CRNA subspecialty training/residency/fellowship possible and where

I want to first apologize for posting on a CRNA board (and haven't applied to school yet). I have a specific question that I feel no other forum is capable of answering. I hope this isn't a stupid question. I would like to know if it is possible to, after anesthesia school and becoming licensed, to reenter education (sort of like a fellowship) to specialize or gain more specific training in a certain area. In my situation, I am very interested in trauma. I know that this is part of the curiculum of nurse anesthesia school in many areas. I am just curious to know if it is possible to have type of residency/fellowship in a specialized area sort of like an anesthesiologist. If so, does anyone have any schools/hospitals doing this and a link, etc. Thank you!