Don,
You can' t assume too much when trailing an animal. You' ll wind up frustrated and likely walking past him following assumptions........you need a plan of attack.
I' m with c903, why can' t you blood trail? If there was a pool of blood where you hit him along with the broken arrow, there has to be more blood. It doesn' t wash away that fast.....tree canopy higher leaves etc can and will protect blood sign to a degree. don' t ignore the possibility of a traditional blood trail.
(When you say you found a pool of blood........was it where you shot or was it at a point where the deer traveled to AFTER the shot?)
Just because you THINK he' s heading somewhere because of a direction of travel don' t just blindly go there first......try to FOLLOW him to his final destination.
Look for scuffs in the dirt, a panicked animal leaves sign, you need to make yourself at least TRY to see it.
Is there any other detail you can provide? I am actually a little confused as to what really happened based upon your story.