What is the stance of Islam on blood transfusion? Can a Muslim receive blood from a non-Muslim who might not have been living a Muslim life, e.g. eating pork?
It is allowed to donate blood in islam, as long as it does not put life of other in any harm, and it should be take into consideration that should only go for it,when there is no other alternative left.
As proved from this verse of Quran:
"He has explained to you in detail what is forbidden to you, except under compulsion of necessity…” [al-An’aam 6:119]
Regarding permissibiloity of taking non-muslim blood, then it is only allowed when there is no muslim present to give blood, or as a last resort
Further details here: http://islamqa.info/en/2320