Honestly the best peds anesthesia Q-bank that exists is the True Learn Advanced Q bank and sort for only "pediatric" category questions. Unfortunately they don't sell Qbank categories a-la-cart, so you'd be way overpaying.
The one linked above ("Comprehensive board review") is probably the best option, but it's not very good compared to TrueLearn. We used it during my fellowship for our weekly board review sessions... there's a lot of good questions mixed with some really bad questions. Probably every third of fourth question would elicit a comment from one of our faculty of "This is a terrible question. I completely disagree with their answer and explanation." So take that for what it's worth.
Another review book I like is called "Condensed review of pediatric anesthesia". It was a good one to read through during the year, nice balance of covering the material well but not being overly detailed. Unfortunately, it's not a question bank, just a series of short primers.
It's a tough exam to study for, at least to do a dedicated study for. This probably isn't a helpful statement, but the best preparation is to perform well as a resident on ITE's, pass the advanced, and then complete a demanding fellowship with a lot of exposure and reading throughout the year of any of the major peds anesthesia textbooks (Cote is my favorite).
