Watchtower's "sustaining life by means of blood" redefinition of the issue is unbiblical and ridiculous.
The bible does not say it is wrong to sustain your life by means of blood. It only says that blood is not to be eaten because blood is being used on the altar to atone for sin. (Leviticus 17:10-12). The idea that it is wrong to sustain your life by means of blood, was invented by Watchtower out of whole cloth.
It is also ridiculous to say that the bible is against using blood to sustain your life when blood was supposedly created for the very purpose of sustaining life! Also, every JW is sustaining their life by means of native blood flowing in their veins. So if it is wrong to sustain your life by means of blood then every JW should have to slit their throat and bleed themselves out so as to comply.
Watchtower is dishonestly and foolishly redefining the blood issue because if they go only by what is stated in the bible, the blood issue does not apply to transfusions.