Part-time on CCU

Hi All,
I recently changed my hours on a cardiac step-down until from full-time to pool. My experience has been 1 year on this floor since graduation last spring. Does anyone else work pool and how many hours do you feel is necessary to maintain your practice? Recently, when I have arrived for shifts, my confidence seems lessened. Also, are there any resources or books anyone uses to stay "brushed up" on knowledge/skills necessary in this setting? Thanks for all your input.