Many posts talk about Sole Survivor being useless in today's game, and that's true, but I did post a long while back a possible solution.

Sole Survivor, 90s CD, 15 second duration.
->Marks yourself with the Sole Survivor effect.
->Sole Survivor effect: Compiles all of received and dealt damage. When the effect expires, you heal and gain blood according to the compiled amount. Pressing the ability again ends the effect early.