Hi Jenny,
The most important thing to do to stop a bleed is to apply pressure, regardless of whether he has von Willebrand's disease or not. When a
wart is pulled out, the resulting wound is a little deeper than a normal skin scrape, which is why it is harder to stop the bleed without pressure. His condition has definitely made it harder for the own body's clotting ability to stop it on the surface.
What you need to do is apply firm direct pressure over the wound, or get him to do it, if he's old enough. Check after 10-15 minutes, and if it is still oozing even slightly, repeat the pressure again. Resist the urge to keep checking, because the constant pressure is needed to help the body form the clot at the wound. Use a piece of gauze if you can, but if you don't have it on hand, the band aid itself is fine. Try not to change the band aid unless it is completely soaked, which will be less likely if you put continuous pressure. Once it has stopped, resist the urge to clean the wound and don't touch any dried or clotted blood that is on the surface. Just cover it for now so that he doesn't scratch it again, and you can clean it the next day.
Surface bleeds on the skin are easier to stop than internal bleeds or bleeds at awkward places simply because they are at an area that we can compress. If you need the pressure for longer than 2-3 cycles, then you might want to consider using a compression bandage, which is basically gauze with a stretchy bandage that pushes the gauze to apply pressure on the wound. This is essentially the same as putting pressure but just frees him to do other activities while waiting for the bleeding to stop. You might want to get help for this, because it is important when wrapping up the area that you do not block circulation to the
limbs or other areas.
Hope this helps, and all the best to you and your son.
Regards,
Dr. Teh