<prompt> Severe hypovolemic shock occurs when blood volume less is -10203040  <response>: Hypovolemic shockHypovolemic shock is the most common form of shock.This is due to a decrease in blood volume either by the loss of blood or plasma.Grading of hypovolemic shockMild hypovolemia When volume loss is less than 20. There is generally mild tachycardia but relatively few external signs.Moderate hypovolemia When volume loss is between 20-40. Normal blood pressure is maintainedin the supine position, but there are postural hypotension and tachycardia on erect posture.Severe hypovolemia When volume loss is 40. The classical signs of shock appear i.e., marked tachycardia, hypotension, disorientation. 