I'm no nurse but I am waist deep in nursing school. I personally think it is too big of a subject to study up on before school, but I'm no expert on this. I would say that knowing some normal lab values would come in handy early on. Maybe know the norms for electrolytes, BUN's, and blood work for example. They are found in every NCLEX study guide. I say this because I missed a few questions on my first test because I did not understand the scenario that was presented to me. I didn't know if he had too many platelets or too few, too much Na or not enough, too many WBC's or too low, etc. Just my 2 cents.