You find a way, (to store your own blood), let us know
I thought it was a fairly common practice:
"When faced with major surgery, you may have concerns about the risks of blood transfusions. One way to make it safer is with a preoperative autologous donation (PAD), in which your blood is collected before surgery and given back to you during or after surgery if you should happen to need it."
https://www.verywellhealth.com/blood-donation-before-surgery-2549514#Surgery%20with%20High%20Blood%20Loss