How does one get OR training at my age? early 50s

I am a BSN graduate from 77 with my last clinical experience dating back 20 years. I have been in Case management for the last few years. I want to volunteer on a Mercy Ship in a year or so. Most of their needs are OR, ICU and Recovery. I have experience in all but OR. Any ideas how I can get back in the game easily...refresher programs (Where are they?)....hospital training?
thanks, Bel