Hypovolemia, also known as volume depletion or volume contraction, is a state of abnormally low extracellular fluid in the body. This may be due to either a loss of both salt and water or a decrease in blood volume. Hypovolemia refers to the loss of extracellular fluid and should not be confused with dehydration.Hypovolemia is caused by a variety of events, but these can be simplified into two categories: those that are associated with kidney function and those that are not. The signs and symptoms of hypovolemia worsen as the amount of fluid lost increases. Immediately or shortly after mild fluid loss (from blood donation, diarrhea, vomiting, bleeding from trauma, etc. ), one may experience headache, fatigue, weakness, dizziness, or thirst. Untreated hypovolemia or excessive and rapid losses of volume may lead to hypovolemic shock. Signs and symptoms of hypovolemic shock include increased heart rate, low blood pressure, pale or cold skin, and altered mental status. When these signs are seen, immediate action should be taken to restore the lost volume. Signs and symptoms
Signs and symptoms of hypovolemia progress with increased loss of fluid volume.Early symptoms of hypovolemia include headache, fatigue, weakness, thirst, and dizziness. The more severe signs and symptoms are often associated with hypovolemic shock. These include oliguria, cyanosis, abdominal and chest pain, hypotension, tachycardia, cold hands and feet, and progressively altering mental status.
Infusing colloid or crystalloid IV fluids also dilutes clotting factors in the blood, increasing the risk of bleeding. Current best practice allow permissive hypotension in patients with hypovolemic shock, both avoid overly diluting clotting factors and avoid artificially raising blood pressure to a point where it "blows off" clots that have formed. Hospital treatment
Fluid replacement is beneficial in hypovolemia of stage 2, and is necessary in stage 3 and 4. See also the discussion of shock and the importance of treating reversible shock while it can still be countered. The following interventions are carried out:

IV access
Oxygen as required
Fresh frozen plasma or blood transfusion
Surgical repair at sites of bleedingVasopressors (such as dopamine and noradrenaline) should generally be avoided, as they may result in further tissue ischemia and dont correct the primary problem. Fluids are the preferred choice of therapy. History
In cases where loss of blood volume is clearly attributable to bleeding (as opposed to, e.g., dehydration), most medical practitioners prefer the term exsanguination for its greater specificity and descriptiveness, with the effect that the latter term is now more common in the relevant context. See also
Hypervolemia
Non-pneumatic anti-shock garment
Polycythemia, an increase of the hematocrit level, with the "relative polycythemia" being a decrease in the volume of plasma
Volume status


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