i cant remember the name of what i used but it is the same size and shape (and made by the same company, i believe) as the pocket pharmacopaea (sorry, i suck at spelling) pocket book. i think it is titled critical care or something like that. it helped me tremendously while i did a MICU rotation as a 4th year. there is another thread that talks about what books to get as an intern that mentions an ICU reference book (not sure if it is pocket sized and thick or a full fledged textbook) that i have heard people recommend before.