evaluate the position in the the oxygen dissociation curve (this tells you how well oxygen is bound to Hb)
However, most oxygen is transported by the Hb in red blood cells as becomes clear from this equation. To calculate how much the PaO2 would have to be to compensate for a loss of Hb you get this:


Rise of the Oxygen solubility in plasma shows a linear relationship to PaO2
For a normal PaO2 of 90 mm Hg you get 0.003 x 90= 0.27
A normal CaO2 is about 200 ml/L, so for the PaO2 to compensate 199.73 ml/L O2 the PaO2 would have to rise by 199.73/0.27= 739.75 times
For conditions resembling hypoxemia (CaO2= +/- 163 ml/L with a corresponding PaO2 of 45 mm Hg) the PaO2 would have to rise 162.73/0.27=602.70 times normal (but 162.865/0.135= 1206.4 times higher compared to the hypoxic PaO2)
So I think you still need red blood cells.

As you can tell the contribution of oxygen transport by plasma is very limited. This is why in general the saturation is more important than the PaO2. Why do they evaluate the PaO2? Because the binding properties of oxygen to haemoglobin are represented by a curve (a sigmoid “oxygen dissociation curve”) rather then a linear relationship and that curve shifts according to the acidity of the blood. So it tells you something about how oxygen will bind to haemoglobin in red blood cells.

A higher atmospheric pressure may have some effect on the oxygen in plasma and that was the premise of the proposed treatment of carbon monoxide poisoning using hyperbaric oxygen (HBOT). Despite the HBOT enthusiasm, a critical meta-analysis shows no effect of hyperbaric oxygen in the improvement of carbon monoxide poisoning. Maybe future results will...

This is generally accepted as a valid scientific review in many medical fields called the Cochrane database of Systematical Reviews , here you find a meta-analysis weighing all the scientific papers on this subject of carbon monoxide poisoning and HBOT. HBOT enthusiasts see a conspiracy in this to prevent the use of HBOT.
Unfortunataly, I think Wikipedia is a little off here

When you consider that carbon monoxide is a competitive inhibitor of Haemoglobin (it competes with oxygen to bind to haemoglobin and wins), increasing the O2 fraction of normal air will improve the chance of O2 replacing CO. By administering 100% O2 ( about 5 times as much as normal air), in most cases CO can be replaced by O2 in about 30 minutes, since only a fraction of the Hb has been bound to CO. This may require intubation and mechanical ventilation, and can also be done at slightly higher then normal ventilation pressures for a short period of time. The actual treatment is replacing CO by O2 on haemoglobin, not increasing the plasma O2 concentration. Most HBOT chambers reach about 6 atm (going up to 37 atm) and show no real advantage to conventional treatment by mechanical ventilation, but are vastly more expensive, less available and complicate further treatment of the patient (patient is in a locked chamber, mostly unavailable for the doctor).
You can find Dr Elmer Cranton's rant on conventional treatment here
although I do think hyperbaric oxygen therapy is very valuable in certain diseases, this is not the point of the discussions. However, there are limitation to it's use and effectiveness which are part of the discussion not to opt for HBOT in some diseases/conditions.

Maybe slightly of topic from the OP, but I hope this clarifies a few things …

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Old 11th June 2007, 12:16 AM   #23
Dustin Kesselberg
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It's called Sulfhemoglobinemia that causes dark green blood caused by excessive amounts of sulfhemoglobin in the blood. The drug he was taking ,Sumatriptan, caused it.

Reminds me of the blue libertarian...

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Old 11th June 2007, 01:03 AM   #24
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There's also fetal hemoglobin, and it gets more complicated than that, see the illustration here.
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Old 11th June 2007, 01:16 AM   #25
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Originally Posted by whiteyonthemoon View Post
There's also fetal hemoglobin, and it gets more complicated than that, see the illustration here.
To keep it simple:
Yeah there is a medical subject called haematology.
However, what you have just mentioned is of some importance in early life but becomes rapidly less relevant after infancy. So keeping it simple, trying to clarify.

BTW, I think Dustin may just have answered the thread checking the link in the OP

compare with:
http://www.pubmedcentral.nih.gov/pic...7&blobtype=pdf
I'm pretty sure he has answered it...


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Old 11th June 2007, 08:13 AM   #26
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What the SPO2 of 97% is represents the HbO2% of arterial blood at:

Normal body temperature (37.5 C)
pH = 7.4
PaCO2 = 40 mmHg
PaO2 = 90 -100 mmHg
2,3DPG levels = Normal


This refers to the normal situation and not variations due to methemoglinemia which is usually caused by ingestion or exposure to nitrates or carboxyhemoglbinemia due to elevated carbon monoxide levels -- which while very interesting do not result in normal physiological values.

There are many ways to describe O2 transport but the basic is the O2-Hgb dissociation curve under conditions of normal temperature, PaCO2, PaO2, pH and 2,3 diphosphoglycerate.

As you can see from a normal curve the O2 sat is approx 97% at normal conditions when the
PaO2 is also normal around 90-100 mmHg.


http://www.ventworld.com/resources/oxydisso/dissoc.html

http://www.bio.davidson.edu/Courses/...ssociation.htm

or you can have fun with this one:

http://www.getbodysmart.com/ap/respi...animation.html


In the animal kingdom there are hundreds of different kinds of hemoglobins. In humans there are only 5 normal hemoglobins.

You can saturate hemoglobin only to 100% by delivering supplemental oxygen, e.g. oxygen above 21%, thereby raising the PaO2. Hgb carries 1.34 ccs of O2 per gm so a normal Hemoglobin of 12 gm carries a maximum of 1.34 x 12 gm = O2 content of 16.08 ccs of O2. However you can add more oxygen by dissolving more oxygen in the body's water and the only way I know of doing that is by using HBOT. I agree it is debatable whether this is necessry to get rid of CO from the hemoglobin. The only reason to use HBOT for CO poisoning is to provide oxygen to the person while they are clearing the CO they've inhaled. This could possibly = keeping the victim alive. At high HBOT pressures, I don't remember exactly how many ATAs, researchers have kept dogs oxygenated which have had their total blood supply replaced by Ringers and other fluids.

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Old 11th June 2007, 08:55 AM   #27
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Originally Posted by SteveGrenard View Post
What the SPO2 of 97% is represents the HbO2% of arterial blood at:

Normal body temperature (37.5 C)
pH = 7.4, PaCO2 = 40 mmHg, PaO2 = 100 mmHg, 2,3DPG levels = Normal
Originally Posted by SteveGrenard View Post
There are two kinds of oxygen in the body ... bound to hemoglobin and
dissolved. Normally 97% of the blood oxygen is of the bound type so yes would be the answer. However in a hyperbaric chamber you can increase the partial pressure of O2 so high that you can dissolve enough oxygen in the liquid part of the blood making the bound (to hemoglobin) unnecessary.
Ahh... Then maybe it would be better to say that the oxygen saturation of blood is normally higher then 95%. The statement the " bound type " of oxygen is 97% suggested that the other 3 percent was dissolved when you actually mean that normally 97% of the blood Hb is saturated or bound by oxygen. For the normal values we use normal ranges, but that's a bit hypercritical nitpicking.

The whole HBOT defense throws people even further off... The soluble fraction of O2 in plasma is very very low. Mostly nurses and paramedics get confused by this. After doing a blood gas analysis, the PaO2 is held as a sacred number to describe the oxygenation of the blood, when in fact it only begins to describe another process and does not contribute to the overall O2 transport at all. Felt I needed to clear this up since it is a very common misconception, leading to many errors in both thinking, communication and treatment.

Originally Posted by SteveGrenard View Post
This refers to the normal situation and not variations due to methemoglinemia which is usually caused by ingestion or exposure to nitrates or carboxyhemoglbinemia due to elevated carbon monoxide levels -- which while very interesting do not result in normal physiological values.
Actually up to 3% methaemoglobin is normal (less then 5%). Less then 5% carboxyhaemoglobin is also still normal. You see this a lot in smokers and is actually a fast test to evaluate whether someone may be a tabacco smoker or not when they come in to the hospital unable to answer questions (after trauma for instance). These are common disturbing factors and are often part of the blood gas analysis, because they can influence analysis of the Hb content. See the article referenced in the previous post

Originally Posted by SteveGrenard View Post
In the animal kingdom there are hundreds of different kinds of hemoglobins. In humans there are only 5 normal hemoglobins.
I presume you are a vet? So I gather you didn't understand why the comment was this critical of your statements. I hope this explains it.

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Old 11th June 2007, 10:02 AM   #28
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3% methemoglobin or 5% carboxyhemoglobin may be common but I wouldn't call them "normal."

No, I am not a vet. You don't have to be a vet to know there are several hundred different types of hemoglobin among non-human animals.
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Old 11th June 2007, 10:21 AM   #29
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Originally Posted by SteveGrenard View Post
3% methemoglobin or 5% carboxyhemoglobin may be common but I wouldn't call them "normal."

No, I am not a vet. You don't have to be a vet to know there are several hundred different types of hemoglobin among non-human animals.
Then what do you base your opinions on...
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Old 11th June 2007, 10:47 AM   #30
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Originally Posted by SYLVESTER1592 View Post
Then what do you base your opinions on...
What does anyone base an opinion of what is "normal" upon? I conceded these %s may be commonplace and have clinical relevance but when dealing with the pure physics of oxygen transport they are confounding factors.
Are you telling me that people who do not smoke and have not inhaled any CO have normal CO levels of up to 5%. I don't think so. I have seen many ABGS with carboxy levels of %1-2% and frequently less than 1%. You must see a lot of smokers. Carboxy levels of 5% may fall within some acceptable range for you, a range not requiring any action for example, but it is not strictly "normal." Normal would be zero. Having any CO is not normal.

On the issue of dissolved O2, the unalterable fact is that O2 dissolves in blood plasma at a rate of .003ml/mm PO2. This means that anyone with a normal PaO2 of 100 mmHg carries .03 ml dissolved in the plasma. This is a
minute amount of O2 content but are you telling me that if I place a patient in an HBOC at 6 ATAs and as a result deliver, breathing air only and at BP of
4,200 mmHg, an inspired PO2 of around 800 mmHg I would not increase the amount of oxygen dissolved in the plasma? And if one would deliver 50 or 100% Oxygen at 6 ATAs, resulting in inspired PO2 in the thousands, that this would not increase the O2 dissolved in the plasma and the tissues?

Last edited by SteveGrenard; 11th June 2007 at 10:50 AM.
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Old 11th June 2007, 11:04 AM   #31
SYLVESTER1592
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I think you need to look at the thread again and try to understand the argument rather then trying to start a fight here...

I think you answered most of the questions yourself if you look carefully. If you have looked at so many ABG's, and I think you also know the normal clinical practice for necrotising fasciitis, sepsis and CO intoxication.

There is the recommendation to keep the hematocrit above 0.30 which is far more effective then transporting someone to an HBOT centre. As you can see from the equations it makes a lot more sense too. (In most cases adding red blood cells does the trick of optimizing a patients condition)
Admittedly in necrotising fasciitis HBOT may be effective... But it's hardly ever done, because it complicates treatment immensely, not always to the benefit of a patient

Good luck with the HBOT research...

SYL
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Last edited by SYLVESTER1592; 11th June 2007 at 11:12 AM. Reason: Clarification benefit HBOT
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Old 11th June 2007, 01:29 PM   #32
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Originally Posted by SYLVESTER1592 View Post
I think you need to look at the thread again and try to understand the argument rather then trying to start a fight here...
I was just interested in clarifying some of the normal physiology and
terminology. Your input/responses have been appreciated.



Quote:
There is the recommendation to keep the hematocrit above 0.30 which is far more effective then transporting someone to an HBOT centre. As you can see from the equations it makes a lot more sense too. (In most cases adding red blood cells does the trick of optimizing a patients condition)

Admittedly in necrotising fasciitis HBOT may be effective... But it's hardly ever done, because it complicates treatment immensely, not always to the benefit of a patient
Some types of anemic hypoxia, including that caused by CO poisoning,
do not respond to keeping the HCT up. Nor would it be useful for patients with diabetic foot/leg ulcers as well as necrotizing fasciitis or patients with gangrene of the extremities or elsewhere due to poor or damaged circulation. Of course normalizing the blood volume (HCT) in a patient that is hemorrhaging (including giving clotting factors) is much much better than HBO. HBO, however, can be useful for sustaining CO poisoning patients, treating diabetic ulcers and bacterial necrosis as well as anaerobic infections.

Quote:
Good luck with the HBOT research...

SYL
Actually don't do HBOT research and never have. I just have used it or recommended it over the past 4 decades to the doctors of patients where it may've been indicated or of value. I am an RT specializing in critical care and a herpetologist interested primarily in snake bite and other toxic envenomations if that's what you want to know.

I also just wanted to clarify that there are only 5 normal human hemoglobins
and they don't include, by definition, either methemoglobin or carboxyhemoglobin. Two (1 & 2)) which occur in the embryo known as Gower-1 and Gower-2. (3) Hb F which appears about gestational week 8. And then there are 2 types of normal adult hemoglobin called (4 & 5)Hb A and Hb A2. I trust you agree that while they may be somewhat common in some populations, all other types of hemogolbin are technically abnormal....?

If there is anything new on this subject I may've missed I'd appreciate hearing about it. Thanks.

Last edited by SteveGrenard; 11th June 2007 at 01:52 PM.
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