obviously eventually if people keep on leaking blood their pressure will fall  but you could have a situation where there's not a single drop of blood yet lost to the system and yet the person's in shock because the blood's not being circulated properly off the heart, not a drop of blood lost to the system, but insufficient pressure, so shock can be caused by either of those two things, failure of the circulatory system because the pressure of the volume drops dangerously low, okay, you did a lot of work on what the person looks like, yes  you as the casu you as the first aider will see this person in front of you, what will they be like?