Unless you're starting this chart review from scratch, I'm sure there is an attending/resident you can ask about what questions are important to address with this review.
If you DID start this from scratch, why? Is it to see if there is a difference in rate of complications/morbidity/mortality? Length? Cost (huge thing that journals are looking for now are cost-analyses)?
Figure out what your hypothesis (or hypotheses) is, then go from there.
Er wait a second, just read your post again. Doing a meta analysis of various articles already published is NOT a chart review. A meta analysis is a pretty hard thing to put together, IMO. If you can get on a regular chart review instead it'll be a much easier use of your time.