It would be good to find an article or info from the manufacturers of hemoglobin-based products where they state it is made from expired human blood or animal blood. Most jws are not aware of that.
Hemopure
Polyheme
http://www.jehovahs-witness.net/watchtower/medical/125938/1/Hemopure-cows-blood#.U4heJblOVLM
http://www.phlbi.org/divisions/blood-disorders/artificial-blood/
Plus the WTS says that blood should be poured out. Try and find a recent reference to that in the WTS pubs.
(Deuteronomy 12:26, 27) . . .. 27 And you must render up your burnt offerings, the flesh and the blood, upon the altar of Jehovah your God; and the blood of your sacrifices should be poured out against the altar of Jehovah your God, but the flesh you may eat.
*** w00 10/15 pp. 30-31 Questions From Readers ***
Occasionally, a doctor will urge a patient to deposit his own blood weeks before surgery (preoperative autologous blood donation, or PAD) so that if the need arises, he could transfuse the patient with his own stored blood. However, such collecting, storing, and transfusing of blood directly contradicts what is said in Leviticus and Deuteronomy. Blood is not to be stored; it is to be poured out—returned to God, as it were. Granted, the Mosaic Law is not in force now. Nevertheless, Jehovah’s Witnesses respect the principles God included in it, and they are determined to ‘abstain from blood.’ Hence, we do not donate blood, nor do we store for transfusion our blood that should be ‘poured out.’ That practice conflicts with God’s law.