It’s amazing how this phenomenon has been adapted into medical technology. When my son was born he wasn’t breathing properly and his blood oxygen levels dropped to critical levels. He was rushed to hospital and the first thing they did was cool him to 34c to reduce the risk of brain damage. He made a full recovery. I dread to think what would have happened without the cooling.
Same thing happened when my son was born and he had complications resulting in loss of blood to the brain for a significant amount of time. We were told to expect mild to moderate brain damage while we just had to sit and wait as they basically did nothing but keep him cooled for about three days. It's been three years now and he very smart and extremely athletic. The doctors said the cooling is what the difference. His complications happened at the hospital so he was able to be cooled immediately.
Why not cool the patient before rushing them to hospital, if the technique is so widely applicable? It could easily be made a standard feature of emergency medical services.
Because it's hard. I helped out at a company among many that are trying to develop a system that would allow you to do this in ambulance and they started testing prototypes 10 years ago and have yet to progress from that stage.
It's not that hard... you just throw some ice packs in the groin and armpits. You won't get them fully into the TTM range in a 20 minute transport, but you can start the process.
Packing with ice packs is a standard component of TTM, generally in conjunction with other therapies (chilled IV fluids, etc). It's also the easiest step to take in a prehospital setting, which is why we do (this is a thing I've done with maybe a dozen patients over the past few years). I'm not just making this stuff up, it's based on actual treatment protocols and algorithms.
We're talking about a naked, sedated patient (so they're already losing a lot of heat due to simple convection, and there's no heat being generated by skeletal muscle movements). The body's metabolism has slowed significantly, and it's producing anywhere near the normal level of "baseline" heat.
Do you have any links to data showing effects on brain temperature from that treatment?
Afaik interest has been low in carrying around enough ice pack capacity to make this viable, and with lacking data for it even working, whereas head-cooling packs with circulating liquid through a cooler takes little space, cools way more efficiently and required no other maintenance after insertion into the patient in the ambulance (and is moved with the patient while continously working).
Overcooling is more of a risk with I've packs than not cooling enough. It's much less of a concern in a prehospital setting though, since we're not with the patient that long. It's more of an issue in the ICU.
This procedure is initiated after the heart has been restarted[1]. You're absolutely correct that it's pointless to do it earlier, especially since the far more important thing is getting the heart beating again.
[1] This is known as "targeted temperature management" (TTM), and is part of the standard post-ROSC (return of spontaneous circulation) algorithm in ACLS (Advanced Cardiac Life Support), if you're looking for terms to Google.
It will but much more slowly. Think of cooling the blood as using the surface area of the arteries and veins as a heat sink to cool the body. Without that blood moving your next best heat sink is the skin so start piling on the ice.
The body itself is the heat sink. The skin is a radiator. The blood is the liquid in a liquid cooling system (moving heat from the sink to the radiator). To your point, liquid cooling systems become _much_ less effective when the liquid stops pumping.
Those spots are not prone to frostbite, since the "coldness" gets distributed through the rest of the body very quickly (apologies for playing a little fast and loose with thermodynamics there). This is why they're used in the first place to cool the person quickly.
The process is called "targeted temperature management" and it's pretty common in EMS protocols. It's a part of the standard cardiac arrest "algorithm".
> Because creating a cooling system to use on a body with a central nervous system fighting to keep it warm
And yet, something as simple as ice cold water seems to work fine for this. You can cool e.g. even a heatstroke victim pretty quickly, without worrying too much about internal thermoregulation.
> a central nervous system fighting to keep it warm
A heat stroke victim the body is fighting to cool itself and failing. You assist. That part is easy.
Getting the body to do the opposite of what you want is the hard part. ie. Cool down below basal body temperature, stop breathing to perform thoracic surgery.
There are a lot of trials involving prehospital cooling.
Some groups focus on trying to cool the entire body by putting ice packs in areas of the body with lots of blood flow near the surface. Others focus on intranasal methods for cooling just the brain.
It's exciting stuff, but it's definitely not widespread.
