If Cole chooses to save the doctors, we get a cutscene of Trish’s death, and she will die either loving or hating Cole (depending on his good/evil points), but she will die all the same. And if you choose to save Trish, a female doctor is one of those that dies, and she will die either loving or hating Cole (depending on his good/evil points), but she will die all the same, just like Trish in the “save the doctors” choice. Who is that doctor?
According to the wiki entry, if you choose to save Trish, the "doctor" who dies is Trish, switched for one of the doctors, who turns out to be the one you saved.
Kessler tells Cole that Trish has been kidnapped, and that Cole has to make a choice. One roof holds Trish, another roof holds six doctors. The doctors could save countless lives, while Trish is what Cole cherishes the most.
Good: Thinking for the greater good, Cole rescues the doctors.
Evil: Thinking only of himself, Cole attempts to rescue Trish. What Cole doesn't know is that Kessler actually disguised her as one of the six doctors.
Either way, Trish dies. If Cole's Karma is good, Trish tells him how proud she was that he was using his powers for good, and that she loves him, before falling to her death. If Cole's Karma is evil, Trish tells him how much she hates him, saying that "God gave you these powers, and you squandered them." She then falls to her death.