First off, don't fret about "not being up to speed" because you are starting out in a different specialty. Tele/ICU can be very tough at times. I started out there and I learned A LOT.
I also agree with getting a good brain sheet. That is crucial. Get yourself a good stethoscope, too. A lot of nurses favor Littmanns, including myself. I personally have the Cardiology III which was expensive (I think around $150 or so) but definitely worth the investment. I have had it for 3 years and it still works great. I also have a Classic II S.E. that I have had for 5 years (that is the one I used in nursing school and then I decided to upgrade towards the end) and that also works great. I also bring a few black clicky pens (so you don't have to worry about the caps), a highlighter (I prefer to use that instead of a red pen), penlight, sharpie (in case I had to mark NG output or chest tube drainage output), scissors & tape. I also used a storage clipboard (it opens up so you can store things inside like papers, extra pens, etc). You can purchase them at Walmart for nearly $10.
I also like to use my iPhone. Some of my favorite apps:
* CriticalCare - I think it was $2.99 but this is a goldmine of information. The navigation could be better, though.
* ACLS Manual
* Heart Murmurs
* Lab Values+
* Micromedex (I love this even more than Lexicomp)
* ABG Stat
* !0 Second NIHSS Stroke Scale
And of course, Allnurses
Brush up on your cardiac rhythms. If you're not already ACLS certified, get yourself into an ACLS class if your employer provides them. Look up vasoactive medications and drips. The Manual of Critical Care Nursing
is an excellent resource.