Are you referring to Terri Schiavo? Well, many conservatives wrote here in FR that there was more than ample precedent for him to intervene on her behalf. They cited several cases, (which I do not have), dating from the 1800's to the late 20th century. Bubba Clinton used the feds to intervene in the Elian Gonzales case while that case was still winding its way through the Federal Appeals Courts, and though many did not like it, nobody made a legal challenge to his authority to do it. Bush could have stepped up and saved Terri's life and cited the Clinton-Elian action as precedent.
I firmly believe that if Bush had done something similar for Terri Schiavo it would have bolstered his popularity enormously, because it simply was the right thing to do. He had the force of the House, the Senate, the Christian Church leaders, and the majority of the American people behind him. At the very least he could have made his political speech about how "it is the duty of the strong to protect the weak" before they starved the poor girl to death, and then taken steps to put his money where his mouth was. As it were, he embarrassed himself with that statement by not acting on his own (alleged) beliefs.