Learning: Infant, Medela

Medela Pump Parts- Reuse Old Ones or Buy New?

Hi all- I am expecting my second child in about 6 weeks! I have a Medela Pump-in-Style breast pump that I used for my last child- totally loved it! I'm wondering about what parts I should replace... should I get new tubing, bottles, shields, etc, or can I simply sterilize all the old stuff I had from 2 years ago? C.