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Oxygen injections can save lives

A new first aid technique delivers oxygen straight into the bloodstream to keep you alive even if you can't breathe. Dr Karl explains how this invention can buy a few minutes of extra time.

The word 'resuscitation' literally means to revive somebody from unconsciousness, or impending death.

Resuscitating sick people has been part of our human medical history for thousands of years. But now there's a new way to resuscitate someone — injecting oxygen directly into their bloodstream. This can keep you alive — even if you can't breathe.

Blood is about 55 per cent salty water, and about 45 per cent cells.

The salty water is called 'blood plasma'. The 55 per cent, the blood plasma, contains various chemicals such as proteins, glucose, iron, hormones, fatty acids, dissolved carbon dioxide and the like.

The cells, the 45 per cent, are mostly red blood cells, with much smaller numbers of white blood cells and platelets. The red blood cells are jampacked with an iron-containing protein called haemoglobin. Haemoglobin is really good at carrying oxygen. Normally haemoglobin picks up the oxygen when it enters the lungs, and then delivers it to where it's needed.

Now let's suppose you've been in some kind of terrible accident (say an earthquake or a car crash) and your airway is blocked. Your heart can still beat, but no new air is getting into your lungs — so your blood is not picking up any oxygen. By an amazing and lucky coincidence, the medical emergency people happen to be with you — but it's going to take them 15 minutes to open up your airways. You're going to be dead within four minutes, unless you can get oxygen some other way.

This is exactly where the new resuscitation invention steps in. The emergency people grab a bottle of a 'special' liquid, and start injecting it into your bloodstream. This liquid supplies your red blood cells (and you) with oxygen, and keeps you alive until the emergency people can fix whatever is blocking your airways. They still have to do this in less than 15 minutes, but that gives them a lot more working room than just four minutes

This magical product was developed by a team at the Boston Children's Hospital. It goes under the fancy name of 'lipidic oxygen-containing microparticles'. In plain English, it's a tiny ball of high-pressure oxygen, surrounded by a very thin wall of fat.

Now these hollow balls are around two to four microns in diameter. (A micron is 1 millionth of a metre, and your hair is around 50 to 70 microns in diameter). The thickness of this wall of fat is one thousandth of the diameter of the hollow sphere, or about two billionths of metre. Because these hollow balls are so tiny, the oxygen inside them is at very high pressure. There is a lot of oxygen stored in these hollow balls. There are about 10 billion of these oxygen-containing hollow balls per litre of liquid.

After the team had manufactured a bottle of oxygen balls, they tested it on themselves.

Let me quote Dr John Kheir: "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".

Now of course, deoxygenated blood is not really blue, it's more of a dark dark red — but you get the idea.

Their second study was done with anaesthetised rabbits. They blocked the airways of the rabbits. If they had done nothing, the animals would have been dead within minutes. But they then infused their oxygen-containing microparticles into the bloodstream of the rabbits — and they stayed alive for the next 15 minutes.

The microparticles, once they are transferred to the bloodstream, immediately give up their oxygen to the nearest deoxygenated red blood cells. But what happens to the very thin fatty wall of one of these hollow microparticles? Once it is empty of oxygen, this wall of fat breaks down by folding itself into millions of smaller solid balls of fat.

Now while this magic oxygen-containing liquid works, it is not a perfect solution to the problem of a blocked airway.

First, the microparticles come in a liquid. There's a limit to how much liquid you can add to a circulatory system before the heart (which is a pump) gets overloaded.

Second, while the microparticles deliver oxygen, they do not remove the carbon dioxide you continue to generate. The carbon dioxide dissolves in the blood plasma and slowly makes it more acid. After about 15 minutes, your blood is too acid to support life any more.

Third, the team has not fully worked out what happens to the fats as they break down.

But as a simple first aid approach, this 15-minute solution to the problem of keeping somebody supplied with oxygen while you open up their airways is terrific.

And with my crystal ball, I'd like to predict elite athletes won't be soon queuing up to buy their own stash of this magic bottled oxygen ... but don't hold your breath.

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