from what ive read because both anavar and hdrol are methylated they put stress on the liver. Hdrol however, puts a lott more stress on it and it isnt recomended to run two compunds like that at the same time. I would def take some cycle support if you arent. If i were you, i would do the hdrol and then the var, but if i was old enough to run a real cycle (which im not yet) ide prolly run it with test and drop the var, unless you dont want any of the sides from the test, in that case var would be a better idea, except the gains wouldn't be as good.
here is a link to a very informative site on hdrol, it discusses this topic more in depth in here:
http://forums.steroid.com/showthread.php?t=422676