Conversation so far:
when does meredith choose derek in season 3
Meredith makes a decision between Derek and Finn, telling Finn that he is a good man and probably a better man, but Derek is the one on episode 4.
which episode does Meredith makes a decision between Derek and Finn
Meredith makes a decision between Derek and Finn on episode 4 What I Am“
does meredith have a surgery in the episode What I Am“
Meredith's appendix bursts and she is admitted for surgery. Addison works with a pregnant woman who wants to give birth naturally, but needs to have a cesarean section.

Question: what happens to izzie
Self-contained rewrite: what happens to izzie on episode 4 What I Am“