Dehydration can be more complicated in the field of medicine than just volume depletion. A true diagnosis of dehydration cannot be made with assessing urinalysis and serum sodium levels. We can make determinations in the outdoors that can at least help one get back on their feet and hopefully back to a vehicle to get treatment at an Emergency Room or Urgent Care setting.
Volume depletion is when the total body water ( TBW ) which is normally 50 to 60 percent of a persons weight, is lowered due to less intake than output. That output can be urine, sweat, diarrhea, and emesis.
Fever, for example, can increase depletion by 500 ml per degree of temperature. Also, there can be volume depletion by blood loss. All of this needs to be factored in when assessing dehydration ie volume depletion. In fact, it is important to know your camper or hikers medical history as well. Diabetes, autoimmune disorders and a multitude of other illnesses can factor in when assessing dehydration.
- Muscle cramping
- Postural lightheadedness Standing up and feeling lightheaded ( Not vertigo )
- Abdominal pain
- Change in Mental Status ( unsure of where you are, confused and disoriented)
- Increased urination ( in early stages )
Assessing Dehydration in the Field
For the majority of hikers and campers in the outdoors, you will be limited in your ability to assess this. There are a few techniques that can be helpful along with good old common sense.
- Orthostatic vital signs. (Pulse and blood pressure) You will most likely not have a BP cuff, so let’s look specifically at the pulse rate. Take the individuals pulse while they are sitting or lying down and record it. Next, have them stand for three minutes and retake their pulse. If their pulse increases by 20 beats per minute or higher they can be dehydrated. Volume depletion means the heart has to pump faster to get blood to the brain, hence, lightheadedness and increased pulse rate.
- Mucous membranes are dry. Tongue and back of throat is dry. ( cotton mouth feeling)
- Urine is darker in color.
- In children and infants – no tears when crying.
- Sunken eyes.
- Increased urination – early stages and decreased urination – middle to late stages.
Dehydration Treatment Ideas in the Backcountry
- Try drinking at least 16 ounces of fluid 2 hours before hiking or exertion.
- Being thirsty does not translate to dehydration. Many individuals can be up to 10 percent dehydrated before they feel thirsty.
- Drinks with electrolytes are often a money-maker and have great ads to sell you into replenishing electrolytes. They do little to nothing for rehydration of electrolytes. Research it, do your due diligence. Water is your best bet.
- Small meals should be eaten. Often, five small meals are better than three large meals. THIS will help with rehydration and electrolytes.
- Drinking about 5 ounces of water every twenty minutes is highly advisable on long hikes and outdoor exertion.
- As per Dr. Auerbach; After exercise, one should drink 32 ounces of water for every kilogram of weight lost during exercise. Clearly, this is not going to happen in the outdoors unless you carry a scale in your vehicle. It is helpful when working out and getting prepped for an outdoor excursion.
- Remember that water requirements in the cold are equally as important in the heat. In the cold, one may need up to 2 quarts a day and in the cold with exertion – up to 2 gallons.
- At high altitudes, water intake can be equal to that in a desert. Altitudes above 10,000 feet – over 2 gallons is required. Remember, you want your urine to be a pale yellow.
Survival and Drinking Water
This will be covered more extensively in water disinfection, however, this is so important. Survive Outdoors will bring this up at various times. When lost, always drink the water. The most common organism in North America that caused diarrhea is Giardia Lambia – often called, “Beaver Fever.” It is called Beaver Fever NOT because of contamination from just beavers, but because of mammals defecating in streams and lakes. It has been isolated in stool from dogs, cats, coyotes, voles, muskrats and even birds. The incubation for Giardia is about three weeks. Drink the water. You will be found in less than three weeks more often then not and at least you will be hydrated and you can be treated when symptomatic. IT IS ESTIMATED THAT 80% OF THE WATER IN North America IS INFECTED WITH GIARDIA. THIS DOES NOT MATTER IF IT’S A RUNNING STREAM IN THE TETONS OR A PLACID LAKE IN WISCONSIN.