I started out as a new grad in the CVICU, as well. We do OHS here, and I was oriented to fresh hearts about six months ago. I have been an RN for almost 2 years, now. Let me start out by saying welcome to the lifestyle, and you are perfectly capable of being a fantastic heart nurse. It's big and scary at first, but you will soon establish your own rhythm and routine and start feeling more comfortable.
Each hospital manages their patients slightly differently, but the main things I would be at least moderately familiar with would be electrolyte replacement, vasopressors, inotropes, and insulin drips (though those protocols vary widely facility to facility). If you are not already familiar with your facilities Swan/PA catheters, study them. Learn what filling pressures are desired and your cardiac surgeon's preferences. All of that will come with time and experience.
Relax, take a deep breath, and enjoy. You have just dove into a specialty that is as intriguing as it is complicated. Good luck with orientation!
Last edit by 1smartrn on Apr 25, '10