The fundamental element in the treatment of hemorrhagic shock is the correction of the deficit of blood volume before critical changes have occurred which render the shock irreversible. In the dog which has been subjected to severe hemorrhagic shock the reinfusion of shed blood almost invariably leads to a recovery of blood pressure and cardiac output. This recovery is short-lived in animals which have passed the point of reversibility, and it is a matter of the greatest difficulty to explain why one animal will go on to survive while another will die.
During the period of hypotension the perfusion of tissues and the consumption of oxygen are both greatly reduced. The degree of depression of oxygen consumption during shock has been shown by Guyton and Crowell to bear a relationship to recovery.11 Immediately after reinfusion the oxygen consumption rises along with the blood pressure and cardiac output, but it