one rout you may consider is family nurse practitioner, as you probably know it will allow you to work with all age groups. regarding the transition into the er, most er take fnp's. also what is your background as a rn , if you have icu, er, ccu, flight you should be able to transition without too much trouble. my background is neuro, peds, icu, er, and flight before going to grad school, i work occ / employee full health time in an industrial plant but still work a few days a month in the er. being a fnp will allow you to work anywhere but some times np's run into problems finding a job if the are an acute care, or peds-np because of the age or because of how the job description is worded. good luck