Oxygen "Substitute"

[Seajack]

http://www.rawstory.com/rs/2012/06/...e-shot-can-keep-non-breathing-patients-alive/

I know very little about medicine, but I thought this was very interesting. From what I understand, this is way of giving oxygen through veins. What I don't understand is how it can make it to the brain if the patient isn't breathing, thus not sending blood/oxygen to the brain. Maybe with compressions?

Anyway, I hope you qualified guys would have an opinion on this, since medicine is a huge interest of mine and I'd like to read what you have to say about it.

 

[policemedic]

Here's the actual journal article. The science is interesting, but it's a long way off from practical use. This isn't approved for human use, and it will be years before it will be. The last test of an oxygen carrying compound didn't go so well, just ask Firemedic. Of course, the science here is completely different so results may be more promising. Regardless, much more work is required.

To answer one of your questions, a person's heart can beat even if they can't draw breath.

 

[pardus]

What I don't understand is how it can make it to the brain if the patient isn't breathing, thus not sending blood/oxygen to the brain. Maybe with compressions?

The lungs dont push blood around, the heart does and blood carries the O2 to the brain.

That said, One doesn't generally tend to work too well without the other lol but in theory as long as the heart is working (by itself or with help) and the blood is oxygenated, the brain should get O2 and keep on keeping on.

p.s. I havent read the article...

 

[Invictus]

The lungs dont push blood around, the heart does and blood carries the O2 to the brain.

That said, One doesn't generally tend to work too well without the other lol but in theory as long as the heart is working (by itself or with help) and the blood is oxygenated, the brain should get O2 and keep on keeping on.

p.s. I havent read the article...

Exactly. Issues start to arise when the other mechanisms associated with respiration (physiological) are not functioning e.g. getting rid of CO2.

Seajack I have some solid non-copyrighted science materials I can send your way if interested. Anatomy, kinesiology, nutrition, chemistry...

 

[amlove21]

This stuff comes out every so often, and it always seems to end up the same way. "Hey! We found a non-blood fluid to replace O2, this is going to be awesome! Buy our shares!" and then that compound gets shot down by the FDA. I think we are getting closer, but we still aren't anywhere close. And to make the jump to actual pre-hospital/polytrauma use? That's going to be more than a little bit, methinks.

 

[policemedic]

This stuff comes out every so often, and it always seems to end up the same way. "Hey! We found a non-blood fluid to replace O2, this is going to be awesome! Buy our shares!" and then that compound gets shot down by the FDA. I think we are getting closer, but we still aren't anywhere close. And to make the jump to actual pre-hospital/polytrauma use? That's going to be more than a little bit, methinks.

Exactly.

I think getting IRB approval for something like this in human trials will be difficult. Authorizing a study that randomly assigns people to receive, say, an ET tube or cric and mechanical ventilation vs. the injectable oxygen substitute is going to be a hard sell. I realize this would be way down the line, but still...

My academic curiosity is aroused, but I remain skeptical.

 

[Muppet]

Here's the actual journal article. The science is interesting, but it's a long way off from practical use. This isn't approved for human use, and it will be years before it will be. The last test of an oxygen carrying compound didn't go so well, just ask Firemedic. Of course, the science here is completely different so results may be more promising. Regardless, much more work is required.

To answer one of your questions, a person's heart can beat even if they can't draw breath.

Hey. You talking about the giant failure called Polyheme? Big failure.

F.M.

 

[policemedic]

Hey. You talking about the giant failure called Polyheme? Big failure.

F.M.

Yep, that would be the 500cc bag of fail I was referring to. You know more about that trial than I do.

 

[Red Flag 1]

Hey. You talking about the giant failure called Polyheme? Big failure.

F.M.

Yes it was. Polyheme was intended to be a substitute for banked blood, dating from the early to mid '60s, http://biomed.brown.edu/Courses/BI108/2006-108websites/group09artificialblood/Pages/polyheme.htm, this; however, is quite a different agent. This directly IV injected substance (oxygenated liposomes), could well be the answer to hypoxia; if it is safe. Imagine the comfort of having such an agent in your toolbox when you are struggeling secure an airway, http://www.medicalnewstoday.com/articles/247295.php. Another article, this one from "Scientific American", http://www.scientificamerican.com/podcast/episode.cfm?id=iv-oxygen-foam-could-buy-breathing-12-06-27. Yet another article, from "Circulation", http://circ.ahajournals.org/cgi/content/meeting_abstract/122/21_MeetingAbstracts/A6. These are in addition to the study PM posted.

There seems to be quite some interest in this agent of oxygenated liposomes, and for good reason. Diamonds are the result of carbon compounds exposed to tremendous heat and pressure over long periods of time; I suspect I have produced a diamond or two in my own anus, as I was dealing with an impossible airway or two. An agent such as this would have deprived the world a few of my diamonds. Oxygenated liposomes hold promise, as seen in animal studies. There are many questions to be considered; questions about metabolites, active and inactive,; interface with other drugs; effects of, and on acidosis, and alkalosis; excretion pathways; protein binding sites, and a host of other questions. All questions are considered in the face of a clear need for just such an agent, and the risk benefit ratio. Let us pray that it does not become a political/funding casuality.

Thanks for bringing this up Seajack!!

RF 1

 

[DoctorDoom]

To be clear, this is not intended to be a blood substitute like Polyheme. Very different intended purpose and potential indications.

 

[policemedic]

To be clear, this is not intended to be a blood substitute like Polyheme. Very different intended purpose and potential indications.

Very true. Polyheme was intended both for volume replacement and to carry O2, something only blood can do. This stuff is virtually time-release O2 in a syringe. However, they are both similar in that they are both artificial means of distributing O2. I've read the article a few times now, and it's fascinating. I just remain skeptical (though hopeful).

As Red Flag 1 noted, there are challenges ahead for this compound. I will be very interested to see how the research progresses.

Speaking of research, how do you see human clinical trials being structured? For instance, you could intubate a series of patients and use vecuronium (and sedatives, of course) then administer the injectable O2 and record the various metrics. If things don't go to plan, you have a secured airway and can ventilate. But would an IRB approve this, and if they did, could a sufficient number of pts be enrolled to make the results statistically significant? I'm obviously more of a critical consumer of medical research than a participant; my practical knowledge of study design is two steps above nil. I'd be interested to hear your thoughts.

 

[DoctorDoom]

The research structure would be quite similar to the one used for Polyheme, I would imagine, in certain respects. They would be only acute patients that fit the criteria of no spontaneous respiration and not pulseless, or at least with a shockable rhythm. Likely an ICU setting would be preferred over an emergent setting at first, although certainly trauma or even pre-hospital settings would be valuable. I mean think of those patients who cannot be intubated or ventilated in the field in a major city that could get a shot of this and go straight to trauma surgery for a definitive surgical airway! Patients would need to be randomized to treatment and control (current treatment protocol) groups. Enrollment would take a long time as the very specific eligibility criteria would mean very few patients would qualify, and so a multi-center trial would be necessary. Thus significance can be achieved only over a long period of time in many participating institutions. Starting with large animal trials would be able to demonstrate proof of principle, and I bet the military would play a role, especially when it came time to apply for fast tracking with the FDA. Consent would be easier to obtain in the ICU setting, which is a big reason why I would think that would be initially preferable, but like Polyheme and Hemopure trials in emergent situations would rely on implied consent, which are carefully monitored by IRBs and FDA.

These are kind of off the top of my head, but I think for sure a long trial process in several centers describes the most likely scenario. Endpoint would ideally be total mortality within 30 days. I would love to get involved in the trials somehow... just not as a patient!

Hope this is useful for you man.

 

[policemedic]

It's very useful; thanks for putting it up. You validated what I was thinking.

 

[Etype]

It'd be interesting if they could work out a drip rate for an infinite breath hold.

 

[dknob]

like the shit from The Abyss?

 

[DoctorDoom]

The stuff from the Abyss is inhaled and not injected, and it actually exists... for rats.