After a major blood loss, i.e. hemorrhagic shock, there will be a decrease in urine output, which is a pre-renal oliguria, because the blood supply to the kidneys is reduced and vasoconstriction occurs, so there will be a decrease in the volume of urine and concentration of urine. The patient will also have obvious coldness and sweating, and should be treated promptly with antishock therapy. If there is concomitant substantial organ damage, further surgery should be chosen, and if necessary, organ removal should be chosen. In the case of massive blood loss caused by trauma, capacity expansion should be carried out in a timely manner to supplement colloid and crystalloid fluids, and plasma and red blood cells should be supplemented intravenously if necessary to actively rescue shock, ensure blood supply and oxygen supply to tissue cells and organs, and prevent the occurrence of multiorgan failure and dysfunction. During the treatment period, attention should also be paid to the prevention of infection and the emergence of related complications.