Clinical features of dehydration

Signs and symptoms of dehydration have poor sensitivity and specificity.

• factors with sensitivity >80% - dry mucous membranes in the mouth and nose and longitudinal furrows on the tongue.
• factors with specificity >80% - speech incoherence, extremity weakness, dry axilla and sunken eyes (1).

The clinical features of dehydration are caused by the water loss from the two compartments, for example:

• loss of tissue turgor results from depletion of the intracellular pool
• hypotension results from depletion of the extracellular pool

The clinical features of mild-to-moderate and severe dehydration are given below:

• mild-to-moderate
• dry, sticky mouth
• sleepiness or tiredness
• thirst
• decreased urine output
• few or no tears when crying
• muscle weakness
• headache
• dizziness or light-headedness
• severe dehydration
• extreme thirst
• extreme fussiness or sleepiness in infants and children; irritability and confusion in adults
• very dry mouth, skin and mucous membranes
• lack of sweating
• little or no urination—any urine that is produced will be dark yellow or amber
• sunken eyes
• shrivelled and dry skin that lacks elasticity and does not ‘bounce back’ when pinched into a fold
• low blood pressure
• tachycardia
• delirium or unconsciousness (1)

Reference:

• (1) Jéquier E, Constant F. Water as an essential nutrient: the physiological basis of hydration. Eur J Clin Nutr. 2010;64(2):115-23