I'm an outlier here. Don't know how I'd actually respond in the situation, but philosophically I'm not comfortable with organ donor body parts or even blood transfusions. Don't even like the idea of vaccines and medicines that use human body tissue, preborn or not.
Yeah, I know my view is extreme.
Donors must be mentally competent, of legal age, and thoroughly informed of tissue or organ's destination and use; donations from a murder or suicide victim should be deemed unacceptable. There should be no coercive circumstances, e.g. "donations" from incarcerated people; there should be no payment of any kind (to donor or various marketers)--- other than actual break-even costs of handling, shipment, etc.--- to prevent commercial motivation; under no circumstances should there be donation of a vital organ (e.g. heart, brain) unless donor is already dead. And I mean "dead" dead. Irreversibly dead. Not just severely cognitively impaired. (The definition-of-death thing is complicated but important.)
And no proxy consent. If the donor did not consent in writing, no "donation" of the organs by the next of kin, no parental "consent" for organs of child (born or unborn) or anybody else but the donor, first-person and in advance.
Blood, freely donated, for transfusions, I am okay with. Organs become a gray area when one considers that the body must be kept 'alive' in order to do so, and the criteria for 'brain dead' shifted with Terry Schiavo, although the way she was murdered likely rendered her organs unsuitable for donation.
Will the criteria for being a donor be changed for convenience and profit? Most assuredly, if we allow our society to head down that road. Sooner or later the old "lifeboat problem' (or 'kidney machine problem'-- same thing) will come to prominence as some lives become considered to be 'more important' than others, and those criteria will be established by little more than the whim of those in power.
If we have the ability to clone organs from the stem cells of the intended recipient or even a close living match, then this should be the course taken. Rejection should be far less of a problem if the recipient's cells were cultured to make the organ.
Humanity treads on dangerous ground, teetering again on the precipice above the fiery abyss.