Hydration System and Hypothermia

[Gutshot John]

For those guys that are in Afghanistan and other extremely cold environments do you use your hydration system to mitigate hypothermia by putting hot liquid (H2O) into an insulated camelbak? It would be a method of keeping core temp up without having to expend energy.

Assuming you do, how long can you expect that water to stay hot/warm during an op with insulation?

[AirTrafficControl]

I see where you're going with this. The ones that Ive seen wouldn't stay warm enough long enough without having an external heat source to supply the need warmth.

[sinister]

This is a historic problem. Leave canteens or Camelbaks out in sub-zero and they're gonna freeze (especially if you're in a static eyes-on recon or surveillance position).

Perhaps the biggest problem we have is keeping intravenous fluids (Ringer's, saline, etc.) in 1/2 and liter bags warm. You push a cold IV into a guy who needs it and you may be giving him a whole new set of things to worry about.

[militarymoron]

The ones that Ive seen wouldn't stay warm enough long enough without having an external heat source to supply the need warmth.
throw a small disposable heat pack (hand/foot warmer kind) into the insulated carrier next to the reservoir near the bottom on the opposite side of the tube.

[Skintop911]

throw a small disposable heat pack (hand/foot warmer kind) into the insulated carrier next to the reservoir near the bottom on the opposite side of the tube.

That's what I do.

It doesn't keep the water hot, or even warm (depends on enviro temp), but it does keep it from freezing.

Also, be sure to blow back into the tube to clear it of water, else it freeze.

[Gutshot John]

Perhaps the biggest problem we have is keeping intravenous fluids (Ringer's, saline, etc.) in 1/2 and liter bags warm. You push a cold IV into a guy who needs it and you may be giving him a whole new set of things to worry about.

When we did alpine/cold weather training keeping my IV bags unfrozen (I slept with them in my bag at night and kept them close to my body during the day, also had to distribute a few to marines to do the same) was less of a problem than warming them up to a usable temperature. We had an emergency and had to heat up the bags of IV fluid inverted in the hot water food containers left over from chow. Not exactly the best choice but you improvise. It also took a while to get it up to temp.

But theoretically speaking how long does an insulated reservoir keep fluid warm? Couple of hours?

I like the heater idea but it seems like you'd need dozens of packets for even a short op.