[Doczilla]

We've moved away from salt tablets in preventing/treating heat casualties. SouthernDZ is exactly right in everything that he said. It is important that the soldier/potential patient continues to maintain adequate salt intake, particularly when water intake exceeds 4L/day. MREs have adequate salt content, so it's important to emphasize the need to eat their meals. They can't just drink and not eat anything. Monitoring urine output is a good way to monitor hydration status. The darker the pee, the more dehydrated they are. If they are humping for 8 hours without urinating once, they are dehydrated.

Forced water hydration, particularly more than 4L in a few hours, can potentially lead to hyponatremia (decreased sodium level), especially if there hasn't been adequate salt intake. Gatorade and Powerade are highly engineered drinks which provide some amount of sodium to prevent hyponatremia from overaggressive free water hydration. Gatorade has about 2x the sodium of Powerade, and about the same amount of potassium. Gatorade Endurance has double the amount of sodium and 3 times the amount of potassium of regular gatorade. I'd probably cut this latter formula with water.

Other than that, prevention of heat casualties relies on appropriate clothing, frequent rest breaks, protection from the sun, and early intervention on any illnesses that could potentially worsen dehydration, such as nausea, vomiting, diarrhea, fever, or infection. Make sure they drop their gear and fan themselves off frequently. In that weather, with lots of gear, drop for 10 minutes twice an hour.

Prevention and early recognition is key. As the casualty becomes nauseated, dizzy (particularly on standing), fatigued, suffers performance decrement, is confused, has difficulty thinking or solving problems, begins stumbling, is making poor decisions, is thirsty, has a high heart rate not related to exercise, they are dehydrated and potentially hyperthermic, and you should intervene. A high heart rate and no sweating in a confused or obtunded casualty means heat stroke, and they need to be cooled immediately and aggressively. As long as the casualty can drink and won't throw it up, you don't need an IV. Drink in small quantities as a time to prevent vomiting.

'zilla

Edit: hypERthermic, not hyPOthermic. My bad.