It's been a while since I've taken any certification exam (CSC last taken 2012) and am excited to have passed the CEN exam today. 117/150 correct answers. Especially since I did not really do much studying for cardio and pulmonary but really put more focus on areas that I'm not too adept with.
I used the Sheeys Manual of Emergency care, just read it front to back, watched all of Mark Boswell videos on YouTube, videos by Osmosis on YouTube and a few other videos from various authors here and there on YouTube.
I printed out the blueprint and just studied every thing there. I didn't put any emphasis on cardio or pulmonary (being a CVICU RN for a long time) except when answering test questions.
Time spent studying was a little over 2 months.
WOOT!! Congrats on passing CEN again.