I've got the company booklet for Neo-PICC here, and it doesn't specify what to use when cleaning (it specifically says:
Clean the insertion site with prep solution(s) per policy, starting at the insertion site and working outward, in concentric circles, to an area as big as the transparent dressing. Allow to dry completely. Note: In the neonatal setting, sterile water is sometimes used to remove the prep solution at this point, to prevent direct uptake into the venous system.)
*Source: Cheryl A. Klein, RN, Manager of Clinical Education
Klein-Baker Medical, Inc.
Maybe you could email her and get one of these little books? It has everything you need to know about this particular brand of PICC lines and has been very helpful to me.
In our facility, we use Betadine first, allowing it to totally dry, and then alchohol or sterile water pads to remove it (don't leave the Betadine on the skin of a neonate, especially under a dressing).
According to the booklet, you use tape to secure the line (these particular lines have "hearts" that are stronger than the catheter itself, and this is what you're taping over; I don't know what brand they used for your baby) and then a transparent dressing. We don't use gauze- this necessitates a change q 48hrs. Don't put tape directly on the catheter- they're very weak and easily torn or dislodged. Don't reinsert the catheter if it has come out of place, call the MD.
A good bet, as mentioned above, would be to call the hospital the baby came from and have them fax over a copy of their policy for PICC changes. I'm sure they'd be willing to do that.