All You Should Know About Dehydration

Two-third of the human body is made up of water, most of it being inside the cell, or intracellular. The rest is seen outside the cells, but inside the blood vessels. When water that leaves the body is greater than the water that is taken in, dehydration occurs. Normally water is lost in many ways, such as breathing- to humidify the air, sweating- to cool the body, and urinating- to eliminate wastes from the body.

Body water is tightly regulated by the thirst mechanism and kidneys. Hormones such as anti-diuretic hormones work within the kidneys.

Causes of Dehydration

1. Excess loss of water:
   · Diarrhea
   · Vomiting
   · Excessive sweating –such as in fever
   · Diabetes- where high blood sugars take water with it in the urine
   · Burns- damage skin cannot hold water in

2.  Insufficient intake:
   · inability to drink 
   · disabled thirst mechanisms
   

Symptoms

In mild to moderate dehydration, symptoms include:
· dry mouth and mucus membranes
· thirst 
· decreased urine output
· headache, 
· lightheadedness
· muscle weakness

In severe dehydration, symptoms include:
· sleepiness in infants
· irritability and confusion in adults
· lack of sweating
· no urine output
· sunken eyes
· sunken fontanella in babies
· low blood pressure
· rapid heart beat
· fever
· delirium
· loss of consciousness

These are dangerous conditions which can lead to death very quickly if not treated. 

Diagnosis

• History- Patient may give a history of vomiting, diarrhea, heat exposure, fever.

• Physical examination- Inelastic skin, sunken fontanella, dry mouth and tongue, and in severe cases- decreased blood pressure and increased heart rate.

•  Labs- Electrolyte imbalances which show increased sodium and potassium, with concentrated blood.

• Urine analysis- Dark colored urine can be seen. Ketone bodies also may be present in the urine and specific gravity may be elevated. 
  Causes of dehydration should be identified.

Treatment

The only treatment is to replace the fluid and electrolytes which is deficient. Treatment depends on the severity of dehydration and the age of the patient. 

Mild dehydration can be treated by oral rehydration with electrolyte solution. If children and babies have diarrhea, they should have plenty of electrolyte fluids by mouth. These fluids should also supply glucose for energy. If there is both diarrhea and vomiting in young children, medical attention should be sought without delay. If electrolyte solutions are not available- this can be made at home by dissolving a half a teaspoon of salt, ½ teaspoon of baking soda, and 3 tablespoons of sugar in 1liter of boiled water. This solution can be used for temporary replacement. In babies, breast milk should be continued, and it is better to avoid lactose if bottle-fed. Plain water should also be avoided. 

In sick adults, oral hydration with plain water is best. Avoid fruit juices. Dehydration in athletes, cool water and electrolyte solutions are recommended.

Severe dehydration should be treated in a hospital setting with intravenous fluids. 

Prevention

Drinking at least 8 glasses of water per day helps keep patients hydrated. Increase intake in certain conditions, such as exercise, hot, humid weather, and fever. 

Complications of Dehydration

1. Decreased blood supply to the brain, leading to confusion and coma.

2. Decreased blood supply to the kidney, leading to kidney failure.

3.  Decreased blood supply to the vitals organs, leading to shock.

4. Electrolyte imbalance, leading to seizures, and heart abnormalities. 

Dehydration does not occur suddenly, but it has to be detected early and treated aggressively to avoid life-threatening complication, especially in the very young and very old.