Dehydration is the condition in which there is excessive loss of body fluids, mostly water. Fluid loss mostly exceeds the amount of fluids taken in. In dehydration, fluids are lost from blood, extracellular spaces and then intracellular spaces. Dehydration can be classified into hypertonic, isotonic or hypotonic (based on the type of fluid loss) and mild, moderate or severe (based on severity).
BASED ON TYPE OF FLUID LOST
Hypertonic (Hypernatremic) Dehydration: This occurs when more water than sodium is lost from the body. This result in a higher concentration of extracellular fluids than intracellular fluids making it hypertonic and hence draws more water from the cells. This causes cell shrinkage and may lead to brain shrinkage.
Possible causes include hyperventilation, end-stage renal failure, diarrhoea in children and water deprivation.
Isotonic (Isonatremic) Dehydration: This occurs when a proportionally the same quantity of sodium and water is lost from the body. Therefore, the concentration of extracellular fluids remains the same. About 80% of cases of dehydration can be attributed to isotonic dehydration.
Possible causes include severe bleeding, diarrhoea and repeated vomiting.
Hypotonic (Hyponatremic) Dehydration: This is caused by proportionally more sodium loss than water resulting in a lower concentration of extracellular fluids compared to the intracellular fluids. This leads to cell swelling and may cause cerebral oedema (brain swelling)
Possible causes include burns, heatstroke and accidental infusion of hypotonic fluids.
BASED ON SEVERITY
Mild Dehydration: This is when the body has lost about 2% of its total fluid
Moderate Dehydration: This is when the total fluid loss reaches 5%
Severe Dehydration: This is when the body reaches 10% fluid loss, considered an emergency
NURSING INTERVENTION FOR DEHYDRATION
- Monitor blood pressure
- Check vital signs, noting peripheral pulses.
- Strictly monitor intake and output. Observe the physical properties of the urine.
- Give correct and right amount of IV fluids.
- Provide frequent, oral care.
- Encourage small, frequent feedings.