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Dehydration Treatment Plans

Why is Dehydration so Dangerous?

Why is Dehydration so Dangerous?
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On-page links
The symptoms of dehydration On-site links
What to do if Dehydration Occurs
Dehydration Treatment Plans
from WHO Supervisory Skills course
How is dehydration treated?
How to prevent dehydration

Off-site links
Heat and Hydration
Hyponatremia - Salt and the Ultraendurance athlete.
Hyponatremia --II : A more technical discussion, of the mechanisms responsible for the development of exercise associated hyponatremia. Dehydration and Heat Injury. Fluid Balance Test, Glycerol and hydration

Dehydration types, causes, symptoms and treatment

Acute diarrhoeal diseases are among the leading causes of mortality in infants and young children in many developing countries. In most cases, death is caused by dehydration. Dehydration from diarrhoea can be prevented by giving extra fluids at home, or it can be treated simply, effectively, and cheaply in all age-groups and in all but the most severe cases by giving patients by mouth an adequate glucose-electrolyte solution called Oral Rehydration Salts (ORS) solution.

During diarrhoea there is an increased loss of water and electrolytes (sodium, chloride, potassium, and bicarbonate) in the liquid stool. Water and electrolytes are also lost through vomit, sweat, urine and breathing. Dehydration occurs when these losses are not replaced adequately and a deficit of water and electrolytes develops. The volume of fluid lost through the stools in 24 hours can vary from 5 ml/kg (near normal) to 200 ml/kg, or more. The concentrations and amounts of electrolytes lost also vary. The total body sodium deficit in young children with severe dehydration due to diarrhoea is usually about 70110 millimoles per litre of water deficit. Potassium and chloride losses are in a similar range. Deficits of this magnitude can occur with acute diarrhoea of any etiology. The most common causes of dehydration are rotavirus, enterotoxigenic Escherichia coli (ETEC) and, during epidemics, Vibrio cholerae O1 or O139. Dehydration is the loss of water and salts from the body. The human body needs water to maintain enough blood and other fluids to function properly. Along with the fluids, the body also needs electrolytes, which are salts normally found in blood, other fluids, and cells. The body may lose fluids in a variety of ways:

  • when urinating
  • when you vomit or have diarrhoea
  • when sweating
  • from the lungs during normal breathing.

If the body loses a substantial amount of fluids and salts and they are not quickly replaced; for example: by drinking, the body starts to "dry up" or get dehydrated. Severe dehydration can cause death. The usual causes of dehydration are a lot of diarrhoea and vomiting. Dehydration can also occur if you do not eat or drink much during an illness or if you do not drink enough during or after strenuous exercise. Medications that cause fluid loss to control excess body fluid (diuretics) are a common long-term cause. Although anyone can become dehydrated, those who become dehydrated the most easily are:

  • babies under 1 year old
  • the elderly
  • anyone who has a fever
  • people in hot climates.

Dehydration caused by diarrhoea is one of the biggest single killers of children in the modern world and diarrhoea itself is one of the major causes of nutritional loss and poor growth. This year, about 2.2 million children will die of dehydration caused by diarrhoea - 80% of them in the first two years of their life.
What are the symptoms of dehydration? The degree of dehydration is graded according to signs and symptoms that reflect the amount of fluid lost:

In the early stages of dehydration, there are no signs or symptoms. Early features are difficult to detect but include dryness of mouth and thirst

symptons of dehydration

As dehydration increases, signs and symptoms develop. These include: thirst, restless or irritable behaviour, decreased skin turgor, dry mucous membranes, sunken eyes, sunken fontanelle (in infants), and absence of tears when crying vigorously. Symptoms of early or mild dehydration include:

  • flushed face
  • extreme thirst, more than normal or unable to drink
  • dry, warm skin
  • cannot pass urine or reduced amounts, dark, yellow
  • dizziness made worse when you are standing
  • weakness
  • cramping in the arms and legs
  • crying with few or no tears
  • sleepy or irritable
  • unwell
  • headaches
  • dry mouth, dry tongue; with thick saliva.

Symptoms of moderate to severe dehydration include:

  • low blood pressure
  • fainting
  • severe muscle contractions in the arms, legs, stomach, and back
  • convulsions
  • a bloated stomach
  • heart failure
  • sunken fontanelle - soft spot on a infants head
  • sunken dry eyes, with few or no tears
  • skin loses its firmness and looks wrinkled
  • lack of elasticity of the skin (when a bit of skin lifted up stays folded and takes a long time to go back to its normal position)
  • rapid and deep breathing - faster than normal
  • fast, weak pulse

In severe dehydration, these effects become more pronounced and the patient may develop evidence of hypovolaemic shock, including: diminished consciousness, lack of urine output, cool moist extremities, a rapid and feeble pulse (the radial pulse may be undetectable), low or undetectable blood pressure, and peripheral cyanosis. Death follows soon if rehydration is not started quickly.


From Wikipedia, the free encyclopedia

ICD-10 E86
ICD-9 276.5

Dehydration (hypohydration) is the removal ofwater (hydor in ancient Greek) from an object. Medically, dehydration is a serious and potentially life-threatening condition in which the body contains an insufficient volume of water for normal functioning.

The term "volume depletion" is similar to dehydration, but it refers to the loss of salts as well as water. Also see Hypovolemia.



Medical causes of dehydration

In humans, dehydration can be caused by a wide range ofdiseases and states that impair water homeostasis in the body. These include:

Symptoms and prognosis

Symptoms may include headaches similar to what is experienced as ahangover, a sudden episode ofvisual snow, decreased blood pressure (hypotension), and dizziness orfainting when standing up due to orthostatic hypotension. Untreated dehydration generally results indelirium, unconsciousness, anddeath.

Dehydration symptoms generally become noticeable after 2% of one's normal water volume has been lost. Initially, one experiencesthirst and discomfort, possibly along with loss ofappetite and dry skin.Athletes may suffer a loss of performance of up to 50%, and experience flushing, low endurance, rapidheart rates, elevated body temperatures, and rapid onset of fatigue.

The symptoms become increasingly severe with greater water loss. One's heart and respiration rates will increase to compensate for decreased plasma volume and blood pressure, while body temperature may rise because of decreased sweating. Around 5% to 6% water loss, one may become groggy orsleepy, experience headaches ornausea, and may feel tingling in one's limbs (paresthesia). With 10% to 15% fluid loss, muscles may become spastic, skin may shrivel and wrinkle, vision may dim, urination will be greatly reduced and may become painful, and delirium may begin. Losses of greater than 15% are usually fatal. [1]


Correction of a dehydrated state is accomplished by the replenishment of necessary water and electrolytes (rehydration). Even in the case of serious lack offresh water (e.g. atsea or in adesert),drinkingseawater or urine does not help, nor does the consumption ofalcohol. It is often thought that the sudden influx ofsalt into the body from seawater will cause the cells to dehydrate and thekidneys to overload and shut down but it has been calculated that average adult can drink up to 0.2 liters of seawater per day before the kidneys start to fail.

When dehydrated, unnecessarysweating should be avoided, as it wastes water. If there is only dry food, it is better not to eat, as water is necessary fordigestion. The best treatment for minor dehydration is consumption of an electrolyte-balanced fluid like a sports drink. For severe cases of dehydration wherefainting, unconsciousness, or any other severely inhibiting symptom is present (the patient is incapable of standing or thinking clearly), emergency attention is required. Fluids will be given through an IV, and within a few hours, the patient will return to normal unless a complication occurs.

Avoiding dehydration

A person's body loses, during an average day in atemperateclimate such as the United Kingdom, approximately 2.5litres of water. This can be through thelungs aswater vapor, through theskin assweat, or through the kidneys urine. Some (a less significant amount, in the absence ofdiarrhea) is also lost through thebowels.

During vigorous exercise or in a hot environment, it is easy to lose several times this amount. Heavy exercise in high temperatures could cause the loss of over 2.5 litres of fluid per hour, which exceeds the body's absorptive capacity.

Ethical concerns over death by dehydration

Judge Lynch of the Massachusetts Supreme Judicial Court argued that death by dehydration symptoms was "cruel and violent" in his opinion on the 1986 Brophy case:

  • The mouth would dry out and become caked or coated with thick material.
  • The lips would become parched and cracked.
  • The tongue would swell, and might crack.
  • The eyes would recede back into their orbits and the cheeks would become hollow.
  • The lining of the nose might crack and cause the nose to bleed.
  • The skin would hang loose on the body and become dry and scaly.
  • The urine would become highly concentrated, leading to burning of the bladder.
  • The lining of the stomach would dry out and the sufferer would experience dry heaves and vomiting.
  • The body temperature would become very high.
  • The brain cells would dry out, causing convulsions.
  • The respiratory tract would dry out, and the thick secretions that would result could plug the lungs and cause death.
  • At some point within five days to three weeks, the major organs, including the lungs, heart, and brain, would give out and the patient would die.

Be advised that death due to dehydration can occur in 3 days (or less in hot weather) and no one normally lives more than about 5-6 days without water.

External links

Look up Dehydration in Wiktionary, the free dictionary.

See also

Two people reflected in the water of a fish pond

Two people reflected in the water of a fish pond


updated: 25 March, 2019