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Pretty interesting and trying to RTB. Woot woot.
ScienceDaily (June 27, 2012)— Patients unable to breathe because of acute lung failure or an obstructed airway need another way to get oxygen to their blood -- and fast -- to avoid cardiac arrest and brain injury. A team led by researchers at Boston Children's Hospital has designed tiny, gas-filled microparticles that can be injected directly into the bloodstream to quickly oxygenate the blood.The microparticles consist of a single layer of lipids (fatty molecules) that surround a tiny pocket of oxygen gas, and are delivered in a liquid solution. In a cover article in the June 27 issue ofLuck_The_Fakers_Science Translational Medicine, John Kheir, MD, of the Department of Cardiology at Boston Children's Hospital, and colleagues report that an infusion of these microparticles into animals with low blood oxygen levels restored blood oxygen saturation to near-normal levels, within seconds.When the trachea was completely blocked -- a more dangerous "real world" scenario -- the infusion kept the animals alive for 15 minutes without a single breath, and reduced the incidence of cardiac arrest and organ injury.The microparticle solutions are portable and could stabilize patients in emergency situations, buying time for paramedics, emergency clinicians or intensive care clinicians to more safely place a breathing tube or perform other life-saving therapies, says Kheir."This is a short-term oxygen subs ute -- a way to safely inject oxygen gas to support patients during a critical few minutes," he says. "Eventually, this could be stored in syringes on every code cart in a hospital, ambulance or transport helicopter to help stabilize patients who are having difficulty breathing."The microparticles would likely only be administered for a short time, between 15 and 30 minutes, because they are carried in fluid that would overload the blood if used for longer periods, Kheir says.Kheir also notes that the particles are different from blood subs utes, which carry oxygen but are not useful when the lungs are unable to oxygenate them. Instead, the microparticles are designed for situations in which the lungs are completely incapacitated.Kheir began investigating the idea of injectable oxygen in 2006, after caring for a little girl who sustained a severe brain injury resulting from a severe pneumonia that caused bleeding into her lungs and severely low oxygen levels. Despite the team's best efforts, she died before they could place her on a heart-lung machine. Frustrated by this, Kheir formed a team to search for another way to deliver oxygen."Some of the most convincing experiments were the early ones," he says. "We drew each other's blood, mixed it in a test tube with the microparticles, and watched blue blood turn immediately red, right before our eyes."Over the years, Kheir and his team have tested various concentrations and sizes of the microparticles to optimize their effectiveness and to make them safe for injection. "The effort was truly multidisciplinary," says Kheir. "It took chemical engineers, particle scientists and medical doctors to get the mix just right."In the studies reported in the paper, they used a device called a sonicator, which uses high-intensity sound waves to mix the oxygen and lipids together. The process traps oxygen gas inside particles averaging 2 to 4 micrometers in size (not visible without a microscope). The resulting solution, with oxygen gas making up 70 percent of the volume, mixed efficiently with human blood."One of the keys to the success of the project was the ability to administer a concentrated amount of oxygen gas in a small amount of liquid," Kheir says. "The suspension carries three to four times the oxygen content of our own red blood cells."Intravenous administration of oxygen gas was tried in the early 1900s, but these attempts failed to oxygenate the blood and often caused dangerous gas embolisms."We have engineered around this problem by packaging the gas into small, deformable particles," Kheir explains. "They dramatically increase the surface area for gas exchange and are able to squeeze through capillaries where free gas would get stuck."The study was funded by three awards from the Technology Development Fund at Boston Children's Hospital Boston and a U.S. Department of Defense Basic Research Award to Kheir.
http://www.sciencedaily.com/releases...0627142512.htm
Last edited by Viva Las Espuelas; 07-02-2012 at 08:46 AM.
What is "RTB"?
Raise the bar?
I thought the article was more interesting imho
Ah, okayMy first thought was "read the book" and how extremely boring that would be! lol
Ah.
So, I was just thinking, and this is to anyone in the medical field here. What would this do to a normal person that's not having an emergency? If this was injected in them. I'm just asking from a standpoint of this injection being abused which might happen, someway.
Well oxygen has dangerous side effects breathed in high concentrations or in hyperbaric conditions. There's really no way to know what effects this other method has until these guys who are pioneering it, figure it all out and tell us. If you are thinking it may be abused because it causes some form of euphoria or other pleasurable side effects, again there is no way know that from the article.
pretty interesting indeed.
Ah. Wikipedia.
Congrats on 13K.
Not a doctor yet but I would automatically assume it would not be as efficient of a oxygen pick up had that same blood picked up oxygen in the lungs. Physiologically, a human body is accustomed to how things go...physiological processes all too often undergo some sort of change only for the body to revert back to the original state in a sort of dynamic equilibrium (homeostasis). A human lung evolved perfectly for oxygen-carbon dioxide exchange.
To rely on oxygen pick up elsewhere would surely decrease the efficiency with which red blood cells are oxygenated.
But in a life and death situation, I guess any and every possible life saving idea is fair game.
I wonder how they expel CO2?
Not a doctor by any stretch of the imagination, so I can only assume patients' blood cells would carry out CO2 the same way they carried the oxygen in. But you raise some interesting questions: 1) are oxygen and carbon dioxide respectively absorbed and excreted in a 1:1 ratio +/-? And; 2) can blood cells carry as much CO2 as they can oxygen? If the answer to either or both question is "no," I expect a patient's heart rate would have to elevate in proportion to the amount of CO2 it needed to expel.
Well for short term (15 min like they say here), it probably doesn't matter. The benefits of oxygen far outweigh the dangers of the CO2 in a life or death situation. For the longer term, heart lung bypass machines and ECMO (extracorporeal membrane oxygenation) machines remove CO2 and oxygenate blood quite well. Unfortunately, these are all great things to have, but without functioning lungs, they can't amount to much.
Pt's on ECMO are pretty much ED, maalox
This treatment is interesting because it's being pioneered at a children's Hospital...that's the one demographic where over-oxygenation and oxygen toxicity is quite prevalent and even deadly in certain conditions.
Well it would really depend on what caused the hemoglobin not to efficiently take up the oxygen. If its a critical obstruction to the airways, like with what happens in various lung injuries, you can safely assume the body wouldn't be able to expel CO2 because that same passage would be obstructed.
Technically, heme (part of the hemoglobin) will bind to 4 molecules of Oxygen because of its affinity. With every one oxygen molecule bound, a thing called postive cooperativity allows more oxygen bind with a maximum number of 4 oxygen molecules per HG.
The same positive cooperativity doesn't apply to CO2 because of lesser affinity. Thus, some argue it's one and if at most two molecules of CO2 that will be expelled.
So it's either 4:1 or 4:2 depending on different cir stances relevant to the chemical and physical state of the hemoglobin molecule.
A patients heart rate stays dynamic with regard to circulatory dynamics. There are other variables that must be accounted for in addition to needing to inhale O2 and expel CO2...in other words, it depends on the cir stances of your body physiology and environment in which your situated.
Like if your exercising, heart rate obviously increases to satisfy the need to inhale oxygen and expel CO2 (a waste)... There are other cases when this isn't so.
Oh yea they sure are. But in neonatology, ECMO can at least buy some time till the lungs mature and function normally. But that's the kicker, lungs that function normally----without those, it's kinda hard to get excited about any of these advances. I mean, I can see where the injection in the article can be beneficial in a situation where there is difficulty getting someone intubated/oxygenated right away, I'm sure you agree an extra 15 minutes would be a luxuryPt's on ECMO are pretty much ED, maalox
This treatment is interesting because it's being pioneered at a children's Hospital...that's the one demographic where over-oxygenation and oxygen toxicity is quite prevalent and even deadly in certain conditions.
True, time is everything, so if this can buy you some during resuscitation or other procedures then shiiiit....why not.Oh yea they sure are. But in neonatology, ECMO can at least buy some time till the lungs mature and function normally. But that's the kicker, lungs that function normally----without those, it's kinda hard to get excited about any of these advances. I mean, I can see where the injection in the article can be beneficial in a situation where there is difficulty getting someone intubated/oxygenated right away, I'm sure you agree an extra 15 minutes would be a luxury
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