I am sorry MM. Having a son with bp, I can relate to your concern and fear that you won't make the best decisions for Miguel. My son currently takes abilify and prozac. This combination keeps him pretty stable; however, when an upsetting event happens in his life, he cannot move beyond it without lots of intervention from his t and from me. We are currently in one of these times because of a low grade he received.
I know that none of our cases of mood disorders are exactly alike, but I wonder how much the anticipation of Miguel's upcoming surgery if affecting his thoughts.
Good luck, and I hope that Miguel finds peace soon.
Bluemountains