I don't have the time nor the inclination to do a complete review for you. However, if you are willing to look you will see that many places will take your organs before you are completely dead. See the law in Israel, Wales, Austria, Germany, on and on. If they can pronounce you *dead* even though your organs are still functioning (and they have to be still functioning to be useful for transplanting) they can pronounce you ready to be dead by withholding water and food. Are you happy with that?
Citations?
Here in the Us. NIH
Presuming consent, presuming refusal: organ donation and communal structure. http://www.ncbi.nlm.nih.gov/pubmed/11186027
Wales First opt-out organ donation scheme in UK set to be approved in Wales Under new bill, adults would be assumed to have consented to use of organs and tissues unless they stipulate otherwise http://www.theguardian.com/society/2013/jun/30/opt-out-organ-donation-scheme-uk-wales
Austria The Austrian Hospitals Law allows individual organs or parts of organs to be removed from a deceased person for transplantation, in order to save the life www.bmeia.gv.at/en/embassy/...austria/organ-donation-in-austria.html
Well there you go you cite locations OUT SIDE of the US…. If you live in those countries then be sure and opt out. I on the other hand live in the US and my point still stands.