Well, spring has sprung early but even here in NC we are going to get snow tonight and a freeze tomorrow. We had one freeze all last month and it killed the leaves off the hydrangeas. Will the branches put on more leaves or are they done for this year. I noticed a little green coming up from the base.
A freeze like that shouldn't kill the plant so it should come back. Give it some time to leaf out again, and then if there are some little branches that don't put out new leaves then you can trim those out. The real damage though would be the flower buds if this is one of the hydrangeas that blooms on old wood--if that's the type you have then you may not get flowers this year (or get less than usual). If it's one that blooms on new wood though you should still get flowers too.