Try lightly rinsing the most of it out, then squirt some Simple Green on it and soak it good. Then go ahead and wash them. Simple Green has tackled ANY stain we have used it on, including Mustard. Go buy a bottle, it works !
To remove blood stains on clothing, you first need to put paper towels to absorb as much of the stain in case they are still fresh. Hold the clothing under running cold water, without squeezing it. This helps ensure that the blood does not set in the clothing. Get a large basin and fill it with cold water. Add enough detergent into it. Get additional details from http://www.ehow.com/how_4775936_blood-stains-out-of-clothes.html.
Wash/soak in warm soapy wather then rinse in cold... If it's old blood, and it will survive it (this is considered bad by most spot Nazis) I throw it in the washing machine and bleach it within an inch of its life.
Make sure you do a second rinse if you do that. It's not for the bleached clothes. It's to save your next load of laundry!